Merge pull request #3525 from fjl/all-gosimple-cleanup

all: clean up lint issues, remove more dead code

118 files changed, 444 insertions, 1976 deletions

diff --git a/accounts/abi/abi_test.go b/accounts/abi/abi_test.go
index b1bfcb012..1e5ee0efe 100644
--- a/accounts/abi/abi_test.go
+++ b/accounts/abi/abi_test.go
@@ -67,10 +67,10 @@ func TestTypeCheck(t *testing.T) {
 		{"uint16[3]", [4]uint16{1, 2, 3}, "abi: cannot use [4]uint16 as type [3]uint16 as argument"},
 		{"uint16[3]", []uint16{1, 2, 3}, ""},
 		{"uint16[3]", []uint16{1, 2, 3, 4}, "abi: cannot use [4]uint16 as type [3]uint16 as argument"},
-		{"address[]", []common.Address{common.Address{1}}, ""},
-		{"address[1]", []common.Address{common.Address{1}}, ""},
-		{"address[1]", [1]common.Address{common.Address{1}}, ""},
-		{"address[2]", [1]common.Address{common.Address{1}}, "abi: cannot use [1]array as type [2]array as argument"},
+		{"address[]", []common.Address{{1}}, ""},
+		{"address[1]", []common.Address{{1}}, ""},
+		{"address[1]", [1]common.Address{{1}}, ""},
+		{"address[2]", [1]common.Address{{1}}, "abi: cannot use [1]array as type [2]array as argument"},
 		{"bytes32", [32]byte{}, ""},
 		{"bytes32", [33]byte{}, "abi: cannot use [33]uint8 as type [32]uint8 as argument"},
 		{"bytes32", common.Hash{1}, ""},
@@ -80,7 +80,7 @@ func TestTypeCheck(t *testing.T) {
 		{"bytes", [2]byte{0, 1}, ""},
 		{"bytes", common.Hash{1}, ""},
 		{"string", "hello world", ""},
-		{"bytes32[]", [][32]byte{[32]byte{}}, ""},
+		{"bytes32[]", [][32]byte{{}}, ""},
 		{"function", [24]byte{}, ""},
 	} {
 		typ, err := NewType(test.typ)
@@ -343,8 +343,8 @@ func TestPack(t *testing.T) {
 		{"uint16[]", []uint16{1, 2}, formatSliceOutput([]byte{1}, []byte{2})},
 		{"bytes20", [20]byte{1}, pad([]byte{1}, 32, false)},
 		{"uint256[]", []*big.Int{big.NewInt(1), big.NewInt(2)}, formatSliceOutput([]byte{1}, []byte{2})},
-		{"address[]", []common.Address{common.Address{1}, common.Address{2}}, formatSliceOutput(pad([]byte{1}, 20, false), pad([]byte{2}, 20, false))},
-		{"bytes32[]", []common.Hash{common.Hash{1}, common.Hash{2}}, formatSliceOutput(pad([]byte{1}, 32, false), pad([]byte{2}, 32, false))},
+		{"address[]", []common.Address{{1}, {2}}, formatSliceOutput(pad([]byte{1}, 20, false), pad([]byte{2}, 20, false))},
+		{"bytes32[]", []common.Hash{{1}, {2}}, formatSliceOutput(pad([]byte{1}, 32, false), pad([]byte{2}, 32, false))},
 		{"function", [24]byte{1}, pad([]byte{1}, 32, false)},
 	} {
 		typ, err := NewType(test.typ)
@@ -458,12 +458,12 @@ func TestReader(t *testing.T) {
 	Uint256, _ := NewType("uint256")
 	exp := ABI{
 		Methods: map[string]Method{
-			"balance": Method{
+			"balance": {
 				"balance", true, nil, nil,
 			},
-			"send": Method{
+			"send": {
 				"send", false, []Argument{
-					Argument{"amount", Uint256, false},
+					{"amount", Uint256, false},
 				}, nil,
 			},
 		},
@@ -562,7 +562,7 @@ func TestTestSlice(t *testing.T) {
 
 func TestMethodSignature(t *testing.T) {
 	String, _ := NewType("string")
-	m := Method{"foo", false, []Argument{Argument{"bar", String, false}, Argument{"baz", String, false}}, nil}
+	m := Method{"foo", false, []Argument{{"bar", String, false}, {"baz", String, false}}, nil}
 	exp := "foo(string,string)"
 	if m.Sig() != exp {
 		t.Error("signature mismatch", exp, "!=", m.Sig())
@@ -574,7 +574,7 @@ func TestMethodSignature(t *testing.T) {
 	}
 
 	uintt, _ := NewType("uint")
-	m = Method{"foo", false, []Argument{Argument{"bar", uintt, false}}, nil}
+	m = Method{"foo", false, []Argument{{"bar", uintt, false}}, nil}
 	exp = "foo(uint256)"
 	if m.Sig() != exp {
 		t.Error("signature mismatch", exp, "!=", m.Sig())
@@ -779,8 +779,8 @@ func TestBareEvents(t *testing.T) {
 		"balance": {false, nil},
 		"anon":    {true, nil},
 		"args": {false, []Argument{
-			Argument{Name: "arg0", Type: arg0, Indexed: false},
-			Argument{Name: "arg1", Type: arg1, Indexed: true},
+			{Name: "arg0", Type: arg0, Indexed: false},
+			{Name: "arg1", Type: arg1, Indexed: true},
 		}},
 	}
 
diff --git a/accounts/abi/bind/bind.go b/accounts/abi/bind/bind.go
index 84cf22e3c..73e95e02a 100644
--- a/accounts/abi/bind/bind.go
+++ b/accounts/abi/bind/bind.go
@@ -147,21 +147,21 @@ func bindTypeGo(kind abi.Type) string {
 
 	switch {
 	case strings.HasPrefix(stringKind, "address"):
-		parts := regexp.MustCompile("address(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`address(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 2 {
 			return stringKind
 		}
 		return fmt.Sprintf("%scommon.Address", parts[1])
 
 	case strings.HasPrefix(stringKind, "bytes"):
-		parts := regexp.MustCompile("bytes([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`bytes([0-9]*)(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 3 {
 			return stringKind
 		}
 		return fmt.Sprintf("%s[%s]byte", parts[2], parts[1])
 
 	case strings.HasPrefix(stringKind, "int") || strings.HasPrefix(stringKind, "uint"):
-		parts := regexp.MustCompile("(u)?int([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`(u)?int([0-9]*)(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 4 {
 			return stringKind
 		}
@@ -172,7 +172,7 @@ func bindTypeGo(kind abi.Type) string {
 		return fmt.Sprintf("%s*big.Int", parts[3])
 
 	case strings.HasPrefix(stringKind, "bool") || strings.HasPrefix(stringKind, "string"):
-		parts := regexp.MustCompile("([a-z]+)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`([a-z]+)(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 3 {
 			return stringKind
 		}
@@ -191,7 +191,7 @@ func bindTypeJava(kind abi.Type) string {
 
 	switch {
 	case strings.HasPrefix(stringKind, "address"):
-		parts := regexp.MustCompile("address(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`address(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 2 {
 			return stringKind
 		}
@@ -201,7 +201,7 @@ func bindTypeJava(kind abi.Type) string {
 		return fmt.Sprintf("Addresses")
 
 	case strings.HasPrefix(stringKind, "bytes"):
-		parts := regexp.MustCompile("bytes([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`bytes([0-9]*)(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 3 {
 			return stringKind
 		}
@@ -211,7 +211,7 @@ func bindTypeJava(kind abi.Type) string {
 		return "byte[]"
 
 	case strings.HasPrefix(stringKind, "int") || strings.HasPrefix(stringKind, "uint"):
-		parts := regexp.MustCompile("(u)?int([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`(u)?int([0-9]*)(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 4 {
 			return stringKind
 		}
@@ -230,7 +230,7 @@ func bindTypeJava(kind abi.Type) string {
 		return fmt.Sprintf("BigInts")
 
 	case strings.HasPrefix(stringKind, "bool"):
-		parts := regexp.MustCompile("bool(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`bool(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 2 {
 			return stringKind
 		}
@@ -240,7 +240,7 @@ func bindTypeJava(kind abi.Type) string {
 		return fmt.Sprintf("bool[]")
 
 	case strings.HasPrefix(stringKind, "string"):
-		parts := regexp.MustCompile("string(\\[[0-9]*\\])?").FindStringSubmatch(stringKind)
+		parts := regexp.MustCompile(`string(\[[0-9]*\])?`).FindStringSubmatch(stringKind)
 		if len(parts) != 2 {
 			return stringKind
 		}
@@ -278,7 +278,7 @@ func namedTypeJava(javaKind string, solKind abi.Type) string {
 	case "bool[]":
 		return "Bools"
 	case "BigInt":
-		parts := regexp.MustCompile("(u)?int([0-9]*)(\\[[0-9]*\\])?").FindStringSubmatch(solKind.String())
+		parts := regexp.MustCompile(`(u)?int([0-9]*)(\[[0-9]*\])?`).FindStringSubmatch(solKind.String())
 		if len(parts) != 4 {
 			return javaKind
 		}
diff --git a/accounts/abi/type.go b/accounts/abi/type.go
index 7af7ff386..2bd341bd2 100644
--- a/accounts/abi/type.go
+++ b/accounts/abi/type.go
@@ -65,7 +65,7 @@ var (
 	//      string     int       uint       fixed
 	//      string32   int8      uint8      uint[]
 	//      address    int256    uint256    fixed128x128[2]
-	fullTypeRegex = regexp.MustCompile("([a-zA-Z0-9]+)(\\[([0-9]*)\\])?")
+	fullTypeRegex = regexp.MustCompile(`([a-zA-Z0-9]+)(\[([0-9]*)\])?`)
 	// typeRegex parses the abi sub types
 	typeRegex = regexp.MustCompile("([a-zA-Z]+)(([0-9]+)(x([0-9]+))?)?")
 )
diff --git a/build/ci.go b/build/ci.go
index 593fcd151..d530c24ca 100644
--- a/build/ci.go
+++ b/build/ci.go
@@ -195,7 +195,7 @@ func doInstall(cmdline []string) {
 			if err != nil {
 				log.Fatal(err)
 			}
-			for name, _ := range pkgs {
+			for name := range pkgs {
 				if name == "main" {
 					gobuild := goToolArch(*arch, "build", buildFlags(env)...)
 					gobuild.Args = append(gobuild.Args, "-v")
diff --git a/cmd/ethtest/main.go b/cmd/ethtest/main.go
index 7ce663dc0..14b839579 100644
--- a/cmd/ethtest/main.go
+++ b/cmd/ethtest/main.go
@@ -88,12 +88,7 @@ func runTestWithReader(test string, r io.Reader) error {
 	default:
 		err = fmt.Errorf("Invalid test type specified: %v", test)
 	}
-
-	if err != nil {
-		return err
-	}
-
-	return nil
+	return err
 }
 
 func getFiles(path string) ([]string, error) {
diff --git a/cmd/geth/accountcmd_test.go b/cmd/geth/accountcmd_test.go
index b6abde6d8..113df983e 100644
--- a/cmd/geth/accountcmd_test.go
+++ b/cmd/geth/accountcmd_test.go
@@ -148,7 +148,7 @@ Passphrase: {{.InputLine "foobar"}}
 		"Unlocked account f466859ead1932d743d622cb74fc058882e8648a",
 	}
 	for _, m := range wantMessages {
-		if strings.Index(geth.stderrText(), m) == -1 {
+		if !strings.Contains(geth.stderrText(), m) {
 			t.Errorf("stderr text does not contain %q", m)
 		}
 	}
@@ -193,7 +193,7 @@ Passphrase: {{.InputLine "foobar"}}
 		"Unlocked account 289d485d9771714cce91d3393d764e1311907acc",
 	}
 	for _, m := range wantMessages {
-		if strings.Index(geth.stderrText(), m) == -1 {
+		if !strings.Contains(geth.stderrText(), m) {
 			t.Errorf("stderr text does not contain %q", m)
 		}
 	}
@@ -212,7 +212,7 @@ func TestUnlockFlagPasswordFile(t *testing.T) {
 		"Unlocked account 289d485d9771714cce91d3393d764e1311907acc",
 	}
 	for _, m := range wantMessages {
-		if strings.Index(geth.stderrText(), m) == -1 {
+		if !strings.Contains(geth.stderrText(), m) {
 			t.Errorf("stderr text does not contain %q", m)
 		}
 	}
@@ -260,7 +260,7 @@ In order to avoid this warning, you need to remove the following duplicate key f
 		"Unlocked account f466859ead1932d743d622cb74fc058882e8648a",
 	}
 	for _, m := range wantMessages {
-		if strings.Index(geth.stderrText(), m) == -1 {
+		if !strings.Contains(geth.stderrText(), m) {
 			t.Errorf("stderr text does not contain %q", m)
 		}
 	}
diff --git a/cmd/geth/main.go b/cmd/geth/main.go
index 332e1ae8d..766e49f49 100644
--- a/cmd/geth/main.go
+++ b/cmd/geth/main.go
@@ -168,7 +168,6 @@ func init() {
 	}
 
 	app.After = func(ctx *cli.Context) error {
-		logger.Flush()
 		debug.Exit()
 		console.Stdin.Close() // Resets terminal mode.
 		return nil
diff --git a/cmd/swarm/main.go b/cmd/swarm/main.go
index 954ad3b13..71f53082a 100644
--- a/cmd/swarm/main.go
+++ b/cmd/swarm/main.go
@@ -129,7 +129,7 @@ func init() {
 	app.HideVersion = true // we have a command to print the version
 	app.Copyright = "Copyright 2013-2016 The go-ethereum Authors"
 	app.Commands = []cli.Command{
-		cli.Command{
+		{
 			Action:    version,
 			Name:      "version",
 			Usage:     "Print version numbers",
@@ -138,7 +138,7 @@ func init() {
 The output of this command is supposed to be machine-readable.
 `,
 		},
-		cli.Command{
+		{
 			Action:    upload,
 			Name:      "up",
 			Usage:     "upload a file or directory to swarm using the HTTP API",
@@ -147,7 +147,7 @@ The output of this command is supposed to be machine-readable.
 "upload a file or directory to swarm using the HTTP API and prints the root hash",
 `,
 		},
-		cli.Command{
+		{
 			Action:    hash,
 			Name:      "hash",
 			Usage:     "print the swarm hash of a file or directory",
diff --git a/cmd/utils/cmd.go b/cmd/utils/cmd.go
index a56507e4d..8666f3775 100644
--- a/cmd/utils/cmd.go
+++ b/cmd/utils/cmd.go
@@ -67,7 +67,6 @@ func Fatalf(format string, args ...interface{}) {
 		}
 	}
 	fmt.Fprintf(w, "Fatal: "+format+"\n", args...)
-	logger.Flush()
 	os.Exit(1)
 }
 
@@ -95,7 +94,7 @@ func StartNode(stack *node.Node) {
 
 func FormatTransactionData(data string) []byte {
 	d := common.StringToByteFunc(data, func(s string) (ret []byte) {
-		slice := regexp.MustCompile("\\n|\\s").Split(s, 1000000000)
+		slice := regexp.MustCompile(`\n|\s`).Split(s, 1000000000)
 		for _, dataItem := range slice {
 			d := common.FormatData(dataItem)
 			ret = append(ret, d...)
diff --git a/common/big_test.go b/common/big_test.go
index 1eb0c0c1f..4d04a8db3 100644
--- a/common/big_test.go
+++ b/common/big_test.go
@@ -27,7 +27,7 @@ func TestMisc(t *testing.T) {
 	c := []byte{1, 2, 3, 4}
 	z := BitTest(a, 1)
 
-	if z != true {
+	if !z {
 		t.Error("Expected true got", z)
 	}
 
@@ -79,11 +79,11 @@ func TestBigCopy(t *testing.T) {
 	z := BigToBytes(c, 16)
 	zbytes := []byte{232, 212, 165, 16, 0}
 
-	if bytes.Compare(y, ybytes) != 0 {
+	if !bytes.Equal(y, ybytes) {
 		t.Error("Got", ybytes)
 	}
 
-	if bytes.Compare(z, zbytes) != 0 {
+	if !bytes.Equal(z, zbytes) {
 		t.Error("Got", zbytes)
 	}
 }
diff --git a/common/bytes.go b/common/bytes.go
index b9fb3b2da..cbceea8b5 100644
--- a/common/bytes.go
+++ b/common/bytes.go
@@ -143,7 +143,7 @@ func Hex2BytesFixed(str string, flen int) []byte {
 		return h
 	} else {
 		if len(h) > flen {
-			return h[len(h)-flen : len(h)]
+			return h[len(h)-flen:]
 		} else {
 			hh := make([]byte, flen)
 			copy(hh[flen-len(h):flen], h[:])
diff --git a/common/bytes_test.go b/common/bytes_test.go
index 2e5208477..98d402c48 100644
--- a/common/bytes_test.go
+++ b/common/bytes_test.go
@@ -181,7 +181,7 @@ func TestFromHex(t *testing.T) {
 	input := "0x01"
 	expected := []byte{1}
 	result := FromHex(input)
-	if bytes.Compare(expected, result) != 0 {
+	if !bytes.Equal(expected, result) {
 		t.Errorf("Expected % x got % x", expected, result)
 	}
 }
@@ -190,7 +190,7 @@ func TestFromHexOddLength(t *testing.T) {
 	input := "0x1"
 	expected := []byte{1}
 	result := FromHex(input)
-	if bytes.Compare(expected, result) != 0 {
+	if !bytes.Equal(expected, result) {
 		t.Errorf("Expected % x got % x", expected, result)
 	}
 }
diff --git a/common/compiler/solidity.go b/common/compiler/solidity.go
index b0ca9bd75..d27bddd9f 100644
--- a/common/compiler/solidity.go
+++ b/common/compiler/solidity.go
@@ -32,7 +32,7 @@ import (
 )
 
 var (
-	versionRegexp = regexp.MustCompile("[0-9]+\\.[0-9]+\\.[0-9]+")
+	versionRegexp = regexp.MustCompile(`[0-9]+\.[0-9]+\.[0-9]+`)
 	solcParams    = []string{
 		"--combined-json", "bin,abi,userdoc,devdoc",
 		"--add-std",  // include standard lib contracts
diff --git a/common/format.go b/common/format.go
index 119637d2e..fccc29962 100644
--- a/common/format.go
+++ b/common/format.go
@@ -27,7 +27,7 @@ import (
 // the unnecessary precision off from the formatted textual representation.
 type PrettyDuration time.Duration
 
-var prettyDurationRe = regexp.MustCompile("\\.[0-9]+")
+var prettyDurationRe = regexp.MustCompile(`\.[0-9]+`)
 
 // String implements the Stringer interface, allowing pretty printing of duration
 // values rounded to three decimals.
diff --git a/common/math/dist_test.go b/common/math/dist_test.go
index 826faea8b..f5857b6f8 100644
--- a/common/math/dist_test.go
+++ b/common/math/dist_test.go
@@ -41,24 +41,24 @@ func TestSum(t *testing.T) {
 
 func TestDist(t *testing.T) {
 	var vectors = []Vector{
-		Vector{big.NewInt(1000), big.NewInt(1234)},
-		Vector{big.NewInt(500), big.NewInt(10023)},
-		Vector{big.NewInt(1034), big.NewInt(1987)},
-		Vector{big.NewInt(1034), big.NewInt(1987)},
-		Vector{big.NewInt(8983), big.NewInt(1977)},
-		Vector{big.NewInt(98382), big.NewInt(1887)},
-		Vector{big.NewInt(12398), big.NewInt(1287)},
-		Vector{big.NewInt(12398), big.NewInt(1487)},
-		Vector{big.NewInt(12398), big.NewInt(1987)},
-		Vector{big.NewInt(12398), big.NewInt(128)},
-		Vector{big.NewInt(12398), big.NewInt(1987)},
-		Vector{big.NewInt(1398), big.NewInt(187)},
-		Vector{big.NewInt(12328), big.NewInt(1927)},
-		Vector{big.NewInt(12398), big.NewInt(1987)},
-		Vector{big.NewInt(22398), big.NewInt(1287)},
-		Vector{big.NewInt(1370), big.NewInt(1981)},
-		Vector{big.NewInt(12398), big.NewInt(1957)},
-		Vector{big.NewInt(42198), big.NewInt(1987)},
+		{big.NewInt(1000), big.NewInt(1234)},
+		{big.NewInt(500), big.NewInt(10023)},
+		{big.NewInt(1034), big.NewInt(1987)},
+		{big.NewInt(1034), big.NewInt(1987)},
+		{big.NewInt(8983), big.NewInt(1977)},
+		{big.NewInt(98382), big.NewInt(1887)},
+		{big.NewInt(12398), big.NewInt(1287)},
+		{big.NewInt(12398), big.NewInt(1487)},
+		{big.NewInt(12398), big.NewInt(1987)},
+		{big.NewInt(12398), big.NewInt(128)},
+		{big.NewInt(12398), big.NewInt(1987)},
+		{big.NewInt(1398), big.NewInt(187)},
+		{big.NewInt(12328), big.NewInt(1927)},
+		{big.NewInt(12398), big.NewInt(1987)},
+		{big.NewInt(22398), big.NewInt(1287)},
+		{big.NewInt(1370), big.NewInt(1981)},
+		{big.NewInt(12398), big.NewInt(1957)},
+		{big.NewInt(42198), big.NewInt(1987)},
 	}
 
 	VectorsBy(GasSort).Sort(vectors)
diff --git a/compression/rle/read_write.go b/compression/rle/read_write.go
index 03dffd607..0e7ad90ae 100644
--- a/compression/rle/read_write.go
+++ b/compression/rle/read_write.go
@@ -76,9 +76,9 @@ func compressChunk(dat []byte) (ret []byte, n int) {
 		}
 		return []byte{token, byte(j + 2)}, j
 	case len(dat) >= 32:
-		if dat[0] == empty[0] && bytes.Compare(dat[:32], empty) == 0 {
+		if dat[0] == empty[0] && bytes.Equal(dat[:32], empty) {
 			return []byte{token, emptyShaToken}, 32
-		} else if dat[0] == emptyList[0] && bytes.Compare(dat[:32], emptyList) == 0 {
+		} else if dat[0] == emptyList[0] && bytes.Equal(dat[:32], emptyList) {
 			return []byte{token, emptyListShaToken}, 32
 		}
 		fallthrough
diff --git a/console/console.go b/console/console.go
index 6e3d7e43c..8865f5e89 100644
--- a/console/console.go
+++ b/console/console.go
@@ -36,9 +36,9 @@ import (
 )
 
 var (
-	passwordRegexp = regexp.MustCompile("personal.[nus]")
-	onlyWhitespace = regexp.MustCompile("^\\s*$")
-	exit           = regexp.MustCompile("^\\s*exit\\s*;*\\s*$")
+	passwordRegexp = regexp.MustCompile(`personal.[nus]`)
+	onlyWhitespace = regexp.MustCompile(`^\s*$`)
+	exit           = regexp.MustCompile(`^\s*exit\s*;*\s*$`)
 )
 
 // HistoryFile is the file within the data directory to store input scrollback.
@@ -275,10 +275,7 @@ func (c *Console) Evaluate(statement string) error {
 			fmt.Fprintf(c.printer, "[native] error: %v\n", r)
 		}
 	}()
-	if err := c.jsre.Evaluate(statement, c.printer); err != nil {
-		return err
-	}
-	return nil
+	return c.jsre.Evaluate(statement, c.printer)
 }
 
 // Interactive starts an interactive user session, where input is propted from
diff --git a/core/block_validator_test.go b/core/block_validator_test.go
index 054686612..413c3cc8e 100644
--- a/core/block_validator_test.go
+++ b/core/block_validator_test.go
@@ -27,7 +27,6 @@ import (
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/params"
-	"github.com/ethereum/go-ethereum/pow/ezp"
 )
 
 func testChainConfig() *params.ChainConfig {
@@ -48,20 +47,19 @@ func proc() (Validator, *BlockChain) {
 }
 
 func TestNumber(t *testing.T) {
-	pow := ezp.New()
 	_, chain := proc()
 
 	statedb, _ := state.New(chain.Genesis().Root(), chain.chainDb)
 	cfg := testChainConfig()
 	header := makeHeader(cfg, chain.Genesis(), statedb)
 	header.Number = big.NewInt(3)
-	err := ValidateHeader(cfg, pow, header, chain.Genesis().Header(), false, false)
+	err := ValidateHeader(cfg, FakePow{}, header, chain.Genesis().Header(), false, false)
 	if err != BlockNumberErr {
 		t.Errorf("expected block number error, got %q", err)
 	}
 
 	header = makeHeader(cfg, chain.Genesis(), statedb)
-	err = ValidateHeader(cfg, pow, header, chain.Genesis().Header(), false, false)
+	err = ValidateHeader(cfg, FakePow{}, header, chain.Genesis().Header(), false, false)
 	if err == BlockNumberErr {
 		t.Errorf("didn't expect block number error")
 	}
diff --git a/core/blockchain.go b/core/blockchain.go
index 2081457a9..c3530b93c 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -46,9 +46,6 @@ import (
 )
 
 var (
-	chainlogger = logger.NewLogger("CHAIN")
-	jsonlogger  = logger.NewJsonLogger()
-
 	blockInsertTimer = metrics.NewTimer("chain/inserts")
 
 	ErrNoGenesis = errors.New("Genesis not found in chain")
@@ -150,7 +147,7 @@ func NewBlockChain(chainDb ethdb.Database, config *params.ChainConfig, pow pow.P
 		return nil, err
 	}
 	// Check the current state of the block hashes and make sure that we do not have any of the bad blocks in our chain
-	for hash, _ := range BadHashes {
+	for hash := range BadHashes {
 		if header := bc.GetHeaderByHash(hash); header != nil {
 			// get the canonical block corresponding to the offending header's number
 			headerByNumber := bc.GetHeaderByNumber(header.Number.Uint64())
@@ -402,10 +399,7 @@ func (bc *BlockChain) ResetWithGenesisBlock(genesis *types.Block) {
 
 // Export writes the active chain to the given writer.
 func (self *BlockChain) Export(w io.Writer) error {
-	if err := self.ExportN(w, uint64(0), self.currentBlock.NumberU64()); err != nil {
-		return err
-	}
-	return nil
+	return self.ExportN(w, uint64(0), self.currentBlock.NumberU64())
 }
 
 // ExportN writes a subset of the active chain to the given writer.
diff --git a/core/blockchain_test.go b/core/blockchain_test.go
index 25733ce08..a5a83ba60 100644
--- a/core/blockchain_test.go
+++ b/core/blockchain_test.go
@@ -1107,7 +1107,7 @@ func TestCanonicalBlockRetrieval(t *testing.T) {
 
 	chain, _ := GenerateChain(params.TestChainConfig, genesis, db, 10, func(i int, gen *BlockGen) {})
 
-	for i, _ := range chain {
+	for i := range chain {
 		go func(block *types.Block) {
 			// try to retrieve a block by its canonical hash and see if the block data can be retrieved.
 			for {
diff --git a/core/dao.go b/core/dao.go
index 1260c310a..a7f544c3d 100644
--- a/core/dao.go
+++ b/core/dao.go
@@ -45,11 +45,11 @@ func ValidateDAOHeaderExtraData(config *params.ChainConfig, header *types.Header
 	}
 	// Depending whether we support or oppose the fork, validate the extra-data contents
 	if config.DAOForkSupport {
-		if bytes.Compare(header.Extra, params.DAOForkBlockExtra) != 0 {
+		if !bytes.Equal(header.Extra, params.DAOForkBlockExtra) {
 			return ValidationError("DAO pro-fork bad block extra-data: 0x%x", header.Extra)
 		}
 	} else {
-		if bytes.Compare(header.Extra, params.DAOForkBlockExtra) == 0 {
+		if bytes.Equal(header.Extra, params.DAOForkBlockExtra) {
 			return ValidationError("DAO no-fork bad block extra-data: 0x%x", header.Extra)
 		}
 	}
diff --git a/core/database_util_test.go b/core/database_util_test.go
index c8fd857ea..d96aa71ba 100644
--- a/core/database_util_test.go
+++ b/core/database_util_test.go
@@ -430,7 +430,7 @@ func TestReceiptStorage(t *testing.T) {
 			rlpHave, _ := rlp.EncodeToBytes(r)
 			rlpWant, _ := rlp.EncodeToBytes(receipt)
 
-			if bytes.Compare(rlpHave, rlpWant) != 0 {
+			if !bytes.Equal(rlpHave, rlpWant) {
 				t.Fatalf("receipt #%d [%x]: receipt mismatch: have %v, want %v", i, receipt.TxHash, r, receipt)
 			}
 		}
@@ -488,7 +488,7 @@ func TestBlockReceiptStorage(t *testing.T) {
 			rlpHave, _ := rlp.EncodeToBytes(rs[i])
 			rlpWant, _ := rlp.EncodeToBytes(receipts[i])
 
-			if bytes.Compare(rlpHave, rlpWant) != 0 {
+			if !bytes.Equal(rlpHave, rlpWant) {
 				t.Fatalf("receipt #%d: receipt mismatch: have %v, want %v", i, rs[i], receipts[i])
 			}
 		}
diff --git a/core/state/iterator.go b/core/state/iterator.go
index 14265b277..a58a15ad3 100644
--- a/core/state/iterator.go
+++ b/core/state/iterator.go
@@ -123,7 +123,7 @@ func (it *NodeIterator) step() error {
 	if !it.dataIt.Next() {
 		it.dataIt = nil
 	}
-	if bytes.Compare(account.CodeHash, emptyCodeHash) != 0 {
+	if !bytes.Equal(account.CodeHash, emptyCodeHash) {
 		it.codeHash = common.BytesToHash(account.CodeHash)
 		it.code, err = it.state.db.Get(account.CodeHash)
 		if err != nil {
diff --git a/core/state/iterator_test.go b/core/state/iterator_test.go
index aa05c5dfe..aa9c5b728 100644
--- a/core/state/iterator_test.go
+++ b/core/state/iterator_test.go
@@ -41,7 +41,7 @@ func TestNodeIteratorCoverage(t *testing.T) {
 		}
 	}
 	// Cross check the hashes and the database itself
-	for hash, _ := range hashes {
+	for hash := range hashes {
 		if _, err := db.Get(hash.Bytes()); err != nil {
 			t.Errorf("failed to retrieve reported node %x: %v", hash, err)
 		}
diff --git a/core/state/managed_state_test.go b/core/state/managed_state_test.go
index 3f7bc2aa8..d9c232ebb 100644
--- a/core/state/managed_state_test.go
+++ b/core/state/managed_state_test.go
@@ -52,7 +52,7 @@ func TestRemove(t *testing.T) {
 	ms, account := create()
 
 	nn := make([]bool, 10)
-	for i, _ := range nn {
+	for i := range nn {
 		nn[i] = true
 	}
 	account.nonces = append(account.nonces, nn...)
@@ -68,7 +68,7 @@ func TestReuse(t *testing.T) {
 	ms, account := create()
 
 	nn := make([]bool, 10)
-	for i, _ := range nn {
+	for i := range nn {
 		nn[i] = true
 	}
 	account.nonces = append(account.nonces, nn...)
@@ -84,7 +84,7 @@ func TestReuse(t *testing.T) {
 func TestRemoteNonceChange(t *testing.T) {
 	ms, account := create()
 	nn := make([]bool, 10)
-	for i, _ := range nn {
+	for i := range nn {
 		nn[i] = true
 	}
 	account.nonces = append(account.nonces, nn...)
diff --git a/core/state/statedb.go b/core/state/statedb.go
index bbcde9443..75c40b364 100644
--- a/core/state/statedb.go
+++ b/core/state/statedb.go
@@ -479,7 +479,7 @@ func (self *StateDB) Copy() *StateDB {
 		logSize:           self.logSize,
 	}
 	// Copy the dirty states and logs
-	for addr, _ := range self.stateObjectsDirty {
+	for addr := range self.stateObjectsDirty {
 		state.stateObjects[addr] = self.stateObjects[addr].deepCopy(state, state.MarkStateObjectDirty)
 		state.stateObjectsDirty[addr] = struct{}{}
 	}
@@ -530,7 +530,7 @@ func (self *StateDB) GetRefund() *big.Int {
 // It is called in between transactions to get the root hash that
 // goes into transaction receipts.
 func (s *StateDB) IntermediateRoot(deleteEmptyObjects bool) common.Hash {
-	for addr, _ := range s.stateObjectsDirty {
+	for addr := range s.stateObjectsDirty {
 		stateObject := s.stateObjects[addr]
 		if stateObject.suicided || (deleteEmptyObjects && stateObject.empty()) {
 			s.deleteStateObject(stateObject)
@@ -553,7 +553,7 @@ func (s *StateDB) DeleteSuicides() {
 	// Reset refund so that any used-gas calculations can use this method.
 	s.clearJournalAndRefund()
 
-	for addr, _ := range s.stateObjectsDirty {
+	for addr := range s.stateObjectsDirty {
 		stateObject := s.stateObjects[addr]
 
 		// If the object has been removed by a suicide
diff --git a/core/state/sync_test.go b/core/state/sync_test.go
index 2a30c86f4..43d146e3a 100644
--- a/core/state/sync_test.go
+++ b/core/state/sync_test.go
@@ -84,7 +84,7 @@ func checkStateAccounts(t *testing.T, db ethdb.Database, root common.Hash, accou
 		if nonce := state.GetNonce(acc.address); nonce != acc.nonce {
 			t.Errorf("account %d: nonce mismatch: have %v, want %v", i, nonce, acc.nonce)
 		}
-		if code := state.GetCode(acc.address); bytes.Compare(code, acc.code) != 0 {
+		if code := state.GetCode(acc.address); !bytes.Equal(code, acc.code) {
 			t.Errorf("account %d: code mismatch: have %x, want %x", i, code, acc.code)
 		}
 	}
@@ -198,7 +198,7 @@ func testIterativeRandomStateSync(t *testing.T, batch int) {
 	for len(queue) > 0 {
 		// Fetch all the queued nodes in a random order
 		results := make([]trie.SyncResult, 0, len(queue))
-		for hash, _ := range queue {
+		for hash := range queue {
 			data, err := srcDb.Get(hash.Bytes())
 			if err != nil {
 				t.Fatalf("failed to retrieve node data for %x: %v", hash, err)
@@ -235,7 +235,7 @@ func TestIterativeRandomDelayedStateSync(t *testing.T) {
 	for len(queue) > 0 {
 		// Sync only half of the scheduled nodes, even those in random order
 		results := make([]trie.SyncResult, 0, len(queue)/2+1)
-		for hash, _ := range queue {
+		for hash := range queue {
 			delete(queue, hash)
 
 			data, err := srcDb.Get(hash.Bytes())
@@ -294,7 +294,7 @@ func TestIncompleteStateSync(t *testing.T) {
 			// Skim through the accounts and make sure the root hash is not a code node
 			codeHash := false
 			for _, acc := range srcAccounts {
-				if bytes.Compare(root.Bytes(), crypto.Sha3(acc.code)) == 0 {
+				if root == crypto.Keccak256Hash(acc.code) {
 					codeHash = true
 					break
 				}
diff --git a/core/tx_list.go b/core/tx_list.go
index c3ddf3148..95831c83b 100644
--- a/core/tx_list.go
+++ b/core/tx_list.go
@@ -110,7 +110,7 @@ func (m *txSortedMap) Filter(filter func(*types.Transaction) bool) types.Transac
 	// If transactions were removed, the heap and cache are ruined
 	if len(removed) > 0 {
 		*m.index = make([]uint64, 0, len(m.items))
-		for nonce, _ := range m.items {
+		for nonce := range m.items {
 			*m.index = append(*m.index, nonce)
 		}
 		heap.Init(m.index)
diff --git a/core/tx_pool.go b/core/tx_pool.go
index c5421fa02..2e1e5c63e 100644
--- a/core/tx_pool.go
+++ b/core/tx_pool.go
@@ -609,7 +609,7 @@ func (pool *TxPool) promoteExecutables(state *state.StateDB) {
 	if queued > maxQueuedInTotal {
 		// Sort all accounts with queued transactions by heartbeat
 		addresses := make(addresssByHeartbeat, 0, len(pool.queue))
-		for addr, _ := range pool.queue {
+		for addr := range pool.queue {
 			addresses = append(addresses, addressByHeartbeat{addr, pool.beats[addr]})
 		}
 		sort.Sort(addresses)
diff --git a/core/types/bloom9.go b/core/types/bloom9.go
index bcca59907..32aa47a41 100644
--- a/core/types/bloom9.go
+++ b/core/types/bloom9.go
@@ -97,14 +97,8 @@ func CreateBloom(receipts Receipts) Bloom {
 func LogsBloom(logs []*Log) *big.Int {
 	bin := new(big.Int)
 	for _, log := range logs {
-		data := make([]common.Hash, len(log.Topics))
 		bin.Or(bin, bloom9(log.Address.Bytes()))
-
-		for i, topic := range log.Topics {
-			data[i] = topic
-		}
-
-		for _, b := range data {
+		for _, b := range log.Topics {
 			bin.Or(bin, bloom9(b[:]))
 		}
 	}
diff --git a/core/vm/jump_table.go b/core/vm/jump_table.go
index eb85ae6af..f4ce81883 100644
--- a/core/vm/jump_table.go
+++ b/core/vm/jump_table.go
@@ -52,283 +52,283 @@ var defaultJumpTable = NewJumpTable()
 
 func NewJumpTable() [256]operation {
 	return [256]operation{
-		ADD: operation{
+		ADD: {
 			execute:       opAdd,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		SUB: operation{
+		SUB: {
 			execute:       opSub,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		MUL: operation{
+		MUL: {
 			execute:       opMul,
 			gasCost:       constGasFunc(GasFastStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		DIV: operation{
+		DIV: {
 			execute:       opDiv,
 			gasCost:       constGasFunc(GasFastStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		SDIV: operation{
+		SDIV: {
 			execute:       opSdiv,
 			gasCost:       constGasFunc(GasFastStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		MOD: operation{
+		MOD: {
 			execute:       opMod,
 			gasCost:       constGasFunc(GasFastStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		SMOD: operation{
+		SMOD: {
 			execute:       opSmod,
 			gasCost:       constGasFunc(GasFastStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		EXP: operation{
+		EXP: {
 			execute:       opExp,
 			gasCost:       gasExp,
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		SIGNEXTEND: operation{
+		SIGNEXTEND: {
 			execute:       opSignExtend,
 			gasCost:       constGasFunc(GasFastStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		NOT: operation{
+		NOT: {
 			execute:       opNot,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(1, 1),
 			valid:         true,
 		},
-		LT: operation{
+		LT: {
 			execute:       opLt,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		GT: operation{
+		GT: {
 			execute:       opGt,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		SLT: operation{
+		SLT: {
 			execute:       opSlt,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		SGT: operation{
+		SGT: {
 			execute:       opSgt,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		EQ: operation{
+		EQ: {
 			execute:       opEq,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		ISZERO: operation{
+		ISZERO: {
 			execute:       opIszero,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(1, 1),
 			valid:         true,
 		},
-		AND: operation{
+		AND: {
 			execute:       opAnd,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		OR: operation{
+		OR: {
 			execute:       opOr,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		XOR: operation{
+		XOR: {
 			execute:       opXor,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		BYTE: operation{
+		BYTE: {
 			execute:       opByte,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		ADDMOD: operation{
+		ADDMOD: {
 			execute:       opAddmod,
 			gasCost:       constGasFunc(GasMidStep),
 			validateStack: makeStackFunc(3, 1),
 			valid:         true,
 		},
-		MULMOD: operation{
+		MULMOD: {
 			execute:       opMulmod,
 			gasCost:       constGasFunc(GasMidStep),
 			validateStack: makeStackFunc(3, 1),
 			valid:         true,
 		},
-		SHA3: operation{
+		SHA3: {
 			execute:       opSha3,
 			gasCost:       gasSha3,
 			validateStack: makeStackFunc(2, 1),
 			memorySize:    memorySha3,
 			valid:         true,
 		},
-		ADDRESS: operation{
+		ADDRESS: {
 			execute:       opAddress,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		BALANCE: operation{
+		BALANCE: {
 			execute:       opBalance,
 			gasCost:       gasBalance,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		ORIGIN: operation{
+		ORIGIN: {
 			execute:       opOrigin,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		CALLER: operation{
+		CALLER: {
 			execute:       opCaller,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		CALLVALUE: operation{
+		CALLVALUE: {
 			execute:       opCallValue,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		CALLDATALOAD: operation{
+		CALLDATALOAD: {
 			execute:       opCalldataLoad,
 			gasCost:       constGasFunc(GasFastestStep),
 			validateStack: makeStackFunc(1, 1),
 			valid:         true,
 		},
-		CALLDATASIZE: operation{
+		CALLDATASIZE: {
 			execute:       opCalldataSize,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		CALLDATACOPY: operation{
+		CALLDATACOPY: {
 			execute:       opCalldataCopy,
 			gasCost:       gasCalldataCopy,
 			validateStack: makeStackFunc(3, 1),
 			memorySize:    memoryCalldataCopy,
 			valid:         true,
 		},
-		CODESIZE: operation{
+		CODESIZE: {
 			execute:       opCodeSize,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		EXTCODESIZE: operation{
+		EXTCODESIZE: {
 			execute:       opExtCodeSize,
 			gasCost:       gasExtCodeSize,
 			validateStack: makeStackFunc(1, 1),
 			valid:         true,
 		},
-		CODECOPY: operation{
+		CODECOPY: {
 			execute:       opCodeCopy,
 			gasCost:       gasCodeCopy,
 			validateStack: makeStackFunc(3, 0),
 			memorySize:    memoryCodeCopy,
 			valid:         true,
 		},
-		EXTCODECOPY: operation{
+		EXTCODECOPY: {
 			execute:       opExtCodeCopy,
 			gasCost:       gasExtCodeCopy,
 			validateStack: makeStackFunc(4, 0),
 			memorySize:    memoryExtCodeCopy,
 			valid:         true,
 		},
-		GASPRICE: operation{
+		GASPRICE: {
 			execute:       opGasprice,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		BLOCKHASH: operation{
+		BLOCKHASH: {
 			execute:       opBlockhash,
 			gasCost:       constGasFunc(GasExtStep),
 			validateStack: makeStackFunc(1, 1),
 			valid:         true,
 		},
-		COINBASE: operation{
+		COINBASE: {
 			execute:       opCoinbase,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		TIMESTAMP: operation{
+		TIMESTAMP: {
 			execute:       opTimestamp,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		NUMBER: operation{
+		NUMBER: {
 			execute:       opNumber,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		DIFFICULTY: operation{
+		DIFFICULTY: {
 			execute:       opDifficulty,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		GASLIMIT: operation{
+		GASLIMIT: {
 			execute:       opGasLimit,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		POP: operation{
+		POP: {
 			execute:       opPop,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(1, 0),
 			valid:         true,
 		},
-		MLOAD: operation{
+		MLOAD: {
 			execute:       opMload,
 			gasCost:       gasMLoad,
 			validateStack: makeStackFunc(1, 1),
 			memorySize:    memoryMLoad,
 			valid:         true,
 		},
-		MSTORE: operation{
+		MSTORE: {
 			execute:       opMstore,
 			gasCost:       gasMStore,
 			validateStack: makeStackFunc(2, 0),
 			memorySize:    memoryMStore,
 			valid:         true,
 		},
-		MSTORE8: operation{
+		MSTORE8: {
 			execute:       opMstore8,
 			gasCost:       gasMStore8,
 			memorySize:    memoryMStore8,
@@ -336,71 +336,71 @@ func NewJumpTable() [256]operation {
 
 			valid: true,
 		},
-		SLOAD: operation{
+		SLOAD: {
 			execute:       opSload,
 			gasCost:       gasSLoad,
 			validateStack: makeStackFunc(1, 1),
 			valid:         true,
 		},
-		SSTORE: operation{
+		SSTORE: {
 			execute:       opSstore,
 			gasCost:       gasSStore,
 			validateStack: makeStackFunc(2, 0),
 			valid:         true,
 		},
-		JUMPDEST: operation{
+		JUMPDEST: {
 			execute:       opJumpdest,
 			gasCost:       constGasFunc(params.JumpdestGas),
 			validateStack: makeStackFunc(0, 0),
 			valid:         true,
 		},
-		PC: operation{
+		PC: {
 			execute:       opPc,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		MSIZE: operation{
+		MSIZE: {
 			execute:       opMsize,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		GAS: operation{
+		GAS: {
 			execute:       opGas,
 			gasCost:       constGasFunc(GasQuickStep),
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		CREATE: operation{
+		CREATE: {
 			execute:       opCreate,
 			gasCost:       gasCreate,
 			validateStack: makeStackFunc(3, 1),
 			memorySize:    memoryCreate,
 			valid:         true,
 		},
-		CALL: operation{
+		CALL: {
 			execute:       opCall,
 			gasCost:       gasCall,
 			validateStack: makeStackFunc(7, 1),
 			memorySize:    memoryCall,
 			valid:         true,
 		},
-		CALLCODE: operation{
+		CALLCODE: {
 			execute:       opCallCode,
 			gasCost:       gasCallCode,
 			validateStack: makeStackFunc(7, 1),
 			memorySize:    memoryCall,
 			valid:         true,
 		},
-		DELEGATECALL: operation{
+		DELEGATECALL: {
 			execute:       opDelegateCall,
 			gasCost:       gasDelegateCall,
 			validateStack: makeStackFunc(6, 1),
 			memorySize:    memoryDelegateCall,
 			valid:         true,
 		},
-		RETURN: operation{
+		RETURN: {
 			execute:       opReturn,
 			gasCost:       gasReturn,
 			validateStack: makeStackFunc(2, 0),
@@ -408,448 +408,448 @@ func NewJumpTable() [256]operation {
 			halts:         true,
 			valid:         true,
 		},
-		SUICIDE: operation{
+		SUICIDE: {
 			execute:       opSuicide,
 			gasCost:       gasSuicide,
 			validateStack: makeStackFunc(1, 0),
 			halts:         true,
 			valid:         true,
 		},
-		JUMP: operation{
+		JUMP: {
 			execute:       opJump,
 			gasCost:       constGasFunc(GasMidStep),
 			validateStack: makeStackFunc(1, 0),
 			jumps:         true,
 			valid:         true,
 		},
-		JUMPI: operation{
+		JUMPI: {
 			execute:       opJumpi,
 			gasCost:       constGasFunc(GasSlowStep),
 			validateStack: makeStackFunc(2, 0),
 			jumps:         true,
 			valid:         true,
 		},
-		STOP: operation{
+		STOP: {
 			execute:       opStop,
 			gasCost:       constGasFunc(Zero),
 			validateStack: makeStackFunc(0, 0),
 			halts:         true,
 			valid:         true,
 		},
-		LOG0: operation{
+		LOG0: {
 			execute:       makeLog(0),
 			gasCost:       makeGasLog(0),
 			validateStack: makeStackFunc(2, 0),
 			memorySize:    memoryLog,
 			valid:         true,
 		},
-		LOG1: operation{
+		LOG1: {
 			execute:       makeLog(1),
 			gasCost:       makeGasLog(1),
 			validateStack: makeStackFunc(3, 0),
 			memorySize:    memoryLog,
 			valid:         true,
 		},
-		LOG2: operation{
+		LOG2: {
 			execute:       makeLog(2),
 			gasCost:       makeGasLog(2),
 			validateStack: makeStackFunc(4, 0),
 			memorySize:    memoryLog,
 			valid:         true,
 		},
-		LOG3: operation{
+		LOG3: {
 			execute:       makeLog(3),
 			gasCost:       makeGasLog(3),
 			validateStack: makeStackFunc(5, 0),
 			memorySize:    memoryLog,
 			valid:         true,
 		},
-		LOG4: operation{
+		LOG4: {
 			execute:       makeLog(4),
 			gasCost:       makeGasLog(4),
 			validateStack: makeStackFunc(6, 0),
 			memorySize:    memoryLog,
 			valid:         true,
 		},
-		SWAP1: operation{
+		SWAP1: {
 			execute:       makeSwap(1),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(2, 0),
 			valid:         true,
 		},
-		SWAP2: operation{
+		SWAP2: {
 			execute:       makeSwap(2),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(3, 0),
 			valid:         true,
 		},
-		SWAP3: operation{
+		SWAP3: {
 			execute:       makeSwap(3),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(4, 0),
 			valid:         true,
 		},
-		SWAP4: operation{
+		SWAP4: {
 			execute:       makeSwap(4),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(5, 0),
 			valid:         true,
 		},
-		SWAP5: operation{
+		SWAP5: {
 			execute:       makeSwap(5),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(6, 0),
 			valid:         true,
 		},
-		SWAP6: operation{
+		SWAP6: {
 			execute:       makeSwap(6),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(7, 0),
 			valid:         true,
 		},
-		SWAP7: operation{
+		SWAP7: {
 			execute:       makeSwap(7),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(8, 0),
 			valid:         true,
 		},
-		SWAP8: operation{
+		SWAP8: {
 			execute:       makeSwap(8),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(9, 0),
 			valid:         true,
 		},
-		SWAP9: operation{
+		SWAP9: {
 			execute:       makeSwap(9),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(10, 0),
 			valid:         true,
 		},
-		SWAP10: operation{
+		SWAP10: {
 			execute:       makeSwap(10),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(11, 0),
 			valid:         true,
 		},
-		SWAP11: operation{
+		SWAP11: {
 			execute:       makeSwap(11),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(12, 0),
 			valid:         true,
 		},
-		SWAP12: operation{
+		SWAP12: {
 			execute:       makeSwap(12),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(13, 0),
 			valid:         true,
 		},
-		SWAP13: operation{
+		SWAP13: {
 			execute:       makeSwap(13),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(14, 0),
 			valid:         true,
 		},
-		SWAP14: operation{
+		SWAP14: {
 			execute:       makeSwap(14),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(15, 0),
 			valid:         true,
 		},
-		SWAP15: operation{
+		SWAP15: {
 			execute:       makeSwap(15),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(16, 0),
 			valid:         true,
 		},
-		SWAP16: operation{
+		SWAP16: {
 			execute:       makeSwap(16),
 			gasCost:       gasSwap,
 			validateStack: makeStackFunc(17, 0),
 			valid:         true,
 		},
-		PUSH1: operation{
+		PUSH1: {
 			execute:       makePush(1, big.NewInt(1)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH2: operation{
+		PUSH2: {
 			execute:       makePush(2, big.NewInt(2)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH3: operation{
+		PUSH3: {
 			execute:       makePush(3, big.NewInt(3)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH4: operation{
+		PUSH4: {
 			execute:       makePush(4, big.NewInt(4)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH5: operation{
+		PUSH5: {
 			execute:       makePush(5, big.NewInt(5)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH6: operation{
+		PUSH6: {
 			execute:       makePush(6, big.NewInt(6)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH7: operation{
+		PUSH7: {
 			execute:       makePush(7, big.NewInt(7)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH8: operation{
+		PUSH8: {
 			execute:       makePush(8, big.NewInt(8)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH9: operation{
+		PUSH9: {
 			execute:       makePush(9, big.NewInt(9)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH10: operation{
+		PUSH10: {
 			execute:       makePush(10, big.NewInt(10)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH11: operation{
+		PUSH11: {
 			execute:       makePush(11, big.NewInt(11)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH12: operation{
+		PUSH12: {
 			execute:       makePush(12, big.NewInt(12)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH13: operation{
+		PUSH13: {
 			execute:       makePush(13, big.NewInt(13)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH14: operation{
+		PUSH14: {
 			execute:       makePush(14, big.NewInt(14)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH15: operation{
+		PUSH15: {
 			execute:       makePush(15, big.NewInt(15)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH16: operation{
+		PUSH16: {
 			execute:       makePush(16, big.NewInt(16)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH17: operation{
+		PUSH17: {
 			execute:       makePush(17, big.NewInt(17)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH18: operation{
+		PUSH18: {
 			execute:       makePush(18, big.NewInt(18)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH19: operation{
+		PUSH19: {
 			execute:       makePush(19, big.NewInt(19)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH20: operation{
+		PUSH20: {
 			execute:       makePush(20, big.NewInt(20)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH21: operation{
+		PUSH21: {
 			execute:       makePush(21, big.NewInt(21)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH22: operation{
+		PUSH22: {
 			execute:       makePush(22, big.NewInt(22)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH23: operation{
+		PUSH23: {
 			execute:       makePush(23, big.NewInt(23)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH24: operation{
+		PUSH24: {
 			execute:       makePush(24, big.NewInt(24)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH25: operation{
+		PUSH25: {
 			execute:       makePush(25, big.NewInt(25)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH26: operation{
+		PUSH26: {
 			execute:       makePush(26, big.NewInt(26)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH27: operation{
+		PUSH27: {
 			execute:       makePush(27, big.NewInt(27)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH28: operation{
+		PUSH28: {
 			execute:       makePush(28, big.NewInt(28)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH29: operation{
+		PUSH29: {
 			execute:       makePush(29, big.NewInt(29)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH30: operation{
+		PUSH30: {
 			execute:       makePush(30, big.NewInt(30)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH31: operation{
+		PUSH31: {
 			execute:       makePush(31, big.NewInt(31)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		PUSH32: operation{
+		PUSH32: {
 			execute:       makePush(32, big.NewInt(32)),
 			gasCost:       gasPush,
 			validateStack: makeStackFunc(0, 1),
 			valid:         true,
 		},
-		DUP1: operation{
+		DUP1: {
 			execute:       makeDup(1),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(1, 1),
 			valid:         true,
 		},
-		DUP2: operation{
+		DUP2: {
 			execute:       makeDup(2),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(2, 1),
 			valid:         true,
 		},
-		DUP3: operation{
+		DUP3: {
 			execute:       makeDup(3),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(3, 1),
 			valid:         true,
 		},
-		DUP4: operation{
+		DUP4: {
 			execute:       makeDup(4),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(4, 1),
 			valid:         true,
 		},
-		DUP5: operation{
+		DUP5: {
 			execute:       makeDup(5),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(5, 1),
 			valid:         true,
 		},
-		DUP6: operation{
+		DUP6: {
 			execute:       makeDup(6),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(6, 1),
 			valid:         true,
 		},
-		DUP7: operation{
+		DUP7: {
 			execute:       makeDup(7),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(7, 1),
 			valid:         true,
 		},
-		DUP8: operation{
+		DUP8: {
 			execute:       makeDup(8),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(8, 1),
 			valid:         true,
 		},
-		DUP9: operation{
+		DUP9: {
 			execute:       makeDup(9),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(9, 1),
 			valid:         true,
 		},
-		DUP10: operation{
+		DUP10: {
 			execute:       makeDup(10),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(10, 1),
 			valid:         true,
 		},
-		DUP11: operation{
+		DUP11: {
 			execute:       makeDup(11),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(11, 1),
 			valid:         true,
 		},
-		DUP12: operation{
+		DUP12: {
 			execute:       makeDup(12),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(12, 1),
 			valid:         true,
 		},
-		DUP13: operation{
+		DUP13: {
 			execute:       makeDup(13),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(13, 1),
 			valid:         true,
 		},
-		DUP14: operation{
+		DUP14: {
 			execute:       makeDup(14),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(14, 1),
 			valid:         true,
 		},
-		DUP15: operation{
+		DUP15: {
 			execute:       makeDup(15),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(15, 1),
 			valid:         true,
 		},
-		DUP16: operation{
+		DUP16: {
 			execute:       makeDup(16),
 			gasCost:       gasDup,
 			validateStack: makeStackFunc(16, 1),
diff --git a/crypto/crypto_test.go b/crypto/crypto_test.go
index 86a582306..f42605d32 100644
--- a/crypto/crypto_test.go
+++ b/crypto/crypto_test.go
@@ -217,7 +217,7 @@ func TestValidateSignatureValues(t *testing.T) {
 
 func checkhash(t *testing.T, name string, f func([]byte) []byte, msg, exp []byte) {
 	sum := f(msg)
-	if bytes.Compare(exp, sum) != 0 {
+	if !bytes.Equal(exp, sum) {
 		t.Fatalf("hash %s mismatch: want: %x have: %x", name, exp, sum)
 	}
 }
diff --git a/crypto/ecies/asn1.go b/crypto/ecies/asn1.go
index 40dabd329..508a645cd 100644
--- a/crypto/ecies/asn1.go
+++ b/crypto/ecies/asn1.go
@@ -109,7 +109,7 @@ func (curve secgNamedCurve) Equal(curve2 secgNamedCurve) bool {
 	if len(curve) != len(curve2) {
 		return false
 	}
-	for i, _ := range curve {
+	for i := range curve {
 		if curve[i] != curve2[i] {
 			return false
 		}
@@ -157,7 +157,7 @@ func (a asnAlgorithmIdentifier) Cmp(b asnAlgorithmIdentifier) bool {
 	if len(a.Algorithm) != len(b.Algorithm) {
 		return false
 	}
-	for i, _ := range a.Algorithm {
+	for i := range a.Algorithm {
 		if a.Algorithm[i] != b.Algorithm[i] {
 			return false
 		}
@@ -306,7 +306,7 @@ func (a asnECDHAlgorithm) Cmp(b asnECDHAlgorithm) bool {
 	if len(a.Algorithm) != len(b.Algorithm) {
 		return false
 	}
-	for i, _ := range a.Algorithm {
+	for i := range a.Algorithm {
 		if a.Algorithm[i] != b.Algorithm[i] {
 			return false
 		}
@@ -325,7 +325,7 @@ func (a asnKeyDerivationFunction) Cmp(b asnKeyDerivationFunction) bool {
 	if len(a.Algorithm) != len(b.Algorithm) {
 		return false
 	}
-	for i, _ := range a.Algorithm {
+	for i := range a.Algorithm {
 		if a.Algorithm[i] != b.Algorithm[i] {
 			return false
 		}
@@ -360,7 +360,7 @@ func (a asnSymmetricEncryption) Cmp(b asnSymmetricEncryption) bool {
 	if len(a.Algorithm) != len(b.Algorithm) {
 		return false
 	}
-	for i, _ := range a.Algorithm {
+	for i := range a.Algorithm {
 		if a.Algorithm[i] != b.Algorithm[i] {
 			return false
 		}
@@ -380,7 +380,7 @@ func (a asnMessageAuthenticationCode) Cmp(b asnMessageAuthenticationCode) bool {
 	if len(a.Algorithm) != len(b.Algorithm) {
 		return false
 	}
-	for i, _ := range a.Algorithm {
+	for i := range a.Algorithm {
 		if a.Algorithm[i] != b.Algorithm[i] {
 			return false
 		}
diff --git a/crypto/ecies/ecies.go b/crypto/ecies/ecies.go
index 86a70261d..b1a716c00 100644
--- a/crypto/ecies/ecies.go
+++ b/crypto/ecies/ecies.go
@@ -291,9 +291,8 @@ func Encrypt(rand io.Reader, pub *PublicKey, m, s1, s2 []byte) (ct []byte, err e
 
 // Decrypt decrypts an ECIES ciphertext.
 func (prv *PrivateKey) Decrypt(rand io.Reader, c, s1, s2 []byte) (m []byte, err error) {
-	if c == nil || len(c) == 0 {
-		err = ErrInvalidMessage
-		return
+	if len(c) == 0 {
+		return nil, ErrInvalidMessage
 	}
 	params := prv.PublicKey.Params
 	if params == nil {
diff --git a/crypto/ecies/ecies_test.go b/crypto/ecies/ecies_test.go
index cb09061ce..3b3517baf 100644
--- a/crypto/ecies/ecies_test.go
+++ b/crypto/ecies/ecies_test.go
@@ -492,17 +492,17 @@ type testCase struct {
 }
 
 var testCases = []testCase{
-	testCase{
+	{
 		Curve:    elliptic.P256(),
 		Name:     "P256",
 		Expected: true,
 	},
-	testCase{
+	{
 		Curve:    elliptic.P384(),
 		Name:     "P384",
 		Expected: true,
 	},
-	testCase{
+	{
 		Curve:    elliptic.P521(),
 		Name:     "P521",
 		Expected: true,
diff --git a/crypto/sha3/sha3_test.go b/crypto/sha3/sha3_test.go
index caf72f279..c433761a8 100644
--- a/crypto/sha3/sha3_test.go
+++ b/crypto/sha3/sha3_test.go
@@ -201,7 +201,7 @@ func TestSqueezing(t *testing.T) {
 			d1 := newShakeHash()
 			d1.Write([]byte(testString))
 			var multiple []byte
-			for _ = range ref {
+			for range ref {
 				one := make([]byte, 1)
 				d1.Read(one)
 				multiple = append(multiple, one...)
diff --git a/errs/errors.go b/errs/errors.go
index 675649efa..daa814db7 100644
--- a/errs/errors.go
+++ b/errs/errors.go
@@ -19,7 +19,6 @@ package errs
 import (
 	"fmt"
 
-	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
 )
 
@@ -32,15 +31,10 @@ Fields:
 
  Package:
   name of the package/component
-
- Level:
-  a function mapping error code to logger.LogLevel (severity)
-  if not given, errors default to logger.InfoLevel
 */
 type Errors struct {
 	Errors  map[int]string
 	Package string
-	Level   func(code int) logger.LogLevel
 }
 
 /*
@@ -58,7 +52,6 @@ type Error struct {
 	Code    int
 	Name    string
 	Package string
-	level   logger.LogLevel
 	message string
 	format  string
 	params  []interface{}
@@ -69,15 +62,10 @@ func (self *Errors) New(code int, format string, params ...interface{}) *Error {
 	if !ok {
 		panic("invalid error code")
 	}
-	level := logger.InfoLevel
-	if self.Level != nil {
-		level = self.Level(code)
-	}
 	return &Error{
 		Code:    code,
 		Name:    name,
 		Package: self.Package,
-		level:   level,
 		format:  format,
 		params:  params,
 	}
@@ -98,13 +86,3 @@ func (self Error) Log(v glog.Verbose) {
 		v.Infoln(self)
 	}
 }
-
-/*
-err.Fatal() is true if err's severity level is 0 or 1 (logger.ErrorLevel or logger.Silence)
-*/
-func (self *Error) Fatal() (fatal bool) {
-	if self.level < logger.WarnLevel {
-		fatal = true
-	}
-	return
-}
diff --git a/errs/errors_test.go b/errs/errors_test.go
index d6d14b45e..5a2ffbec3 100644
--- a/errs/errors_test.go
+++ b/errs/errors_test.go
@@ -19,8 +19,6 @@ package errs
 import (
 	"fmt"
 	"testing"
-
-	"github.com/ethereum/go-ethereum/logger"
 )
 
 func testErrors() *Errors {
@@ -30,14 +28,6 @@ func testErrors() *Errors {
 			0: "zero",
 			1: "one",
 		},
-		Level: func(i int) (l logger.LogLevel) {
-			if i == 0 {
-				l = logger.ErrorLevel
-			} else {
-				l = logger.WarnLevel
-			}
-			return
-		},
 	}
 }
 
@@ -49,14 +39,3 @@ func TestErrorMessage(t *testing.T) {
 		t.Errorf("error message incorrect. expected %v, got %v", exp, message)
 	}
 }
-
-func TestErrorSeverity(t *testing.T) {
-	err0 := testErrors().New(0, "zero detail")
-	if !err0.Fatal() {
-		t.Errorf("error should be fatal")
-	}
-	err1 := testErrors().New(1, "one detail")
-	if err1.Fatal() {
-		t.Errorf("error should not be fatal")
-	}
-}
diff --git a/eth/backend_test.go b/eth/backend_test.go
index 8d55f30b9..574731fbe 100644
--- a/eth/backend_test.go
+++ b/eth/backend_test.go
@@ -37,12 +37,12 @@ func TestMipmapUpgrade(t *testing.T) {
 		switch i {
 		case 1:
 			receipt := types.NewReceipt(nil, new(big.Int))
-			receipt.Logs = []*types.Log{&types.Log{Address: addr}}
+			receipt.Logs = []*types.Log{{Address: addr}}
 			gen.AddUncheckedReceipt(receipt)
 			receipts = types.Receipts{receipt}
 		case 2:
 			receipt := types.NewReceipt(nil, new(big.Int))
-			receipt.Logs = []*types.Log{&types.Log{Address: addr}}
+			receipt.Logs = []*types.Log{{Address: addr}}
 			gen.AddUncheckedReceipt(receipt)
 			receipts = types.Receipts{receipt}
 		}
diff --git a/eth/downloader/peer.go b/eth/downloader/peer.go
index b0bfc66c8..ea4b6a6f2 100644
--- a/eth/downloader/peer.go
+++ b/eth/downloader/peer.go
@@ -205,7 +205,7 @@ func (p *peer) FetchNodeData(request *fetchRequest) error {
 
 	// Convert the hash set to a retrievable slice
 	hashes := make([]common.Hash, 0, len(request.Hashes))
-	for hash, _ := range request.Hashes {
+	for hash := range request.Hashes {
 		hashes = append(hashes, hash)
 	}
 	go p.getNodeData(hashes)
@@ -314,7 +314,7 @@ func (p *peer) MarkLacking(hash common.Hash) {
 	defer p.lock.Unlock()
 
 	for len(p.lacking) >= maxLackingHashes {
-		for drop, _ := range p.lacking {
+		for drop := range p.lacking {
 			delete(p.lacking, drop)
 			break
 		}
diff --git a/eth/downloader/queue.go b/eth/downloader/queue.go
index 060eaf970..dd9590b28 100644
--- a/eth/downloader/queue.go
+++ b/eth/downloader/queue.go
@@ -844,7 +844,7 @@ func (q *queue) expire(timeout time.Duration, pendPool map[string]*fetchRequest,
 		}
 	}
 	// Remove the expired requests from the pending pool
-	for id, _ := range expiries {
+	for id := range expiries {
 		delete(pendPool, id)
 	}
 	return expiries
@@ -1063,7 +1063,7 @@ func (q *queue) DeliverNodeData(id string, data [][]byte, callback func(int, boo
 
 	// If no data was retrieved, mark their hashes as unavailable for the origin peer
 	if len(data) == 0 {
-		for hash, _ := range request.Hashes {
+		for hash := range request.Hashes {
 			request.Peer.MarkLacking(hash)
 		}
 	}
diff --git a/eth/filters/api.go b/eth/filters/api.go
index 65d7fd17e..02a544ce1 100644
--- a/eth/filters/api.go
+++ b/eth/filters/api.go
@@ -505,7 +505,7 @@ func (args *FilterCriteria) UnmarshalJSON(data []byte) error {
 			switch topic := t.(type) {
 			case nil:
 				// ignore topic when matching logs
-				args.Topics[i] = []common.Hash{common.Hash{}}
+				args.Topics[i] = []common.Hash{{}}
 
 			case string:
 				// match specific topic
diff --git a/eth/filters/filter_system_test.go b/eth/filters/filter_system_test.go
index 5f51c0aa8..cd0745ec1 100644
--- a/eth/filters/filter_system_test.go
+++ b/eth/filters/filter_system_test.go
@@ -281,15 +281,15 @@ func TestLogFilter(t *testing.T) {
 			// match all
 			0: {FilterCriteria{}, allLogs, ""},
 			// match none due to no matching addresses
-			1: {FilterCriteria{Addresses: []common.Address{common.Address{}, notUsedAddress}, Topics: [][]common.Hash{allLogs[0].Topics}}, []*types.Log{}, ""},
+			1: {FilterCriteria{Addresses: []common.Address{{}, notUsedAddress}, Topics: [][]common.Hash{allLogs[0].Topics}}, []*types.Log{}, ""},
 			// match logs based on addresses, ignore topics
 			2: {FilterCriteria{Addresses: []common.Address{firstAddr}}, allLogs[:2], ""},
 			// match none due to no matching topics (match with address)
-			3: {FilterCriteria{Addresses: []common.Address{secondAddr}, Topics: [][]common.Hash{[]common.Hash{notUsedTopic}}}, []*types.Log{}, ""},
+			3: {FilterCriteria{Addresses: []common.Address{secondAddr}, Topics: [][]common.Hash{{notUsedTopic}}}, []*types.Log{}, ""},
 			// match logs based on addresses and topics
-			4: {FilterCriteria{Addresses: []common.Address{thirdAddress}, Topics: [][]common.Hash{[]common.Hash{firstTopic, secondTopic}}}, allLogs[3:5], ""},
+			4: {FilterCriteria{Addresses: []common.Address{thirdAddress}, Topics: [][]common.Hash{{firstTopic, secondTopic}}}, allLogs[3:5], ""},
 			// match logs based on multiple addresses and "or" topics
-			5: {FilterCriteria{Addresses: []common.Address{secondAddr, thirdAddress}, Topics: [][]common.Hash{[]common.Hash{firstTopic, secondTopic}}}, allLogs[2:5], ""},
+			5: {FilterCriteria{Addresses: []common.Address{secondAddr, thirdAddress}, Topics: [][]common.Hash{{firstTopic, secondTopic}}}, allLogs[2:5], ""},
 			// logs in the pending block
 			6: {FilterCriteria{Addresses: []common.Address{firstAddr}, FromBlock: big.NewInt(rpc.PendingBlockNumber.Int64()), ToBlock: big.NewInt(rpc.PendingBlockNumber.Int64())}, allLogs[:2], ""},
 			// mined logs with block num >= 2 or pending logs
@@ -299,9 +299,9 @@ func TestLogFilter(t *testing.T) {
 			// all "mined" logs
 			9: {FilterCriteria{ToBlock: big.NewInt(rpc.LatestBlockNumber.Int64())}, allLogs, ""},
 			// all "mined" logs with 1>= block num <=2 and topic secondTopic
-			10: {FilterCriteria{FromBlock: big.NewInt(1), ToBlock: big.NewInt(2), Topics: [][]common.Hash{[]common.Hash{secondTopic}}}, allLogs[3:4], ""},
+			10: {FilterCriteria{FromBlock: big.NewInt(1), ToBlock: big.NewInt(2), Topics: [][]common.Hash{{secondTopic}}}, allLogs[3:4], ""},
 			// all "mined" and pending logs with topic firstTopic
-			11: {FilterCriteria{FromBlock: big.NewInt(rpc.LatestBlockNumber.Int64()), ToBlock: big.NewInt(rpc.PendingBlockNumber.Int64()), Topics: [][]common.Hash{[]common.Hash{firstTopic}}}, expectedCase11, ""},
+			11: {FilterCriteria{FromBlock: big.NewInt(rpc.LatestBlockNumber.Int64()), ToBlock: big.NewInt(rpc.PendingBlockNumber.Int64()), Topics: [][]common.Hash{{firstTopic}}}, expectedCase11, ""},
 		}
 	)
 
@@ -402,19 +402,19 @@ func TestPendingLogsSubscription(t *testing.T) {
 			// match all
 			{FilterCriteria{}, convertLogs(allLogs), nil, nil},
 			// match none due to no matching addresses
-			{FilterCriteria{Addresses: []common.Address{common.Address{}, notUsedAddress}, Topics: [][]common.Hash{[]common.Hash{}}}, []*types.Log{}, nil, nil},
+			{FilterCriteria{Addresses: []common.Address{{}, notUsedAddress}, Topics: [][]common.Hash{{}}}, []*types.Log{}, nil, nil},
 			// match logs based on addresses, ignore topics
 			{FilterCriteria{Addresses: []common.Address{firstAddr}}, append(convertLogs(allLogs[:2]), allLogs[5].Logs[3]), nil, nil},
 			// match none due to no matching topics (match with address)
-			{FilterCriteria{Addresses: []common.Address{secondAddr}, Topics: [][]common.Hash{[]common.Hash{notUsedTopic}}}, []*types.Log{}, nil, nil},
+			{FilterCriteria{Addresses: []common.Address{secondAddr}, Topics: [][]common.Hash{{notUsedTopic}}}, []*types.Log{}, nil, nil},
 			// match logs based on addresses and topics
-			{FilterCriteria{Addresses: []common.Address{thirdAddress}, Topics: [][]common.Hash{[]common.Hash{firstTopic, secondTopic}}}, append(convertLogs(allLogs[3:5]), allLogs[5].Logs[0]), nil, nil},
+			{FilterCriteria{Addresses: []common.Address{thirdAddress}, Topics: [][]common.Hash{{firstTopic, secondTopic}}}, append(convertLogs(allLogs[3:5]), allLogs[5].Logs[0]), nil, nil},
 			// match logs based on multiple addresses and "or" topics
-			{FilterCriteria{Addresses: []common.Address{secondAddr, thirdAddress}, Topics: [][]common.Hash{[]common.Hash{firstTopic, secondTopic}}}, append(convertLogs(allLogs[2:5]), allLogs[5].Logs[0]), nil, nil},
+			{FilterCriteria{Addresses: []common.Address{secondAddr, thirdAddress}, Topics: [][]common.Hash{{firstTopic, secondTopic}}}, append(convertLogs(allLogs[2:5]), allLogs[5].Logs[0]), nil, nil},
 			// block numbers are ignored for filters created with New***Filter, these return all logs that match the given criterias when the state changes
 			{FilterCriteria{Addresses: []common.Address{firstAddr}, FromBlock: big.NewInt(2), ToBlock: big.NewInt(3)}, append(convertLogs(allLogs[:2]), allLogs[5].Logs[3]), nil, nil},
 			// multiple pending logs, should match only 2 topics from the logs in block 5
-			{FilterCriteria{Addresses: []common.Address{thirdAddress}, Topics: [][]common.Hash{[]common.Hash{firstTopic, forthTopic}}}, []*types.Log{allLogs[5].Logs[0], allLogs[5].Logs[2]}, nil, nil},
+			{FilterCriteria{Addresses: []common.Address{thirdAddress}, Topics: [][]common.Hash{{firstTopic, forthTopic}}}, []*types.Log{allLogs[5].Logs[0], allLogs[5].Logs[2]}, nil, nil},
 		}
 	)
 
diff --git a/eth/filters/filter_test.go b/eth/filters/filter_test.go
index 35495e8af..83ff3e9ce 100644
--- a/eth/filters/filter_test.go
+++ b/eth/filters/filter_test.go
@@ -210,7 +210,7 @@ func TestFilters(t *testing.T) {
 
 	filter := New(backend, true)
 	filter.SetAddresses([]common.Address{addr})
-	filter.SetTopics([][]common.Hash{[]common.Hash{hash1, hash2, hash3, hash4}})
+	filter.SetTopics([][]common.Hash{{hash1, hash2, hash3, hash4}})
 	filter.SetBeginBlock(0)
 	filter.SetEndBlock(-1)
 
@@ -221,7 +221,7 @@ func TestFilters(t *testing.T) {
 
 	filter = New(backend, true)
 	filter.SetAddresses([]common.Address{addr})
-	filter.SetTopics([][]common.Hash{[]common.Hash{hash3}})
+	filter.SetTopics([][]common.Hash{{hash3}})
 	filter.SetBeginBlock(900)
 	filter.SetEndBlock(999)
 	logs, _ = filter.Find(context.Background())
@@ -234,7 +234,7 @@ func TestFilters(t *testing.T) {
 
 	filter = New(backend, true)
 	filter.SetAddresses([]common.Address{addr})
-	filter.SetTopics([][]common.Hash{[]common.Hash{hash3}})
+	filter.SetTopics([][]common.Hash{{hash3}})
 	filter.SetBeginBlock(990)
 	filter.SetEndBlock(-1)
 	logs, _ = filter.Find(context.Background())
@@ -246,7 +246,7 @@ func TestFilters(t *testing.T) {
 	}
 
 	filter = New(backend, true)
-	filter.SetTopics([][]common.Hash{[]common.Hash{hash1, hash2}})
+	filter.SetTopics([][]common.Hash{{hash1, hash2}})
 	filter.SetBeginBlock(1)
 	filter.SetEndBlock(10)
 
@@ -257,7 +257,7 @@ func TestFilters(t *testing.T) {
 
 	failHash := common.BytesToHash([]byte("fail"))
 	filter = New(backend, true)
-	filter.SetTopics([][]common.Hash{[]common.Hash{failHash}})
+	filter.SetTopics([][]common.Hash{{failHash}})
 	filter.SetBeginBlock(0)
 	filter.SetEndBlock(-1)
 
@@ -278,7 +278,7 @@ func TestFilters(t *testing.T) {
 	}
 
 	filter = New(backend, true)
-	filter.SetTopics([][]common.Hash{[]common.Hash{failHash}, []common.Hash{hash1}})
+	filter.SetTopics([][]common.Hash{{failHash}, {hash1}})
 	filter.SetBeginBlock(0)
 	filter.SetEndBlock(-1)
 
diff --git a/eth/handler.go b/eth/handler.go
index 771e69b8d..1de3f67e6 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -607,38 +607,16 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 		}
 
 	case msg.Code == NewBlockHashesMsg:
-		// Retrieve and deserialize the remote new block hashes notification
-		type announce struct {
-			Hash   common.Hash
-			Number uint64
-		}
-		var announces = []announce{}
-
-		if p.version < eth62 {
-			// We're running the old protocol, make block number unknown (0)
-			var hashes []common.Hash
-			if err := msg.Decode(&hashes); err != nil {
-				return errResp(ErrDecode, "%v: %v", msg, err)
-			}
-			for _, hash := range hashes {
-				announces = append(announces, announce{hash, 0})
-			}
-		} else {
-			// Otherwise extract both block hash and number
-			var request newBlockHashesData
-			if err := msg.Decode(&request); err != nil {
-				return errResp(ErrDecode, "%v: %v", msg, err)
-			}
-			for _, block := range request {
-				announces = append(announces, announce{block.Hash, block.Number})
-			}
+		var announces newBlockHashesData
+		if err := msg.Decode(&announces); err != nil {
+			return errResp(ErrDecode, "%v: %v", msg, err)
 		}
 		// Mark the hashes as present at the remote node
 		for _, block := range announces {
 			p.MarkBlock(block.Hash)
 		}
 		// Schedule all the unknown hashes for retrieval
-		unknown := make([]announce, 0, len(announces))
+		unknown := make(newBlockHashesData, 0, len(announces))
 		for _, block := range announces {
 			if !pm.blockchain.HasBlock(block.Hash) {
 				unknown = append(unknown, block)
diff --git a/eth/handler_test.go b/eth/handler_test.go
index 6900f7808..4695b3f60 100644
--- a/eth/handler_test.go
+++ b/eth/handler_test.go
@@ -75,7 +75,7 @@ func testGetBlockHeaders(t *testing.T, protocol int) {
 
 	// Create a "random" unknown hash for testing
 	var unknown common.Hash
-	for i, _ := range unknown {
+	for i := range unknown {
 		unknown[i] = byte(i)
 	}
 	// Create a batch of tests for various scenarios
@@ -246,17 +246,17 @@ func testGetBlockBodies(t *testing.T, protocol int) {
 		{limit + 1, nil, nil, limit},                                             // No more than the possible block count should be returned
 		{0, []common.Hash{pm.blockchain.Genesis().Hash()}, []bool{true}, 1},      // The genesis block should be retrievable
 		{0, []common.Hash{pm.blockchain.CurrentBlock().Hash()}, []bool{true}, 1}, // The chains head block should be retrievable
-		{0, []common.Hash{common.Hash{}}, []bool{false}, 0},                      // A non existent block should not be returned
+		{0, []common.Hash{{}}, []bool{false}, 0},                                 // A non existent block should not be returned
 
 		// Existing and non-existing blocks interleaved should not cause problems
 		{0, []common.Hash{
-			common.Hash{},
+			{},
 			pm.blockchain.GetBlockByNumber(1).Hash(),
-			common.Hash{},
+			{},
 			pm.blockchain.GetBlockByNumber(10).Hash(),
-			common.Hash{},
+			{},
 			pm.blockchain.GetBlockByNumber(100).Hash(),
-			common.Hash{},
+			{},
 		}, []bool{false, true, false, true, false, true, false}, 3},
 	}
 	// Run each of the tests and verify the results against the chain
diff --git a/eth/protocol_test.go b/eth/protocol_test.go
index 0aac19f43..43149d0c0 100644
--- a/eth/protocol_test.go
+++ b/eth/protocol_test.go
@@ -178,7 +178,7 @@ func testSendTransactions(t *testing.T, protocol int) {
 func TestGetBlockHeadersDataEncodeDecode(t *testing.T) {
 	// Create a "random" hash for testing
 	var hash common.Hash
-	for i, _ := range hash {
+	for i := range hash {
 		hash[i] = byte(i)
 	}
 	// Assemble some table driven tests
diff --git a/ethdb/memory_database.go b/ethdb/memory_database.go
index a729f5233..65c487934 100644
--- a/ethdb/memory_database.go
+++ b/ethdb/memory_database.go
@@ -67,7 +67,7 @@ func (db *MemDatabase) Keys() [][]byte {
 	defer db.lock.RUnlock()
 
 	keys := [][]byte{}
-	for key, _ := range db.db {
+	for key := range db.db {
 		keys = append(keys, []byte(key))
 	}
 	return keys
diff --git a/ethstats/ethstats.go b/ethstats/ethstats.go
index 716beef69..8692a43bd 100644
--- a/ethstats/ethstats.go
+++ b/ethstats/ethstats.go
@@ -326,7 +326,7 @@ func (s *Service) login(in *json.Decoder, out *json.Encoder) error {
 		Secret: s.pass,
 	}
 	login := map[string][]interface{}{
-		"emit": []interface{}{"hello", auth},
+		"emit": {"hello", auth},
 	}
 	if err := out.Encode(login); err != nil {
 		return err
@@ -365,7 +365,7 @@ func (s *Service) reportLatency(out *json.Encoder) error {
 	start := time.Now()
 
 	ping := map[string][]interface{}{
-		"emit": []interface{}{"node-ping", map[string]string{
+		"emit": {"node-ping", map[string]string{
 			"id":         s.node,
 			"clientTime": start.String(),
 		}},
@@ -383,15 +383,12 @@ func (s *Service) reportLatency(out *json.Encoder) error {
 	}
 	// Send back the measured latency
 	latency := map[string][]interface{}{
-		"emit": []interface{}{"latency", map[string]string{
+		"emit": {"latency", map[string]string{
 			"id":      s.node,
 			"latency": strconv.Itoa(int((time.Since(start) / time.Duration(2)).Nanoseconds() / 1000000)),
 		}},
 	}
-	if err := out.Encode(latency); err != nil {
-		return err
-	}
-	return nil
+	return out.Encode(latency)
 }
 
 // blockStats is the information to report about individual blocks.
@@ -438,12 +435,9 @@ func (s *Service) reportBlock(out *json.Encoder, block *types.Block) error {
 		"block": s.assembleBlockStats(block),
 	}
 	report := map[string][]interface{}{
-		"emit": []interface{}{"block", stats},
-	}
-	if err := out.Encode(report); err != nil {
-		return err
+		"emit": {"block", stats},
 	}
-	return nil
+	return out.Encode(report)
 }
 
 // assembleBlockStats retrieves any required metadata to report a single block
@@ -497,9 +491,7 @@ func (s *Service) reportHistory(out *json.Encoder, list []uint64) error {
 	indexes := make([]uint64, 0, historyUpdateRange)
 	if len(list) > 0 {
 		// Specific indexes requested, send them back in particular
-		for _, idx := range list {
-			indexes = append(indexes, idx)
-		}
+		indexes = append(indexes, list...)
 	} else {
 		// No indexes requested, send back the top ones
 		var head *types.Header
@@ -531,12 +523,9 @@ func (s *Service) reportHistory(out *json.Encoder, list []uint64) error {
 		"history": history,
 	}
 	report := map[string][]interface{}{
-		"emit": []interface{}{"history", stats},
-	}
-	if err := out.Encode(report); err != nil {
-		return err
+		"emit": {"history", stats},
 	}
-	return nil
+	return out.Encode(report)
 }
 
 // pendStats is the information to report about pending transactions.
@@ -562,12 +551,9 @@ func (s *Service) reportPending(out *json.Encoder) error {
 		},
 	}
 	report := map[string][]interface{}{
-		"emit": []interface{}{"pending", stats},
-	}
-	if err := out.Encode(report); err != nil {
-		return err
+		"emit": {"pending", stats},
 	}
-	return nil
+	return out.Encode(report)
 }
 
 // blockStats is the information to report about the local node.
@@ -616,10 +602,7 @@ func (s *Service) reportStats(out *json.Encoder) error {
 		},
 	}
 	report := map[string][]interface{}{
-		"emit": []interface{}{"stats", stats},
-	}
-	if err := out.Encode(report); err != nil {
-		return err
+		"emit": {"stats", stats},
 	}
-	return nil
+	return out.Encode(report)
 }
diff --git a/event/event_test.go b/event/event_test.go
index 394029301..2c56ecf29 100644
--- a/event/event_test.go
+++ b/event/event_test.go
@@ -144,7 +144,7 @@ func TestMuxConcurrent(t *testing.T) {
 func emptySubscriber(mux *TypeMux, types ...interface{}) {
 	s := mux.Subscribe(testEvent(0))
 	go func() {
-		for _ = range s.Chan() {
+		for range s.Chan() {
 		}
 	}()
 }
@@ -187,7 +187,7 @@ func BenchmarkChanSend(b *testing.B) {
 	c := make(chan interface{})
 	closed := make(chan struct{})
 	go func() {
-		for _ = range c {
+		for range c {
 		}
 	}()
 
diff --git a/event/filter/generic_filter.go b/event/filter/generic_filter.go
index 27f35920d..d679b8bfa 100644
--- a/event/filter/generic_filter.go
+++ b/event/filter/generic_filter.go
@@ -34,7 +34,7 @@ func (self Generic) Compare(f Filter) bool {
 		strMatch = false
 	}
 
-	for k, _ := range self.Data {
+	for k := range self.Data {
 		if _, ok := filter.Data[k]; !ok {
 			return false
 		}
diff --git a/les/fetcher.go b/les/fetcher.go
index c23af8da3..4a0830a8a 100644
--- a/les/fetcher.go
+++ b/les/fetcher.go
@@ -664,7 +664,7 @@ func (f *lightFetcher) updateMaxConfirmedTd(td *big.Int) {
 			f.lastUpdateStats.next = newEntry
 		}
 		f.lastUpdateStats = newEntry
-		for p, _ := range f.peers {
+		for p := range f.peers {
 			f.checkUpdateStats(p, newEntry)
 		}
 	}
diff --git a/les/flowcontrol/manager.go b/les/flowcontrol/manager.go
index 786884437..f9f029466 100644
--- a/les/flowcontrol/manager.go
+++ b/les/flowcontrol/manager.go
@@ -126,7 +126,7 @@ func (self *ClientManager) removeNode(node *cmNode) {
 // recalc sumWeight
 func (self *ClientManager) updateNodes(time int64) (rce bool) {
 	var sumWeight, rcSum uint64
-	for node, _ := range self.nodes {
+	for node := range self.nodes {
 		rc := node.recharging
 		node.update(time)
 		if rc && !node.recharging {
@@ -145,13 +145,13 @@ func (self *ClientManager) updateNodes(time int64) (rce bool) {
 func (self *ClientManager) update(time int64) {
 	for {
 		firstTime := time
-		for node, _ := range self.nodes {
+		for node := range self.nodes {
 			if node.recharging && node.finishRecharge < firstTime {
 				firstTime = node.finishRecharge
 			}
 		}
 		if self.updateNodes(firstTime) {
-			for node, _ := range self.nodes {
+			for node := range self.nodes {
 				if node.recharging {
 					node.set(node.serving, self.simReqCnt, self.sumWeight)
 				}
diff --git a/les/handler_test.go b/les/handler_test.go
index 37c5dd226..0b94d0d30 100644
--- a/les/handler_test.go
+++ b/les/handler_test.go
@@ -49,7 +49,7 @@ func testGetBlockHeaders(t *testing.T, protocol int) {
 
 	// Create a "random" unknown hash for testing
 	var unknown common.Hash
-	for i, _ := range unknown {
+	for i := range unknown {
 		unknown[i] = byte(i)
 	}
 	// Create a batch of tests for various scenarios
@@ -189,17 +189,17 @@ func testGetBlockBodies(t *testing.T, protocol int) {
 		//{limit + 1, nil, nil, limit},                                  // No more than the possible block count should be returned
 		{0, []common.Hash{bc.Genesis().Hash()}, []bool{true}, 1},      // The genesis block should be retrievable
 		{0, []common.Hash{bc.CurrentBlock().Hash()}, []bool{true}, 1}, // The chains head block should be retrievable
-		{0, []common.Hash{common.Hash{}}, []bool{false}, 0},           // A non existent block should not be returned
+		{0, []common.Hash{{}}, []bool{false}, 0},                      // A non existent block should not be returned
 
 		// Existing and non-existing blocks interleaved should not cause problems
 		{0, []common.Hash{
-			common.Hash{},
+			{},
 			bc.GetBlockByNumber(1).Hash(),
-			common.Hash{},
+			{},
 			bc.GetBlockByNumber(10).Hash(),
-			common.Hash{},
+			{},
 			bc.GetBlockByNumber(100).Hash(),
-			common.Hash{},
+			{},
 		}, []bool{false, true, false, true, false, true, false}, 3},
 	}
 	// Run each of the tests and verify the results against the chain
@@ -312,7 +312,7 @@ func testGetProofs(t *testing.T, protocol int) {
 	var proofreqs []ProofReq
 	var proofs [][]rlp.RawValue
 
-	accounts := []common.Address{testBankAddress, acc1Addr, acc2Addr, common.Address{}}
+	accounts := []common.Address{testBankAddress, acc1Addr, acc2Addr, {}}
 	for i := uint64(0); i <= bc.CurrentBlock().NumberU64(); i++ {
 		header := bc.GetHeaderByNumber(i)
 		root := header.Root
diff --git a/les/peer.go b/les/peer.go
index 0a8db4975..8d4a83f59 100644
--- a/les/peer.go
+++ b/les/peer.go
@@ -467,7 +467,7 @@ func (ps *peerSet) AllPeerIDs() []string {
 
 	res := make([]string, len(ps.peers))
 	idx := 0
-	for id, _ := range ps.peers {
+	for id := range ps.peers {
 		res[idx] = id
 		idx++
 	}
diff --git a/les/randselect_test.go b/les/randselect_test.go
index f3c34305e..9ae7726dd 100644
--- a/les/randselect_test.go
+++ b/les/randselect_test.go
@@ -39,7 +39,7 @@ func TestWeightedRandomSelect(t *testing.T) {
 		s := newWeightedRandomSelect()
 		w := -1
 		list := make([]testWrsItem, cnt)
-		for i, _ := range list {
+		for i := range list {
 			list[i] = testWrsItem{idx: i, widx: &w}
 			s.update(&list[i])
 		}
diff --git a/les/serverpool.go b/les/serverpool.go
index f5e880460..80c446eef 100644
--- a/les/serverpool.go
+++ b/les/serverpool.go
@@ -414,7 +414,7 @@ func (pool *serverPool) loadNodes() {
 // ordered from least to most recently connected.
 func (pool *serverPool) saveNodes() {
 	list := make([]*poolEntry, len(pool.knownQueue.queue))
-	for i, _ := range list {
+	for i := range list {
 		list[i] = pool.knownQueue.fetchOldest()
 	}
 	enc, err := rlp.EncodeToBytes(list)
diff --git a/les/sync.go b/les/sync.go
index 72c979c61..c143cb145 100644
--- a/les/sync.go
+++ b/les/sync.go
@@ -43,12 +43,12 @@ func (pm *ProtocolManager) syncer() {
 	for {
 		select {
 		case <-pm.newPeerCh:
-/*			// Make sure we have peers to select from, then sync
-			if pm.peers.Len() < minDesiredPeerCount {
-				break
-			}
-			go pm.synchronise(pm.peers.BestPeer())
-*/
+			/*			// Make sure we have peers to select from, then sync
+						if pm.peers.Len() < minDesiredPeerCount {
+							break
+						}
+						go pm.synchronise(pm.peers.BestPeer())
+			*/
 		/*case <-forceSync:
 		// Force a sync even if not enough peers are present
 		go pm.synchronise(pm.peers.BestPeer())
diff --git a/les/txrelay.go b/les/txrelay.go
index 036158f5d..84d049b45 100644
--- a/les/txrelay.go
+++ b/les/txrelay.go
@@ -138,7 +138,7 @@ func (self *LesTxRelay) NewHead(head common.Hash, mined []common.Hash, rollback
 	if len(self.txPending) > 0 {
 		txs := make(types.Transactions, len(self.txPending))
 		i := 0
-		for hash, _ := range self.txPending {
+		for hash := range self.txPending {
 			txs[i] = self.txSent[hash].tx
 			i++
 		}
diff --git a/light/lightchain.go b/light/lightchain.go
index d397f5006..0d28ad2f4 100644
--- a/light/lightchain.go
+++ b/light/lightchain.go
@@ -135,7 +135,7 @@ func NewLightChain(odr OdrBackend, config *params.ChainConfig, pow pow.PoW, mux
 		return nil, err
 	}
 	// Check the current state of the block hashes and make sure that we do not have any of the bad blocks in our chain
-	for hash, _ := range core.BadHashes {
+	for hash := range core.BadHashes {
 		if header := bc.GetHeaderByHash(hash); header != nil {
 			glog.V(logger.Error).Infof("Found bad hash, rewinding chain to block #%d [%x…]", header.Number, header.ParentHash[:4])
 			bc.SetHead(header.Number.Uint64() - 1)
diff --git a/light/txpool_test.go b/light/txpool_test.go
index 61d7c1c49..6927c54f8 100644
--- a/light/txpool_test.go
+++ b/light/txpool_test.go
@@ -73,7 +73,7 @@ func txPoolTestChainGen(i int, block *core.BlockGen) {
 }
 
 func TestTxPool(t *testing.T) {
-	for i, _ := range testTx {
+	for i := range testTx {
 		testTx[i], _ = types.SignTx(types.NewTransaction(uint64(i), acc1Addr, big.NewInt(10000), params.TxGas, nil, nil), types.HomesteadSigner{}, testBankKey)
 	}
 
diff --git a/logger/example_test.go b/logger/example_test.go
deleted file mode 100644
index ce5f9da67..000000000
--- a/logger/example_test.go
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright 2014 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package logger
-
-import "os"
-
-func ExampleLogger() {
-	logger := NewLogger("TAG")
-	logger.Infoln("so awesome")            // prints [TAG] so awesome
-	logger.Infof("this %q is raw", "coin") // prints [TAG] this "coin" is raw
-}
-
-func ExampleLogSystem() {
-	filename := "test.log"
-	file, _ := os.OpenFile(filename, os.O_RDWR|os.O_CREATE, os.ModePerm)
-	fileLog := NewStdLogSystem(file, 0, WarnLevel)
-	AddLogSystem(fileLog)
-
-	stdoutLog := NewStdLogSystem(os.Stdout, 0, WarnLevel)
-	AddLogSystem(stdoutLog)
-
-	NewLogger("TAG").Warnln("reactor meltdown") // writes to both logs
-}
diff --git a/logger/glog/glog.go b/logger/glog/glog.go
index edaa21f07..0b33527c3 100644
--- a/logger/glog/glog.go
+++ b/logger/glog/glog.go
@@ -928,7 +928,7 @@ const flushInterval = 30 * time.Second
 
 // flushDaemon periodically flushes the log file buffers.
 func (l *loggingT) flushDaemon() {
-	for _ = range time.NewTicker(flushInterval).C {
+	for range time.NewTicker(flushInterval).C {
 		l.lockAndFlushAll()
 	}
 }
diff --git a/logger/log.go b/logger/log.go
deleted file mode 100644
index 38a6ce139..000000000
--- a/logger/log.go
+++ /dev/null
@@ -1,65 +0,0 @@
-// Copyright 2015 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package logger
-
-import (
-	"fmt"
-	"io"
-	"log"
-	"os"
-
-	"github.com/ethereum/go-ethereum/common"
-)
-
-func openLogFile(datadir string, filename string) *os.File {
-	path := common.AbsolutePath(datadir, filename)
-	file, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
-	if err != nil {
-		panic(fmt.Sprintf("error opening log file '%s': %v", filename, err))
-	}
-	return file
-}
-
-func New(datadir string, logFile string, logLevel int) LogSystem {
-	var writer io.Writer
-	if logFile == "" {
-		writer = os.Stdout
-	} else {
-		writer = openLogFile(datadir, logFile)
-	}
-
-	var sys LogSystem
-	sys = NewStdLogSystem(writer, log.LstdFlags, LogLevel(logLevel))
-	AddLogSystem(sys)
-
-	return sys
-}
-
-func NewJSONsystem(datadir string, logFile string) LogSystem {
-	var writer io.Writer
-	if logFile == "-" {
-		writer = os.Stdout
-	} else {
-		writer = openLogFile(datadir, logFile)
-	}
-
-	var sys LogSystem
-	sys = NewJsonLogSystem(writer)
-	AddLogSystem(sys)
-
-	return sys
-}
diff --git a/logger/loggers.go b/logger/loggers.go
deleted file mode 100644
index e63355d0b..000000000
--- a/logger/loggers.go
+++ /dev/null
@@ -1,149 +0,0 @@
-// Copyright 2014 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-/*
-Package logger implements a multi-output leveled logger.
-
-Other packages use tagged logger to send log messages to shared
-(process-wide) logging engine. The shared logging engine dispatches to
-multiple log systems. The log level can be set separately per log
-system.
-
-Logging is asynchronous and does not block the caller. Message
-formatting is performed by the caller goroutine to avoid incorrect
-logging of mutable state.
-*/
-package logger
-
-import (
-	"encoding/json"
-	"fmt"
-	"os"
-)
-
-type LogLevel uint32
-
-const (
-	// Standard log levels
-	Silence LogLevel = iota
-	ErrorLevel
-	WarnLevel
-	InfoLevel
-	DebugLevel
-	DebugDetailLevel
-)
-
-// A Logger prints messages prefixed by a given tag. It provides named
-// Printf and Println style methods for all loglevels. Each ethereum
-// component should have its own logger with a unique prefix.
-type Logger struct {
-	tag string
-}
-
-func NewLogger(tag string) *Logger {
-	return &Logger{"[" + tag + "] "}
-}
-
-func (logger *Logger) Sendln(level LogLevel, v ...interface{}) {
-	logMessageC <- stdMsg{level, logger.tag + fmt.Sprintln(v...)}
-}
-
-func (logger *Logger) Sendf(level LogLevel, format string, v ...interface{}) {
-	logMessageC <- stdMsg{level, logger.tag + fmt.Sprintf(format, v...)}
-}
-
-// Errorln writes a message with ErrorLevel.
-func (logger *Logger) Errorln(v ...interface{}) {
-	logger.Sendln(ErrorLevel, v...)
-}
-
-// Warnln writes a message with WarnLevel.
-func (logger *Logger) Warnln(v ...interface{}) {
-	logger.Sendln(WarnLevel, v...)
-}
-
-// Infoln writes a message with InfoLevel.
-func (logger *Logger) Infoln(v ...interface{}) {
-	logger.Sendln(InfoLevel, v...)
-}
-
-// Debugln writes a message with DebugLevel.
-func (logger *Logger) Debugln(v ...interface{}) {
-	logger.Sendln(DebugLevel, v...)
-}
-
-// DebugDetailln writes a message with DebugDetailLevel.
-func (logger *Logger) DebugDetailln(v ...interface{}) {
-	logger.Sendln(DebugDetailLevel, v...)
-}
-
-// Errorf writes a message with ErrorLevel.
-func (logger *Logger) Errorf(format string, v ...interface{}) {
-	logger.Sendf(ErrorLevel, format, v...)
-}
-
-// Warnf writes a message with WarnLevel.
-func (logger *Logger) Warnf(format string, v ...interface{}) {
-	logger.Sendf(WarnLevel, format, v...)
-}
-
-// Infof writes a message with InfoLevel.
-func (logger *Logger) Infof(format string, v ...interface{}) {
-	logger.Sendf(InfoLevel, format, v...)
-}
-
-// Debugf writes a message with DebugLevel.
-func (logger *Logger) Debugf(format string, v ...interface{}) {
-	logger.Sendf(DebugLevel, format, v...)
-}
-
-// DebugDetailf writes a message with DebugDetailLevel.
-func (logger *Logger) DebugDetailf(format string, v ...interface{}) {
-	logger.Sendf(DebugDetailLevel, format, v...)
-}
-
-// Fatalln writes a message with ErrorLevel and exits the program.
-func (logger *Logger) Fatalln(v ...interface{}) {
-	logger.Sendln(ErrorLevel, v...)
-	Flush()
-	os.Exit(0)
-}
-
-// Fatalf writes a message with ErrorLevel and exits the program.
-func (logger *Logger) Fatalf(format string, v ...interface{}) {
-	logger.Sendf(ErrorLevel, format, v...)
-	Flush()
-	os.Exit(0)
-}
-
-type JsonLogger struct {
-	Coinbase string
-}
-
-func NewJsonLogger() *JsonLogger {
-	return &JsonLogger{}
-}
-
-func (logger *JsonLogger) LogJson(v JsonLog) {
-	msgname := v.EventName()
-	obj := map[string]interface{}{
-		msgname: v,
-	}
-
-	jsontxt, _ := json.Marshal(obj)
-	logMessageC <- (jsonMsg(jsontxt))
-
-}
diff --git a/logger/loggers_test.go b/logger/loggers_test.go
deleted file mode 100644
index 85564698b..000000000
--- a/logger/loggers_test.go
+++ /dev/null
@@ -1,192 +0,0 @@
-// Copyright 2014 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package logger
-
-import (
-	"io/ioutil"
-	"math/rand"
-	"os"
-	"sync"
-	"testing"
-	"time"
-)
-
-type TestLogSystem struct {
-	mutex  sync.Mutex
-	output string
-	level  LogLevel
-}
-
-func (ls *TestLogSystem) LogPrint(msg LogMsg) {
-	ls.mutex.Lock()
-	if ls.level >= msg.Level() {
-		ls.output += msg.String()
-	}
-	ls.mutex.Unlock()
-}
-
-func (ls *TestLogSystem) SetLogLevel(i LogLevel) {
-	ls.mutex.Lock()
-	ls.level = i
-	ls.mutex.Unlock()
-}
-
-func (ls *TestLogSystem) GetLogLevel() LogLevel {
-	ls.mutex.Lock()
-	defer ls.mutex.Unlock()
-	return ls.level
-}
-
-func (ls *TestLogSystem) CheckOutput(t *testing.T, expected string) {
-	ls.mutex.Lock()
-	output := ls.output
-	ls.mutex.Unlock()
-	if output != expected {
-		t.Errorf("log output mismatch:\n   got: %q\n  want: %q\n", output, expected)
-	}
-}
-
-type blockedLogSystem struct {
-	LogSystem
-	unblock chan struct{}
-}
-
-func (ls blockedLogSystem) LogPrint(msg LogMsg) {
-	<-ls.unblock
-	ls.LogSystem.LogPrint(msg)
-}
-
-func TestLoggerFlush(t *testing.T) {
-	Reset()
-
-	logger := NewLogger("TEST")
-	ls := blockedLogSystem{&TestLogSystem{level: WarnLevel}, make(chan struct{})}
-	AddLogSystem(ls)
-	for i := 0; i < 5; i++ {
-		// these writes shouldn't hang even though ls is blocked
-		logger.Errorf(".")
-	}
-
-	beforeFlush := time.Now()
-	time.AfterFunc(80*time.Millisecond, func() { close(ls.unblock) })
-	Flush() // this should hang for approx. 80ms
-	if blockd := time.Now().Sub(beforeFlush); blockd < 80*time.Millisecond {
-		t.Errorf("Flush didn't block long enough, blocked for %v, should've been >= 80ms", blockd)
-	}
-
-	ls.LogSystem.(*TestLogSystem).CheckOutput(t, "[TEST] .[TEST] .[TEST] .[TEST] .[TEST] .")
-}
-
-func TestLoggerPrintln(t *testing.T) {
-	Reset()
-
-	logger := NewLogger("TEST")
-	testLogSystem := &TestLogSystem{level: WarnLevel}
-	AddLogSystem(testLogSystem)
-	logger.Errorln("error")
-	logger.Warnln("warn")
-	logger.Infoln("info")
-	logger.Debugln("debug")
-	Flush()
-
-	testLogSystem.CheckOutput(t, "[TEST] error\n[TEST] warn\n")
-}
-
-func TestLoggerPrintf(t *testing.T) {
-	Reset()
-
-	logger := NewLogger("TEST")
-	testLogSystem := &TestLogSystem{level: WarnLevel}
-	AddLogSystem(testLogSystem)
-	logger.Errorf("error to %v\n", []int{1, 2, 3})
-	logger.Warnf("warn %%d %d", 5)
-	logger.Infof("info")
-	logger.Debugf("debug")
-	Flush()
-	testLogSystem.CheckOutput(t, "[TEST] error to [1 2 3]\n[TEST] warn %d 5")
-}
-
-func TestMultipleLogSystems(t *testing.T) {
-	Reset()
-
-	logger := NewLogger("TEST")
-	testLogSystem0 := &TestLogSystem{level: ErrorLevel}
-	testLogSystem1 := &TestLogSystem{level: WarnLevel}
-	AddLogSystem(testLogSystem0)
-	AddLogSystem(testLogSystem1)
-	logger.Errorln("error")
-	logger.Warnln("warn")
-	Flush()
-
-	testLogSystem0.CheckOutput(t, "[TEST] error\n")
-	testLogSystem1.CheckOutput(t, "[TEST] error\n[TEST] warn\n")
-}
-
-func TestFileLogSystem(t *testing.T) {
-	Reset()
-
-	logger := NewLogger("TEST")
-	filename := "test.log"
-	file, _ := os.OpenFile(filename, os.O_RDWR|os.O_CREATE, os.ModePerm)
-	testLogSystem := NewStdLogSystem(file, 0, WarnLevel)
-	AddLogSystem(testLogSystem)
-	logger.Errorf("error to %s\n", filename)
-	logger.Warnln("warn")
-	Flush()
-	contents, _ := ioutil.ReadFile(filename)
-	output := string(contents)
-	if output != "[TEST] error to test.log\n[TEST] warn\n" {
-		t.Error("Expected contents of file 'test.log': '[TEST] error to test.log\\n[TEST] warn\\n', got ", output)
-	} else {
-		os.Remove(filename)
-	}
-}
-
-func TestNoLogSystem(t *testing.T) {
-	Reset()
-
-	logger := NewLogger("TEST")
-	logger.Warnln("warn")
-	Flush()
-}
-
-func TestConcurrentAddSystem(t *testing.T) {
-	rand.Seed(time.Now().Unix())
-	Reset()
-
-	logger := NewLogger("TEST")
-	stop := make(chan struct{})
-	writer := func() {
-		select {
-		case <-stop:
-			return
-		default:
-			logger.Infoln("foo")
-			Flush()
-		}
-	}
-
-	go writer()
-	go writer()
-
-	stopTime := time.Now().Add(100 * time.Millisecond)
-	for time.Now().Before(stopTime) {
-		time.Sleep(time.Duration(rand.Intn(20)) * time.Millisecond)
-		AddLogSystem(NewStdLogSystem(ioutil.Discard, 0, InfoLevel))
-	}
-	close(stop)
-}
diff --git a/logger/logsystem.go b/logger/logsystem.go
deleted file mode 100644
index 24f4351d4..000000000
--- a/logger/logsystem.go
+++ /dev/null
@@ -1,76 +0,0 @@
-// Copyright 2015 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package logger
-
-import (
-	"io"
-	"log"
-	"sync/atomic"
-)
-
-// LogSystem is implemented by log output devices.
-// All methods can be called concurrently from multiple goroutines.
-type LogSystem interface {
-	LogPrint(LogMsg)
-}
-
-// NewStdLogSystem creates a LogSystem that prints to the given writer.
-// The flag values are defined package log.
-func NewStdLogSystem(writer io.Writer, flags int, level LogLevel) *StdLogSystem {
-	logger := log.New(writer, "", flags)
-	return &StdLogSystem{logger, uint32(level)}
-}
-
-type StdLogSystem struct {
-	logger *log.Logger
-	level  uint32
-}
-
-func (t *StdLogSystem) LogPrint(msg LogMsg) {
-	stdmsg, ok := msg.(stdMsg)
-	if ok {
-		if t.GetLogLevel() >= stdmsg.Level() {
-			t.logger.Print(stdmsg.String())
-		}
-	}
-}
-
-func (t *StdLogSystem) SetLogLevel(i LogLevel) {
-	atomic.StoreUint32(&t.level, uint32(i))
-}
-
-func (t *StdLogSystem) GetLogLevel() LogLevel {
-	return LogLevel(atomic.LoadUint32(&t.level))
-}
-
-// NewJSONLogSystem creates a LogSystem that prints to the given writer without
-// adding extra information irrespective of loglevel only if message is JSON type
-func NewJsonLogSystem(writer io.Writer) LogSystem {
-	logger := log.New(writer, "", 0)
-	return &jsonLogSystem{logger}
-}
-
-type jsonLogSystem struct {
-	logger *log.Logger
-}
-
-func (t *jsonLogSystem) LogPrint(msg LogMsg) {
-	jsonmsg, ok := msg.(jsonMsg)
-	if ok {
-		t.logger.Print(jsonmsg.String())
-	}
-}
diff --git a/logger/sys.go b/logger/sys.go
deleted file mode 100644
index 18d4ea641..000000000
--- a/logger/sys.go
+++ /dev/null
@@ -1,142 +0,0 @@
-// Copyright 2015 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package logger
-
-import (
-	"fmt"
-	"sync"
-)
-
-type stdMsg struct {
-	level LogLevel
-	msg   string
-}
-
-type jsonMsg []byte
-
-func (m jsonMsg) Level() LogLevel {
-	return 0
-}
-
-func (m jsonMsg) String() string {
-	return string(m)
-}
-
-type LogMsg interface {
-	Level() LogLevel
-	fmt.Stringer
-}
-
-func (m stdMsg) Level() LogLevel {
-	return m.level
-}
-
-func (m stdMsg) String() string {
-	return m.msg
-}
-
-var (
-	logMessageC = make(chan LogMsg)
-	addSystemC  = make(chan LogSystem)
-	flushC      = make(chan chan struct{})
-	resetC      = make(chan chan struct{})
-)
-
-func init() {
-	go dispatchLoop()
-}
-
-// each system can buffer this many messages before
-// blocking incoming log messages.
-const sysBufferSize = 500
-
-func dispatchLoop() {
-	var (
-		systems  []LogSystem
-		systemIn []chan LogMsg
-		systemWG sync.WaitGroup
-	)
-	bootSystem := func(sys LogSystem) {
-		in := make(chan LogMsg, sysBufferSize)
-		systemIn = append(systemIn, in)
-		systemWG.Add(1)
-		go sysLoop(sys, in, &systemWG)
-	}
-
-	for {
-		select {
-		case msg := <-logMessageC:
-			for _, c := range systemIn {
-				c <- msg
-			}
-
-		case sys := <-addSystemC:
-			systems = append(systems, sys)
-			bootSystem(sys)
-
-		case waiter := <-resetC:
-			// reset means terminate all systems
-			for _, c := range systemIn {
-				close(c)
-			}
-			systems = nil
-			systemIn = nil
-			systemWG.Wait()
-			close(waiter)
-
-		case waiter := <-flushC:
-			// flush means reboot all systems
-			for _, c := range systemIn {
-				close(c)
-			}
-			systemIn = nil
-			systemWG.Wait()
-			for _, sys := range systems {
-				bootSystem(sys)
-			}
-			close(waiter)
-		}
-	}
-}
-
-func sysLoop(sys LogSystem, in <-chan LogMsg, wg *sync.WaitGroup) {
-	for msg := range in {
-		sys.LogPrint(msg)
-	}
-	wg.Done()
-}
-
-// Reset removes all active log systems.
-// It blocks until all current messages have been delivered.
-func Reset() {
-	waiter := make(chan struct{})
-	resetC <- waiter
-	<-waiter
-}
-
-// Flush waits until all current log messages have been dispatched to
-// the active log systems.
-func Flush() {
-	waiter := make(chan struct{})
-	flushC <- waiter
-	<-waiter
-}
-
-// AddLogSystem starts printing messages to the given LogSystem.
-func AddLogSystem(sys LogSystem) {
-	addSystemC <- sys
-}
diff --git a/logger/types.go b/logger/types.go
deleted file mode 100644
index ee7e845de..000000000
--- a/logger/types.go
+++ /dev/null
@@ -1,381 +0,0 @@
-// Copyright 2015 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package logger
-
-import (
-	"math/big"
-	"time"
-)
-
-type utctime8601 struct{}
-
-func (utctime8601) MarshalJSON() ([]byte, error) {
-	timestr := time.Now().UTC().Format(time.RFC3339Nano)
-	// Bounds check
-	if len(timestr) > 26 {
-		timestr = timestr[:26]
-	}
-	return []byte(`"` + timestr + `Z"`), nil
-}
-
-type JsonLog interface {
-	EventName() string
-}
-
-type LogEvent struct {
-	// Guid string      `json:"guid"`
-	Ts utctime8601 `json:"ts"`
-	// Level string      `json:"level"`
-}
-
-type LogStarting struct {
-	ClientString    string `json:"client_impl"`
-	ProtocolVersion int    `json:"eth_version"`
-	LogEvent
-}
-
-func (l *LogStarting) EventName() string {
-	return "starting"
-}
-
-type P2PConnected struct {
-	RemoteId            string `json:"remote_id"`
-	RemoteAddress       string `json:"remote_addr"`
-	RemoteVersionString string `json:"remote_version_string"`
-	NumConnections      int    `json:"num_connections"`
-	LogEvent
-}
-
-func (l *P2PConnected) EventName() string {
-	return "p2p.connected"
-}
-
-type P2PDisconnected struct {
-	NumConnections int    `json:"num_connections"`
-	RemoteId       string `json:"remote_id"`
-	LogEvent
-}
-
-func (l *P2PDisconnected) EventName() string {
-	return "p2p.disconnected"
-}
-
-type EthMinerNewBlock struct {
-	BlockHash     string   `json:"block_hash"`
-	BlockNumber   *big.Int `json:"block_number"`
-	ChainHeadHash string   `json:"chain_head_hash"`
-	BlockPrevHash string   `json:"block_prev_hash"`
-	LogEvent
-}
-
-func (l *EthMinerNewBlock) EventName() string {
-	return "eth.miner.new_block"
-}
-
-type EthChainReceivedNewBlock struct {
-	BlockHash     string   `json:"block_hash"`
-	BlockNumber   *big.Int `json:"block_number"`
-	ChainHeadHash string   `json:"chain_head_hash"`
-	BlockPrevHash string   `json:"block_prev_hash"`
-	RemoteId      string   `json:"remote_id"`
-	LogEvent
-}
-
-func (l *EthChainReceivedNewBlock) EventName() string {
-	return "eth.chain.received.new_block"
-}
-
-type EthChainNewHead struct {
-	BlockHash     string   `json:"block_hash"`
-	BlockNumber   *big.Int `json:"block_number"`
-	ChainHeadHash string   `json:"chain_head_hash"`
-	BlockPrevHash string   `json:"block_prev_hash"`
-	LogEvent
-}
-
-func (l *EthChainNewHead) EventName() string {
-	return "eth.chain.new_head"
-}
-
-type EthTxReceived struct {
-	TxHash   string `json:"tx_hash"`
-	RemoteId string `json:"remote_id"`
-	LogEvent
-}
-
-func (l *EthTxReceived) EventName() string {
-	return "eth.tx.received"
-}
-
-//
-//
-// The types below are legacy and need to be converted to new format or deleted
-//
-//
-
-// type P2PConnecting struct {
-// 	RemoteId       string `json:"remote_id"`
-// 	RemoteEndpoint string `json:"remote_endpoint"`
-// 	NumConnections int    `json:"num_connections"`
-// 	LogEvent
-// }
-
-// func (l *P2PConnecting) EventName() string {
-// 	return "p2p.connecting"
-// }
-
-// type P2PHandshaked struct {
-// 	RemoteCapabilities []string `json:"remote_capabilities"`
-// 	RemoteId           string   `json:"remote_id"`
-// 	NumConnections     int      `json:"num_connections"`
-// 	LogEvent
-// }
-
-// func (l *P2PHandshaked) EventName() string {
-// 	return "p2p.handshaked"
-// }
-
-// type P2PDisconnecting struct {
-// 	Reason         string `json:"reason"`
-// 	RemoteId       string `json:"remote_id"`
-// 	NumConnections int    `json:"num_connections"`
-// 	LogEvent
-// }
-
-// func (l *P2PDisconnecting) EventName() string {
-// 	return "p2p.disconnecting"
-// }
-
-// type P2PDisconnectingBadHandshake struct {
-// 	Reason         string `json:"reason"`
-// 	RemoteId       string `json:"remote_id"`
-// 	NumConnections int    `json:"num_connections"`
-// 	LogEvent
-// }
-
-// func (l *P2PDisconnectingBadHandshake) EventName() string {
-// 	return "p2p.disconnecting.bad_handshake"
-// }
-
-// type P2PDisconnectingBadProtocol struct {
-// 	Reason         string `json:"reason"`
-// 	RemoteId       string `json:"remote_id"`
-// 	NumConnections int    `json:"num_connections"`
-// 	LogEvent
-// }
-
-// func (l *P2PDisconnectingBadProtocol) EventName() string {
-// 	return "p2p.disconnecting.bad_protocol"
-// }
-
-// type P2PDisconnectingReputation struct {
-// 	Reason         string `json:"reason"`
-// 	RemoteId       string `json:"remote_id"`
-// 	NumConnections int    `json:"num_connections"`
-// 	LogEvent
-// }
-
-// func (l *P2PDisconnectingReputation) EventName() string {
-// 	return "p2p.disconnecting.reputation"
-// }
-
-// type P2PDisconnectingDHT struct {
-// 	Reason         string `json:"reason"`
-// 	RemoteId       string `json:"remote_id"`
-// 	NumConnections int    `json:"num_connections"`
-// 	LogEvent
-// }
-
-// func (l *P2PDisconnectingDHT) EventName() string {
-// 	return "p2p.disconnecting.dht"
-// }
-
-// type P2PEthDisconnectingBadBlock struct {
-// 	Reason         string `json:"reason"`
-// 	RemoteId       string `json:"remote_id"`
-// 	NumConnections int    `json:"num_connections"`
-// 	LogEvent
-// }
-
-// func (l *P2PEthDisconnectingBadBlock) EventName() string {
-// 	return "p2p.eth.disconnecting.bad_block"
-// }
-
-// type P2PEthDisconnectingBadTx struct {
-// 	Reason         string `json:"reason"`
-// 	RemoteId       string `json:"remote_id"`
-// 	NumConnections int    `json:"num_connections"`
-// 	LogEvent
-// }
-
-// func (l *P2PEthDisconnectingBadTx) EventName() string {
-// 	return "p2p.eth.disconnecting.bad_tx"
-// }
-
-// type EthNewBlockBroadcasted struct {
-// 	BlockNumber     int    `json:"block_number"`
-// 	HeadHash        string `json:"head_hash"`
-// 	BlockHash       string `json:"block_hash"`
-// 	BlockDifficulty int    `json:"block_difficulty"`
-// 	BlockPrevHash   string `json:"block_prev_hash"`
-// 	LogEvent
-// }
-
-// func (l *EthNewBlockBroadcasted) EventName() string {
-// 	return "eth.newblock.broadcasted"
-// }
-
-// type EthNewBlockIsKnown struct {
-// 	BlockNumber     int    `json:"block_number"`
-// 	HeadHash        string `json:"head_hash"`
-// 	BlockHash       string `json:"block_hash"`
-// 	BlockDifficulty int    `json:"block_difficulty"`
-// 	BlockPrevHash   string `json:"block_prev_hash"`
-// 	LogEvent
-// }
-
-// func (l *EthNewBlockIsKnown) EventName() string {
-// 	return "eth.newblock.is_known"
-// }
-
-// type EthNewBlockIsNew struct {
-// 	BlockNumber     int    `json:"block_number"`
-// 	HeadHash        string `json:"head_hash"`
-// 	BlockHash       string `json:"block_hash"`
-// 	BlockDifficulty int    `json:"block_difficulty"`
-// 	BlockPrevHash   string `json:"block_prev_hash"`
-// 	LogEvent
-// }
-
-// func (l *EthNewBlockIsNew) EventName() string {
-// 	return "eth.newblock.is_new"
-// }
-
-// type EthNewBlockMissingParent struct {
-// 	BlockNumber     int    `json:"block_number"`
-// 	HeadHash        string `json:"head_hash"`
-// 	BlockHash       string `json:"block_hash"`
-// 	BlockDifficulty int    `json:"block_difficulty"`
-// 	BlockPrevHash   string `json:"block_prev_hash"`
-// 	LogEvent
-// }
-
-// func (l *EthNewBlockMissingParent) EventName() string {
-// 	return "eth.newblock.missing_parent"
-// }
-
-// type EthNewBlockIsInvalid struct {
-// 	BlockNumber     int    `json:"block_number"`
-// 	HeadHash        string `json:"head_hash"`
-// 	BlockHash       string `json:"block_hash"`
-// 	BlockDifficulty int    `json:"block_difficulty"`
-// 	BlockPrevHash   string `json:"block_prev_hash"`
-// 	LogEvent
-// }
-
-// func (l *EthNewBlockIsInvalid) EventName() string {
-// 	return "eth.newblock.is_invalid"
-// }
-
-// type EthNewBlockChainIsOlder struct {
-// 	BlockNumber     int    `json:"block_number"`
-// 	HeadHash        string `json:"head_hash"`
-// 	BlockHash       string `json:"block_hash"`
-// 	BlockDifficulty int    `json:"block_difficulty"`
-// 	BlockPrevHash   string `json:"block_prev_hash"`
-// 	LogEvent
-// }
-
-// func (l *EthNewBlockChainIsOlder) EventName() string {
-// 	return "eth.newblock.chain.is_older"
-// }
-
-// type EthNewBlockChainIsCanonical struct {
-// 	BlockNumber     int    `json:"block_number"`
-// 	HeadHash        string `json:"head_hash"`
-// 	BlockHash       string `json:"block_hash"`
-// 	BlockDifficulty int    `json:"block_difficulty"`
-// 	BlockPrevHash   string `json:"block_prev_hash"`
-// 	LogEvent
-// }
-
-// func (l *EthNewBlockChainIsCanonical) EventName() string {
-// 	return "eth.newblock.chain.is_cannonical"
-// }
-
-// type EthNewBlockChainNotCanonical struct {
-// 	BlockNumber     int    `json:"block_number"`
-// 	HeadHash        string `json:"head_hash"`
-// 	BlockHash       string `json:"block_hash"`
-// 	BlockDifficulty int    `json:"block_difficulty"`
-// 	BlockPrevHash   string `json:"block_prev_hash"`
-// 	LogEvent
-// }
-
-// func (l *EthNewBlockChainNotCanonical) EventName() string {
-// 	return "eth.newblock.chain.not_cannonical"
-// }
-
-// type EthTxCreated struct {
-// 	TxHash    string `json:"tx_hash"`
-// 	TxSender  string `json:"tx_sender"`
-// 	TxAddress string `json:"tx_address"`
-// 	TxHexRLP  string `json:"tx_hexrlp"`
-// 	TxNonce   int    `json:"tx_nonce"`
-// 	LogEvent
-// }
-
-// func (l *EthTxCreated) EventName() string {
-// 	return "eth.tx.created"
-// }
-
-// type EthTxBroadcasted struct {
-// 	TxHash    string `json:"tx_hash"`
-// 	TxSender  string `json:"tx_sender"`
-// 	TxAddress string `json:"tx_address"`
-// 	TxNonce   int    `json:"tx_nonce"`
-// 	LogEvent
-// }
-
-// func (l *EthTxBroadcasted) EventName() string {
-// 	return "eth.tx.broadcasted"
-// }
-
-// type EthTxValidated struct {
-// 	TxHash    string `json:"tx_hash"`
-// 	TxSender  string `json:"tx_sender"`
-// 	TxAddress string `json:"tx_address"`
-// 	TxNonce   int    `json:"tx_nonce"`
-// 	LogEvent
-// }
-
-// func (l *EthTxValidated) EventName() string {
-// 	return "eth.tx.validated"
-// }
-
-// type EthTxIsInvalid struct {
-// 	TxHash    string `json:"tx_hash"`
-// 	TxSender  string `json:"tx_sender"`
-// 	TxAddress string `json:"tx_address"`
-// 	Reason    string `json:"reason"`
-// 	TxNonce   int    `json:"tx_nonce"`
-// 	LogEvent
-// }
-
-// func (l *EthTxIsInvalid) EventName() string {
-// 	return "eth.tx.is_invalid"
-// }
diff --git a/miner/worker.go b/miner/worker.go
index adb224c47..56fd4ea66 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -39,8 +39,6 @@ import (
 	"gopkg.in/fatih/set.v0"
 )
 
-var jsonlogger = logger.NewJsonLogger()
-
 const (
 	resultQueueSize  = 10
 	miningLogAtDepth = 5
@@ -256,7 +254,7 @@ func (self *worker) update() {
 				self.currentMu.Lock()
 
 				acc, _ := types.Sender(self.current.signer, ev.Tx)
-				txs := map[common.Address]types.Transactions{acc: types.Transactions{ev.Tx}}
+				txs := map[common.Address]types.Transactions{acc: {ev.Tx}}
 				txset := types.NewTransactionsByPriceAndNonce(txs)
 
 				self.current.commitTransactions(self.mux, txset, self.gasPrice, self.chain)
@@ -449,7 +447,7 @@ func (self *worker) commitNewWork() {
 			// Depending whether we support or oppose the fork, override differently
 			if self.config.DAOForkSupport {
 				header.Extra = common.CopyBytes(params.DAOForkBlockExtra)
-			} else if bytes.Compare(header.Extra, params.DAOForkBlockExtra) == 0 {
+			} else if bytes.Equal(header.Extra, params.DAOForkBlockExtra) {
 				header.Extra = []byte{} // If miner opposes, don't let it use the reserved extra-data
 			}
 		}
diff --git a/mobile/bind.go b/mobile/bind.go
index a25c37aca..bc4eb25ba 100644
--- a/mobile/bind.go
+++ b/mobile/bind.go
@@ -114,17 +114,12 @@ type BoundContract struct {
 // DeployContract deploys a contract onto the Ethereum blockchain and binds the
 // deployment address with a wrapper.
 func DeployContract(opts *TransactOpts, abiJSON string, bytecode []byte, client *EthereumClient, args *Interfaces) (contract *BoundContract, _ error) {
-	// Convert all the deployment parameters to Go types
-	params := make([]interface{}, len(args.objects))
-	for i, obj := range args.objects {
-		params[i] = obj
-	}
 	// Deploy the contract to the network
 	parsed, err := abi.JSON(strings.NewReader(abiJSON))
 	if err != nil {
 		return nil, err
 	}
-	addr, tx, bound, err := bind.DeployContract(&opts.opts, parsed, bytecode, client.client, params...)
+	addr, tx, bound, err := bind.DeployContract(&opts.opts, parsed, bytecode, client.client, args.objects...)
 	if err != nil {
 		return nil, err
 	}
@@ -159,32 +154,18 @@ func (c *BoundContract) GetDeployer() *Transaction {
 // Call invokes the (constant) contract method with params as input values and
 // sets the output to result.
 func (c *BoundContract) Call(opts *CallOpts, out *Interfaces, method string, args *Interfaces) error {
-	// Convert all the input and output parameters to Go types
-	params := make([]interface{}, len(args.objects))
-	for i, obj := range args.objects {
-		params[i] = obj
-	}
 	results := make([]interface{}, len(out.objects))
-	for i, obj := range out.objects {
-		results[i] = obj
-	}
-	// Execute the call to the contract and wrap any results
-	if err := c.contract.Call(&opts.opts, &results, method, params...); err != nil {
+	copy(results, out.objects)
+	if err := c.contract.Call(&opts.opts, &results, method, args.objects...); err != nil {
 		return err
 	}
-	for i, res := range results {
-		out.objects[i] = res
-	}
+	copy(out.objects, results)
 	return nil
 }
 
 // Transact invokes the (paid) contract method with params as input values.
 func (c *BoundContract) Transact(opts *TransactOpts, method string, args *Interfaces) (tx *Transaction, _ error) {
-	params := make([]interface{}, len(args.objects))
-	for i, obj := range args.objects {
-		params[i] = obj
-	}
-	rawTx, err := c.contract.Transact(&opts.opts, method, params)
+	rawTx, err := c.contract.Transact(&opts.opts, method, args.objects)
 	if err != nil {
 		return nil, err
 	}
diff --git a/mobile/p2p.go b/mobile/p2p.go
index e717d4004..8d21639e5 100644
--- a/mobile/p2p.go
+++ b/mobile/p2p.go
@@ -38,7 +38,7 @@ func (ni *NodeInfo) GetListenerPort() int       { return ni.info.Ports.Listener
 func (ni *NodeInfo) GetListenerAddress() string { return ni.info.ListenAddr }
 func (ni *NodeInfo) GetProtocols() *Strings {
 	protos := []string{}
-	for proto, _ := range ni.info.Protocols {
+	for proto := range ni.info.Protocols {
 		protos = append(protos, proto)
 	}
 	return &Strings{protos}
diff --git a/node/config_test.go b/node/config_test.go
index b258d2a8b..d18732fdb 100644
--- a/node/config_test.go
+++ b/node/config_test.go
@@ -137,7 +137,7 @@ func TestNodeKeyPersistency(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to read previously persisted node key: %v", err)
 	}
-	if bytes.Compare(blob1, blob2) != 0 {
+	if !bytes.Equal(blob1, blob2) {
 		t.Fatalf("persisted node key mismatch: have %x, want %x", blob2, blob1)
 	}
 
diff --git a/node/node_test.go b/node/node_test.go
index d9b26453b..408d4cfcb 100644
--- a/node/node_test.go
+++ b/node/node_test.go
@@ -166,7 +166,7 @@ func TestServiceLifeCycle(t *testing.T) {
 	if err := stack.Start(); err != nil {
 		t.Fatalf("failed to start protocol stack: %v", err)
 	}
-	for id, _ := range services {
+	for id := range services {
 		if !started[id] {
 			t.Fatalf("service %s: freshly started service not running", id)
 		}
@@ -178,7 +178,7 @@ func TestServiceLifeCycle(t *testing.T) {
 	if err := stack.Stop(); err != nil {
 		t.Fatalf("failed to stop protocol stack: %v", err)
 	}
-	for id, _ := range services {
+	for id := range services {
 		if !stopped[id] {
 			t.Fatalf("service %s: freshly terminated service still running", id)
 		}
@@ -218,7 +218,7 @@ func TestServiceRestarts(t *testing.T) {
 	}
 	defer stack.Stop()
 
-	if running != true || started != 1 {
+	if !running || started != 1 {
 		t.Fatalf("running/started mismatch: have %v/%d, want true/1", running, started)
 	}
 	// Restart the stack a few times and check successful service restarts
@@ -227,7 +227,7 @@ func TestServiceRestarts(t *testing.T) {
 			t.Fatalf("iter %d: failed to restart stack: %v", i, err)
 		}
 	}
-	if running != true || started != 4 {
+	if !running || started != 4 {
 		t.Fatalf("running/started mismatch: have %v/%d, want true/4", running, started)
 	}
 }
@@ -270,7 +270,7 @@ func TestServiceConstructionAbortion(t *testing.T) {
 		if err := stack.Start(); err != failure {
 			t.Fatalf("iter %d: stack startup failure mismatch: have %v, want %v", i, err, failure)
 		}
-		for id, _ := range services {
+		for id := range services {
 			if started[id] {
 				t.Fatalf("service %s: started should not have", id)
 			}
@@ -322,7 +322,7 @@ func TestServiceStartupAbortion(t *testing.T) {
 		if err := stack.Start(); err != failure {
 			t.Fatalf("iter %d: stack startup failure mismatch: have %v, want %v", i, err, failure)
 		}
-		for id, _ := range services {
+		for id := range services {
 			if started[id] && !stopped[id] {
 				t.Fatalf("service %s: started but not stopped", id)
 			}
@@ -376,7 +376,7 @@ func TestServiceTerminationGuarantee(t *testing.T) {
 		if err := stack.Start(); err != nil {
 			t.Fatalf("iter %d: failed to start protocol stack: %v", i, err)
 		}
-		for id, _ := range services {
+		for id := range services {
 			if !started[id] {
 				t.Fatalf("iter %d, service %s: service not running", i, id)
 			}
@@ -397,7 +397,7 @@ func TestServiceTerminationGuarantee(t *testing.T) {
 				t.Fatalf("iter %d: failure count mismatch: have %d, want %d", i, len(err.Services), 1)
 			}
 		}
-		for id, _ := range services {
+		for id := range services {
 			if !stopped[id] {
 				t.Fatalf("iter %d, service %s: service not terminated", i, id)
 			}
diff --git a/p2p/discover/database.go b/p2p/discover/database.go
index d6ea507bb..8d20d1ec7 100644
--- a/p2p/discover/database.go
+++ b/p2p/discover/database.go
@@ -258,7 +258,7 @@ func (db *nodeDB) expireNodes() error {
 			continue
 		}
 		// Skip the node if not expired yet (and not self)
-		if bytes.Compare(id[:], db.self[:]) != 0 {
+		if !bytes.Equal(id[:], db.self[:]) {
 			if seen := db.lastPong(id); seen.After(threshold) {
 				continue
 			}
diff --git a/p2p/discover/database_test.go b/p2p/discover/database_test.go
index 5a729f02b..be972fd2c 100644
--- a/p2p/discover/database_test.go
+++ b/p2p/discover/database_test.go
@@ -242,12 +242,12 @@ func TestNodeDBSeedQuery(t *testing.T) {
 	if len(seeds) != len(want) {
 		t.Errorf("seed count mismatch: have %v, want %v", len(seeds), len(want))
 	}
-	for id, _ := range have {
+	for id := range have {
 		if _, ok := want[id]; !ok {
 			t.Errorf("extra seed: %v", id)
 		}
 	}
-	for id, _ := range want {
+	for id := range want {
 		if _, ok := have[id]; !ok {
 			t.Errorf("missing seed: %v", id)
 		}
diff --git a/p2p/discover/node.go b/p2p/discover/node.go
index eec0bae0c..8b1062d87 100644
--- a/p2p/discover/node.go
+++ b/p2p/discover/node.go
@@ -224,11 +224,8 @@ func (n NodeID) GoString() string {
 // HexID converts a hex string to a NodeID.
 // The string may be prefixed with 0x.
 func HexID(in string) (NodeID, error) {
-	if strings.HasPrefix(in, "0x") {
-		in = in[2:]
-	}
 	var id NodeID
-	b, err := hex.DecodeString(in)
+	b, err := hex.DecodeString(strings.TrimPrefix(in, "0x"))
 	if err != nil {
 		return id, err
 	} else if len(b) != len(id) {
diff --git a/p2p/discover/table.go b/p2p/discover/table.go
index ad0b5c8ca..839e3ec7e 100644
--- a/p2p/discover/table.go
+++ b/p2p/discover/table.go
@@ -433,7 +433,7 @@ func (tab *Table) bondall(nodes []*Node) (result []*Node) {
 			rc <- nn
 		}(nodes[i])
 	}
-	for _ = range nodes {
+	for range nodes {
 		if n := <-rc; n != nil {
 			result = append(result, n)
 		}
diff --git a/p2p/discover/table_test.go b/p2p/discover/table_test.go
index 102c7c2d1..1037cc609 100644
--- a/p2p/discover/table_test.go
+++ b/p2p/discover/table_test.go
@@ -314,19 +314,19 @@ var lookupTestnet = &preminedTestnet{
 	target:    MustHexID("166aea4f556532c6d34e8b740e5d314af7e9ac0ca79833bd751d6b665f12dfd38ec563c363b32f02aef4a80b44fd3def94612d497b99cb5f17fd24de454927ec"),
 	targetSha: common.Hash{0x5c, 0x94, 0x4e, 0xe5, 0x1c, 0x5a, 0xe9, 0xf7, 0x2a, 0x95, 0xec, 0xcb, 0x8a, 0xed, 0x3, 0x74, 0xee, 0xcb, 0x51, 0x19, 0xd7, 0x20, 0xcb, 0xea, 0x68, 0x13, 0xe8, 0xe0, 0xd6, 0xad, 0x92, 0x61},
 	dists: [257][]NodeID{
-		240: []NodeID{
+		240: {
 			MustHexID("2001ad5e3e80c71b952161bc0186731cf5ffe942d24a79230a0555802296238e57ea7a32f5b6f18564eadc1c65389448481f8c9338df0a3dbd18f708cbc2cbcb"),
 			MustHexID("6ba3f4f57d084b6bf94cc4555b8c657e4a8ac7b7baf23c6874efc21dd1e4f56b7eb2721e07f5242d2f1d8381fc8cae535e860197c69236798ba1ad231b105794"),
 		},
-		244: []NodeID{
+		244: {
 			MustHexID("696ba1f0a9d55c59246f776600542a9e6432490f0cd78f8bb55a196918df2081a9b521c3c3ba48e465a75c10768807717f8f689b0b4adce00e1c75737552a178"),
 		},
-		246: []NodeID{
+		246: {
 			MustHexID("d6d32178bdc38416f46ffb8b3ec9e4cb2cfff8d04dd7e4311a70e403cb62b10be1b447311b60b4f9ee221a8131fc2cbd45b96dd80deba68a949d467241facfa8"),
 			MustHexID("3ea3d04a43a3dfb5ac11cffc2319248cf41b6279659393c2f55b8a0a5fc9d12581a9d97ef5d8ff9b5abf3321a290e8f63a4f785f450dc8a672aba3ba2ff4fdab"),
 			MustHexID("2fc897f05ae585553e5c014effd3078f84f37f9333afacffb109f00ca8e7a3373de810a3946be971cbccdfd40249f9fe7f322118ea459ac71acca85a1ef8b7f4"),
 		},
-		247: []NodeID{
+		247: {
 			MustHexID("3155e1427f85f10a5c9a7755877748041af1bcd8d474ec065eb33df57a97babf54bfd2103575fa829115d224c523596b401065a97f74010610fce76382c0bf32"),
 			MustHexID("312c55512422cf9b8a4097e9a6ad79402e87a15ae909a4bfefa22398f03d20951933beea1e4dfa6f968212385e829f04c2d314fc2d4e255e0d3bc08792b069db"),
 			MustHexID("38643200b172dcfef857492156971f0e6aa2c538d8b74010f8e140811d53b98c765dd2d96126051913f44582e8c199ad7c6d6819e9a56483f637feaac9448aac"),
@@ -338,7 +338,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("4ab0a75941b12892369b4490a1928c8ca52a9ad6d3dffbd1d8c0b907bc200fe74c022d011ec39b64808a39c0ca41f1d3254386c3e7733e7044c44259486461b6"),
 			MustHexID("d45150a72dc74388773e68e03133a3b5f51447fe91837d566706b3c035ee4b56f160c878c6273394daee7f56cc398985269052f22f75a8057df2fe6172765354"),
 		},
-		248: []NodeID{
+		248: {
 			MustHexID("6aadfce366a189bab08ac84721567483202c86590642ea6d6a14f37ca78d82bdb6509eb7b8b2f6f63c78ae3ae1d8837c89509e41497d719b23ad53dd81574afa"),
 			MustHexID("a605ecfd6069a4cf4cf7f5840e5bc0ce10d23a3ac59e2aaa70c6afd5637359d2519b4524f56fc2ca180cdbebe54262f720ccaae8c1b28fd553c485675831624d"),
 			MustHexID("29701451cb9448ca33fc33680b44b840d815be90146eb521641efbffed0859c154e8892d3906eae9934bfacee72cd1d2fa9dd050fd18888eea49da155ab0efd2"),
@@ -356,7 +356,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("b76ea1a6fd6506ef6e3506a4f1f60ed6287fff8114af6141b2ff13e61242331b54082b023cfea5b3083354a4fb3f9eb8be01fb4a518f579e731a5d0707291a6b"),
 			MustHexID("9b53a37950ca8890ee349b325032d7b672cab7eced178d3060137b24ef6b92a43977922d5bdfb4a3409a2d80128e02f795f9dae6d7d99973ad0e23a2afb8442f"),
 		},
-		249: []NodeID{
+		249: {
 			MustHexID("675ae65567c3c72c50c73bc0fd4f61f202ea5f93346ca57b551de3411ccc614fad61cb9035493af47615311b9d44ee7a161972ee4d77c28fe1ec029d01434e6a"),
 			MustHexID("8eb81408389da88536ae5800392b16ef5109d7ea132c18e9a82928047ecdb502693f6e4a4cdd18b54296caf561db937185731456c456c98bfe7de0baf0eaa495"),
 			MustHexID("2adba8b1612a541771cb93a726a38a4b88e97b18eced2593eb7daf82f05a5321ca94a72cc780c306ff21e551a932fc2c6d791e4681907b5ceab7f084c3fa2944"),
@@ -374,7 +374,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("d94193f236105010972f5df1b7818b55846592a0445b9cdc4eaed811b8c4c0f7c27dc8cc9837a4774656d6b34682d6d329d42b6ebb55da1d475c2474dc3dfdf4"),
 			MustHexID("edd9af6aded4094e9785637c28fccbd3980cbe28e2eb9a411048a23c2ace4bd6b0b7088a7817997b49a3dd05fc6929ca6c7abbb69438dbdabe65e971d2a794b2"),
 		},
-		250: []NodeID{
+		250: {
 			MustHexID("53a5bd1215d4ab709ae8fdc2ced50bba320bced78bd9c5dc92947fb402250c914891786db0978c898c058493f86fc68b1c5de8a5cb36336150ac7a88655b6c39"),
 			MustHexID("b7f79e3ab59f79262623c9ccefc8f01d682323aee56ffbe295437487e9d5acaf556a9c92e1f1c6a9601f2b9eb6b027ae1aeaebac71d61b9b78e88676efd3e1a3"),
 			MustHexID("d374bf7e8d7ffff69cc00bebff38ef5bc1dcb0a8d51c1a3d70e61ac6b2e2d6617109254b0ac224354dfbf79009fe4239e09020c483cc60c071e00b9238684f30"),
@@ -392,7 +392,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("5b116f0751526868a909b61a30b0c5282c37df6925cc03ddea556ef0d0602a9595fd6c14d371f8ed7d45d89918a032dcd22be4342a8793d88fdbeb3ca3d75bd7"),
 			MustHexID("50f3222fb6b82481c7c813b2172e1daea43e2710a443b9c2a57a12bd160dd37e20f87aa968c82ad639af6972185609d47036c0d93b4b7269b74ebd7073221c10"),
 		},
-		251: []NodeID{
+		251: {
 			MustHexID("9b8f702a62d1bee67bedfeb102eca7f37fa1713e310f0d6651cc0c33ea7c5477575289ccd463e5a2574a00a676a1fdce05658ba447bb9d2827f0ba47b947e894"),
 			MustHexID("b97532eb83054ed054b4abdf413bb30c00e4205545c93521554dbe77faa3cfaa5bd31ef466a107b0b34a71ec97214c0c83919720142cddac93aa7a3e928d4708"),
 			MustHexID("2f7a5e952bfb67f2f90b8441b5fadc9ee13b1dcde3afeeb3dd64bf937f86663cc5c55d1fa83952b5422763c7df1b7f2794b751c6be316ebc0beb4942e65ab8c1"),
@@ -410,7 +410,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("fcc9a2e1ac3667026ff16192876d1813bb75abdbf39b929a92863012fe8b1d890badea7a0de36274d5c1eb1e8f975785532c50d80fd44b1a4b692f437303393f"),
 			MustHexID("6d8b3efb461151dd4f6de809b62726f5b89e9b38e9ba1391967f61cde844f7528fecf821b74049207cee5a527096b31f3ad623928cd3ce51d926fa345a6b2951"),
 		},
-		252: []NodeID{
+		252: {
 			MustHexID("f1ae93157cc48c2075dd5868fbf523e79e06caf4b8198f352f6e526680b78ff4227263de92612f7d63472bd09367bb92a636fff16fe46ccf41614f7a72495c2a"),
 			MustHexID("587f482d111b239c27c0cb89b51dd5d574db8efd8de14a2e6a1400c54d4567e77c65f89c1da52841212080b91604104768350276b6682f2f961cdaf4039581c7"),
 			MustHexID("e3f88274d35cefdaabdf205afe0e80e936cc982b8e3e47a84ce664c413b29016a4fb4f3a3ebae0a2f79671f8323661ed462bf4390af94c424dc8ace0c301b90f"),
@@ -428,7 +428,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("d84f06fe64debc4cd0625e36d19b99014b6218375262cc2209202bdbafd7dffcc4e34ce6398e182e02fd8faeed622c3e175545864902dfd3d1ac57647cddf4c6"),
 			MustHexID("d0ed87b294f38f1d741eb601020eeec30ac16331d05880fe27868f1e454446de367d7457b41c79e202eaf9525b029e4f1d7e17d85a55f83a557c005c68d7328a"),
 		},
-		253: []NodeID{
+		253: {
 			MustHexID("ad4485e386e3cc7c7310366a7c38fb810b8896c0d52e55944bfd320ca294e7912d6c53c0a0cf85e7ce226e92491d60430e86f8f15cda0161ed71893fb4a9e3a1"),
 			MustHexID("36d0e7e5b7734f98c6183eeeb8ac5130a85e910a925311a19c4941b1290f945d4fc3996b12ef4966960b6fa0fb29b1604f83a0f81bd5fd6398d2e1a22e46af0c"),
 			MustHexID("7d307d8acb4a561afa23bdf0bd945d35c90245e26345ec3a1f9f7df354222a7cdcb81339c9ed6744526c27a1a0c8d10857e98df942fa433602facac71ac68a31"),
@@ -446,7 +446,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("7a369b2b8962cc4c65900be046482fbf7c14f98a135bbbae25152c82ad168fb2097b3d1429197cf46d3ce9fdeb64808f908a489cc6019725db040060fdfe5405"),
 			MustHexID("47bcae48288da5ecc7f5058dfa07cf14d89d06d6e449cb946e237aa6652ea050d9f5a24a65efdc0013ccf232bf88670979eddef249b054f63f38da9d7796dbd8"),
 		},
-		254: []NodeID{
+		254: {
 			MustHexID("099739d7abc8abd38ecc7a816c521a1168a4dbd359fa7212a5123ab583ffa1cf485a5fed219575d6475dbcdd541638b2d3631a6c7fce7474e7fe3cba1d4d5853"),
 			MustHexID("c2b01603b088a7182d0cf7ef29fb2b04c70acb320fccf78526bf9472e10c74ee70b3fcfa6f4b11d167bd7d3bc4d936b660f2c9bff934793d97cb21750e7c3d31"),
 			MustHexID("20e4d8f45f2f863e94b45548c1ef22a11f7d36f263e4f8623761e05a64c4572379b000a52211751e2561b0f14f4fc92dd4130410c8ccc71eb4f0e95a700d4ca9"),
@@ -464,7 +464,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("82504b6eb49bb2c0f91a7006ce9cefdbaf6df38706198502c2e06601091fc9dc91e4f15db3410d45c6af355bc270b0f268d3dff560f956985c7332d4b10bd1ed"),
 			MustHexID("b39b5b677b45944ceebe76e76d1f051de2f2a0ec7b0d650da52135743e66a9a5dba45f638258f9a7545d9a790c7fe6d3fdf82c25425c7887323e45d27d06c057"),
 		},
-		255: []NodeID{
+		255: {
 			MustHexID("5c4d58d46e055dd1f093f81ee60a675e1f02f54da6206720adee4dccef9b67a31efc5c2a2949c31a04ee31beadc79aba10da31440a1f9ff2a24093c63c36d784"),
 			MustHexID("ea72161ffdd4b1e124c7b93b0684805f4c4b58d617ed498b37a145c670dbc2e04976f8785583d9c805ffbf343c31d492d79f841652bbbd01b61ed85640b23495"),
 			MustHexID("51caa1d93352d47a8e531692a3612adac1e8ac68d0a200d086c1c57ae1e1a91aa285ab242e8c52ef9d7afe374c9485b122ae815f1707b875569d0433c1c3ce85"),
@@ -482,7 +482,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("f492c6ee2696d5f682f7f537757e52744c2ae560f1090a07024609e903d334e9e174fc01609c5a229ddbcac36c9d21adaf6457dab38a25bfd44f2f0ee4277998"),
 			MustHexID("459e4db99298cb0467a90acee6888b08bb857450deac11015cced5104853be5adce5b69c740968bc7f931495d671a70cad9f48546d7cd203357fe9af0e8d2164"),
 		},
-		256: []NodeID{
+		256: {
 			MustHexID("a8593af8a4aef7b806b5197612017951bac8845a1917ca9a6a15dd6086d608505144990b245785c4cd2d67a295701c7aac2aa18823fb0033987284b019656268"),
 			MustHexID("d2eebef914928c3aad77fc1b2a495f52d2294acf5edaa7d8a530b540f094b861a68fe8348a46a7c302f08ab609d85912a4968eacfea0740847b29421b4795d9e"),
 			MustHexID("b14bfcb31495f32b650b63cf7d08492e3e29071fdc73cf2da0da48d4b191a70ba1a65f42ad8c343206101f00f8a48e8db4b08bf3f622c0853e7323b250835b91"),
diff --git a/p2p/discv5/database.go b/p2p/discv5/database.go
index 7c47c27fd..44be8a74e 100644
--- a/p2p/discv5/database.go
+++ b/p2p/discv5/database.go
@@ -269,7 +269,7 @@ func (db *nodeDB) expireNodes() error {
 			continue
 		}
 		// Skip the node if not expired yet (and not self)
-		if bytes.Compare(id[:], db.self[:]) != 0 {
+		if !bytes.Equal(id[:], db.self[:]) {
 			if seen := db.lastPong(id); seen.After(threshold) {
 				continue
 			}
diff --git a/p2p/discv5/database_test.go b/p2p/discv5/database_test.go
index 4d3330ed2..a2ccb6467 100644
--- a/p2p/discv5/database_test.go
+++ b/p2p/discv5/database_test.go
@@ -242,12 +242,12 @@ func TestNodeDBSeedQuery(t *testing.T) {
 	if len(seeds) != len(want) {
 		t.Errorf("seed count mismatch: have %v, want %v", len(seeds), len(want))
 	}
-	for id, _ := range have {
+	for id := range have {
 		if _, ok := want[id]; !ok {
 			t.Errorf("extra seed: %v", id)
 		}
 	}
-	for id, _ := range want {
+	for id := range want {
 		if _, ok := have[id]; !ok {
 			t.Errorf("missing seed: %v", id)
 		}
diff --git a/p2p/discv5/net_test.go b/p2p/discv5/net_test.go
index 327457c7c..bd234f5ba 100644
--- a/p2p/discv5/net_test.go
+++ b/p2p/discv5/net_test.go
@@ -69,19 +69,19 @@ var lookupTestnet = &preminedTestnet{
 	target:    MustHexID("166aea4f556532c6d34e8b740e5d314af7e9ac0ca79833bd751d6b665f12dfd38ec563c363b32f02aef4a80b44fd3def94612d497b99cb5f17fd24de454927ec"),
 	targetSha: common.Hash{0x5c, 0x94, 0x4e, 0xe5, 0x1c, 0x5a, 0xe9, 0xf7, 0x2a, 0x95, 0xec, 0xcb, 0x8a, 0xed, 0x3, 0x74, 0xee, 0xcb, 0x51, 0x19, 0xd7, 0x20, 0xcb, 0xea, 0x68, 0x13, 0xe8, 0xe0, 0xd6, 0xad, 0x92, 0x61},
 	dists: [257][]NodeID{
-		240: []NodeID{
+		240: {
 			MustHexID("2001ad5e3e80c71b952161bc0186731cf5ffe942d24a79230a0555802296238e57ea7a32f5b6f18564eadc1c65389448481f8c9338df0a3dbd18f708cbc2cbcb"),
 			MustHexID("6ba3f4f57d084b6bf94cc4555b8c657e4a8ac7b7baf23c6874efc21dd1e4f56b7eb2721e07f5242d2f1d8381fc8cae535e860197c69236798ba1ad231b105794"),
 		},
-		244: []NodeID{
+		244: {
 			MustHexID("696ba1f0a9d55c59246f776600542a9e6432490f0cd78f8bb55a196918df2081a9b521c3c3ba48e465a75c10768807717f8f689b0b4adce00e1c75737552a178"),
 		},
-		246: []NodeID{
+		246: {
 			MustHexID("d6d32178bdc38416f46ffb8b3ec9e4cb2cfff8d04dd7e4311a70e403cb62b10be1b447311b60b4f9ee221a8131fc2cbd45b96dd80deba68a949d467241facfa8"),
 			MustHexID("3ea3d04a43a3dfb5ac11cffc2319248cf41b6279659393c2f55b8a0a5fc9d12581a9d97ef5d8ff9b5abf3321a290e8f63a4f785f450dc8a672aba3ba2ff4fdab"),
 			MustHexID("2fc897f05ae585553e5c014effd3078f84f37f9333afacffb109f00ca8e7a3373de810a3946be971cbccdfd40249f9fe7f322118ea459ac71acca85a1ef8b7f4"),
 		},
-		247: []NodeID{
+		247: {
 			MustHexID("3155e1427f85f10a5c9a7755877748041af1bcd8d474ec065eb33df57a97babf54bfd2103575fa829115d224c523596b401065a97f74010610fce76382c0bf32"),
 			MustHexID("312c55512422cf9b8a4097e9a6ad79402e87a15ae909a4bfefa22398f03d20951933beea1e4dfa6f968212385e829f04c2d314fc2d4e255e0d3bc08792b069db"),
 			MustHexID("38643200b172dcfef857492156971f0e6aa2c538d8b74010f8e140811d53b98c765dd2d96126051913f44582e8c199ad7c6d6819e9a56483f637feaac9448aac"),
@@ -93,7 +93,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("4ab0a75941b12892369b4490a1928c8ca52a9ad6d3dffbd1d8c0b907bc200fe74c022d011ec39b64808a39c0ca41f1d3254386c3e7733e7044c44259486461b6"),
 			MustHexID("d45150a72dc74388773e68e03133a3b5f51447fe91837d566706b3c035ee4b56f160c878c6273394daee7f56cc398985269052f22f75a8057df2fe6172765354"),
 		},
-		248: []NodeID{
+		248: {
 			MustHexID("6aadfce366a189bab08ac84721567483202c86590642ea6d6a14f37ca78d82bdb6509eb7b8b2f6f63c78ae3ae1d8837c89509e41497d719b23ad53dd81574afa"),
 			MustHexID("a605ecfd6069a4cf4cf7f5840e5bc0ce10d23a3ac59e2aaa70c6afd5637359d2519b4524f56fc2ca180cdbebe54262f720ccaae8c1b28fd553c485675831624d"),
 			MustHexID("29701451cb9448ca33fc33680b44b840d815be90146eb521641efbffed0859c154e8892d3906eae9934bfacee72cd1d2fa9dd050fd18888eea49da155ab0efd2"),
@@ -111,7 +111,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("b76ea1a6fd6506ef6e3506a4f1f60ed6287fff8114af6141b2ff13e61242331b54082b023cfea5b3083354a4fb3f9eb8be01fb4a518f579e731a5d0707291a6b"),
 			MustHexID("9b53a37950ca8890ee349b325032d7b672cab7eced178d3060137b24ef6b92a43977922d5bdfb4a3409a2d80128e02f795f9dae6d7d99973ad0e23a2afb8442f"),
 		},
-		249: []NodeID{
+		249: {
 			MustHexID("675ae65567c3c72c50c73bc0fd4f61f202ea5f93346ca57b551de3411ccc614fad61cb9035493af47615311b9d44ee7a161972ee4d77c28fe1ec029d01434e6a"),
 			MustHexID("8eb81408389da88536ae5800392b16ef5109d7ea132c18e9a82928047ecdb502693f6e4a4cdd18b54296caf561db937185731456c456c98bfe7de0baf0eaa495"),
 			MustHexID("2adba8b1612a541771cb93a726a38a4b88e97b18eced2593eb7daf82f05a5321ca94a72cc780c306ff21e551a932fc2c6d791e4681907b5ceab7f084c3fa2944"),
@@ -129,7 +129,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("d94193f236105010972f5df1b7818b55846592a0445b9cdc4eaed811b8c4c0f7c27dc8cc9837a4774656d6b34682d6d329d42b6ebb55da1d475c2474dc3dfdf4"),
 			MustHexID("edd9af6aded4094e9785637c28fccbd3980cbe28e2eb9a411048a23c2ace4bd6b0b7088a7817997b49a3dd05fc6929ca6c7abbb69438dbdabe65e971d2a794b2"),
 		},
-		250: []NodeID{
+		250: {
 			MustHexID("53a5bd1215d4ab709ae8fdc2ced50bba320bced78bd9c5dc92947fb402250c914891786db0978c898c058493f86fc68b1c5de8a5cb36336150ac7a88655b6c39"),
 			MustHexID("b7f79e3ab59f79262623c9ccefc8f01d682323aee56ffbe295437487e9d5acaf556a9c92e1f1c6a9601f2b9eb6b027ae1aeaebac71d61b9b78e88676efd3e1a3"),
 			MustHexID("d374bf7e8d7ffff69cc00bebff38ef5bc1dcb0a8d51c1a3d70e61ac6b2e2d6617109254b0ac224354dfbf79009fe4239e09020c483cc60c071e00b9238684f30"),
@@ -147,7 +147,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("5b116f0751526868a909b61a30b0c5282c37df6925cc03ddea556ef0d0602a9595fd6c14d371f8ed7d45d89918a032dcd22be4342a8793d88fdbeb3ca3d75bd7"),
 			MustHexID("50f3222fb6b82481c7c813b2172e1daea43e2710a443b9c2a57a12bd160dd37e20f87aa968c82ad639af6972185609d47036c0d93b4b7269b74ebd7073221c10"),
 		},
-		251: []NodeID{
+		251: {
 			MustHexID("9b8f702a62d1bee67bedfeb102eca7f37fa1713e310f0d6651cc0c33ea7c5477575289ccd463e5a2574a00a676a1fdce05658ba447bb9d2827f0ba47b947e894"),
 			MustHexID("b97532eb83054ed054b4abdf413bb30c00e4205545c93521554dbe77faa3cfaa5bd31ef466a107b0b34a71ec97214c0c83919720142cddac93aa7a3e928d4708"),
 			MustHexID("2f7a5e952bfb67f2f90b8441b5fadc9ee13b1dcde3afeeb3dd64bf937f86663cc5c55d1fa83952b5422763c7df1b7f2794b751c6be316ebc0beb4942e65ab8c1"),
@@ -165,7 +165,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("fcc9a2e1ac3667026ff16192876d1813bb75abdbf39b929a92863012fe8b1d890badea7a0de36274d5c1eb1e8f975785532c50d80fd44b1a4b692f437303393f"),
 			MustHexID("6d8b3efb461151dd4f6de809b62726f5b89e9b38e9ba1391967f61cde844f7528fecf821b74049207cee5a527096b31f3ad623928cd3ce51d926fa345a6b2951"),
 		},
-		252: []NodeID{
+		252: {
 			MustHexID("f1ae93157cc48c2075dd5868fbf523e79e06caf4b8198f352f6e526680b78ff4227263de92612f7d63472bd09367bb92a636fff16fe46ccf41614f7a72495c2a"),
 			MustHexID("587f482d111b239c27c0cb89b51dd5d574db8efd8de14a2e6a1400c54d4567e77c65f89c1da52841212080b91604104768350276b6682f2f961cdaf4039581c7"),
 			MustHexID("e3f88274d35cefdaabdf205afe0e80e936cc982b8e3e47a84ce664c413b29016a4fb4f3a3ebae0a2f79671f8323661ed462bf4390af94c424dc8ace0c301b90f"),
@@ -183,7 +183,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("d84f06fe64debc4cd0625e36d19b99014b6218375262cc2209202bdbafd7dffcc4e34ce6398e182e02fd8faeed622c3e175545864902dfd3d1ac57647cddf4c6"),
 			MustHexID("d0ed87b294f38f1d741eb601020eeec30ac16331d05880fe27868f1e454446de367d7457b41c79e202eaf9525b029e4f1d7e17d85a55f83a557c005c68d7328a"),
 		},
-		253: []NodeID{
+		253: {
 			MustHexID("ad4485e386e3cc7c7310366a7c38fb810b8896c0d52e55944bfd320ca294e7912d6c53c0a0cf85e7ce226e92491d60430e86f8f15cda0161ed71893fb4a9e3a1"),
 			MustHexID("36d0e7e5b7734f98c6183eeeb8ac5130a85e910a925311a19c4941b1290f945d4fc3996b12ef4966960b6fa0fb29b1604f83a0f81bd5fd6398d2e1a22e46af0c"),
 			MustHexID("7d307d8acb4a561afa23bdf0bd945d35c90245e26345ec3a1f9f7df354222a7cdcb81339c9ed6744526c27a1a0c8d10857e98df942fa433602facac71ac68a31"),
@@ -201,7 +201,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("7a369b2b8962cc4c65900be046482fbf7c14f98a135bbbae25152c82ad168fb2097b3d1429197cf46d3ce9fdeb64808f908a489cc6019725db040060fdfe5405"),
 			MustHexID("47bcae48288da5ecc7f5058dfa07cf14d89d06d6e449cb946e237aa6652ea050d9f5a24a65efdc0013ccf232bf88670979eddef249b054f63f38da9d7796dbd8"),
 		},
-		254: []NodeID{
+		254: {
 			MustHexID("099739d7abc8abd38ecc7a816c521a1168a4dbd359fa7212a5123ab583ffa1cf485a5fed219575d6475dbcdd541638b2d3631a6c7fce7474e7fe3cba1d4d5853"),
 			MustHexID("c2b01603b088a7182d0cf7ef29fb2b04c70acb320fccf78526bf9472e10c74ee70b3fcfa6f4b11d167bd7d3bc4d936b660f2c9bff934793d97cb21750e7c3d31"),
 			MustHexID("20e4d8f45f2f863e94b45548c1ef22a11f7d36f263e4f8623761e05a64c4572379b000a52211751e2561b0f14f4fc92dd4130410c8ccc71eb4f0e95a700d4ca9"),
@@ -219,7 +219,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("82504b6eb49bb2c0f91a7006ce9cefdbaf6df38706198502c2e06601091fc9dc91e4f15db3410d45c6af355bc270b0f268d3dff560f956985c7332d4b10bd1ed"),
 			MustHexID("b39b5b677b45944ceebe76e76d1f051de2f2a0ec7b0d650da52135743e66a9a5dba45f638258f9a7545d9a790c7fe6d3fdf82c25425c7887323e45d27d06c057"),
 		},
-		255: []NodeID{
+		255: {
 			MustHexID("5c4d58d46e055dd1f093f81ee60a675e1f02f54da6206720adee4dccef9b67a31efc5c2a2949c31a04ee31beadc79aba10da31440a1f9ff2a24093c63c36d784"),
 			MustHexID("ea72161ffdd4b1e124c7b93b0684805f4c4b58d617ed498b37a145c670dbc2e04976f8785583d9c805ffbf343c31d492d79f841652bbbd01b61ed85640b23495"),
 			MustHexID("51caa1d93352d47a8e531692a3612adac1e8ac68d0a200d086c1c57ae1e1a91aa285ab242e8c52ef9d7afe374c9485b122ae815f1707b875569d0433c1c3ce85"),
@@ -237,7 +237,7 @@ var lookupTestnet = &preminedTestnet{
 			MustHexID("f492c6ee2696d5f682f7f537757e52744c2ae560f1090a07024609e903d334e9e174fc01609c5a229ddbcac36c9d21adaf6457dab38a25bfd44f2f0ee4277998"),
 			MustHexID("459e4db99298cb0467a90acee6888b08bb857450deac11015cced5104853be5adce5b69c740968bc7f931495d671a70cad9f48546d7cd203357fe9af0e8d2164"),
 		},
-		256: []NodeID{
+		256: {
 			MustHexID("a8593af8a4aef7b806b5197612017951bac8845a1917ca9a6a15dd6086d608505144990b245785c4cd2d67a295701c7aac2aa18823fb0033987284b019656268"),
 			MustHexID("d2eebef914928c3aad77fc1b2a495f52d2294acf5edaa7d8a530b540f094b861a68fe8348a46a7c302f08ab609d85912a4968eacfea0740847b29421b4795d9e"),
 			MustHexID("b14bfcb31495f32b650b63cf7d08492e3e29071fdc73cf2da0da48d4b191a70ba1a65f42ad8c343206101f00f8a48e8db4b08bf3f622c0853e7323b250835b91"),
diff --git a/p2p/discv5/node.go b/p2p/discv5/node.go
index b2025ebcb..cfc833ff5 100644
--- a/p2p/discv5/node.go
+++ b/p2p/discv5/node.go
@@ -262,11 +262,8 @@ func (n NodeID) GoString() string {
 // HexID converts a hex string to a NodeID.
 // The string may be prefixed with 0x.
 func HexID(in string) (NodeID, error) {
-	if strings.HasPrefix(in, "0x") {
-		in = in[2:]
-	}
 	var id NodeID
-	b, err := hex.DecodeString(in)
+	b, err := hex.DecodeString(strings.TrimPrefix(in, "0x"))
 	if err != nil {
 		return id, err
 	} else if len(b) != len(id) {
diff --git a/p2p/discv5/sim_test.go b/p2p/discv5/sim_test.go
index cb64d7fa0..3f7fe7463 100644
--- a/p2p/discv5/sim_test.go
+++ b/p2p/discv5/sim_test.go
@@ -74,7 +74,7 @@ func TestSimTopics(t *testing.T) {
 
 	go func() {
 		nets := make([]*Network, 1024)
-		for i, _ := range nets {
+		for i := range nets {
 			net := sim.launchNode(false)
 			nets[i] = net
 			if err := net.SetFallbackNodes([]*Node{bootnode.Self()}); err != nil {
@@ -147,7 +147,7 @@ func TestSimTopics(t *testing.T) {
 func testHierarchicalTopics(i int) []Topic {
 	digits := strconv.FormatInt(int64(128+i/8), 2)
 	res := make([]Topic, 8)
-	for i, _ := range res {
+	for i := range res {
 		res[i] = Topic("foo" + digits[1:i+1])
 	}
 	return res
@@ -167,7 +167,7 @@ func TestSimTopicHierarchy(t *testing.T) {
 
 	go func() {
 		nets := make([]*Network, 1024)
-		for i, _ := range nets {
+		for i := range nets {
 			net := sim.launchNode(false)
 			nets[i] = net
 			if err := net.SetFallbackNodes([]*Node{bootnode.Self()}); err != nil {
diff --git a/p2p/discv5/ticket.go b/p2p/discv5/ticket.go
index 752fdc9b4..48dd114f0 100644
--- a/p2p/discv5/ticket.go
+++ b/p2p/discv5/ticket.go
@@ -831,7 +831,7 @@ func (r *topicRadius) recalcRadius() (radius uint64, radiusLookup int) {
 	maxValue := float64(0)
 	now := mclock.Now()
 	v := float64(0)
-	for i, _ := range r.buckets {
+	for i := range r.buckets {
 		r.buckets[i].update(now)
 		v += r.buckets[i].weights[trOutside] - r.buckets[i].weights[trInside]
 		r.buckets[i].value = v
diff --git a/p2p/discv5/topic.go b/p2p/discv5/topic.go
index 625921e84..b6bea013c 100644
--- a/p2p/discv5/topic.go
+++ b/p2p/discv5/topic.go
@@ -316,7 +316,7 @@ func (t *topicTable) collectGarbage() {
 		t.checkDeleteNode(node)
 	}
 
-	for topic, _ := range t.topics {
+	for topic := range t.topics {
 		t.checkDeleteTopic(topic)
 	}
 }
diff --git a/p2p/nat/natpmp.go b/p2p/nat/natpmp.go
index c2f940891..577a424fb 100644
--- a/p2p/nat/natpmp.go
+++ b/p2p/nat/natpmp.go
@@ -82,7 +82,7 @@ func discoverPMP() Interface {
 	// any responses after a very short timeout.
 	timeout := time.NewTimer(1 * time.Second)
 	defer timeout.Stop()
-	for _ = range gws {
+	for range gws {
 		select {
 		case c := <-found:
 			if c != nil {
diff --git a/p2p/peer_test.go b/p2p/peer_test.go
index 6f96a823b..f44300b15 100644
--- a/p2p/peer_test.go
+++ b/p2p/peer_test.go
@@ -299,7 +299,7 @@ func TestMatchProtocols(t *testing.T) {
 			}
 		}
 		// Make sure no protocols missed negotiation
-		for name, _ := range tt.Match {
+		for name := range tt.Match {
 			if _, ok := result[name]; !ok {
 				t.Errorf("test %d, proto '%s': not negotiated, should have", i, name)
 				continue
diff --git a/p2p/server.go b/p2p/server.go
index cf9672e2d..298148d3e 100644
--- a/p2p/server.go
+++ b/p2p/server.go
@@ -54,8 +54,6 @@ const (
 
 var errServerStopped = errors.New("server stopped")
 
-var srvjslog = logger.NewJsonLogger()
-
 // Config holds Server options.
 type Config struct {
 	// This field must be set to a valid secp256k1 private key.
@@ -737,12 +735,6 @@ func (srv *Server) checkpoint(c *conn, stage chan<- *conn) error {
 // the peer.
 func (srv *Server) runPeer(p *Peer) {
 	glog.V(logger.Debug).Infof("Added %v\n", p)
-	srvjslog.LogJson(&logger.P2PConnected{
-		RemoteId:            p.ID().String(),
-		RemoteAddress:       p.RemoteAddr().String(),
-		RemoteVersionString: p.Name(),
-		NumConnections:      srv.PeerCount(),
-	})
 
 	if srv.newPeerHook != nil {
 		srv.newPeerHook(p)
@@ -753,10 +745,6 @@ func (srv *Server) runPeer(p *Peer) {
 	srv.delpeer <- p
 
 	glog.V(logger.Debug).Infof("Removed %v (%v)\n", p, discreason)
-	srvjslog.LogJson(&logger.P2PDisconnected{
-		RemoteId:       p.ID().String(),
-		NumConnections: srv.PeerCount(),
-	})
 }
 
 // NodeInfo represents a short summary of the information known about the host.
diff --git a/pow/dagger/dagger.go b/pow/dagger/dagger.go
deleted file mode 100644
index f54ba71ca..000000000
--- a/pow/dagger/dagger.go
+++ /dev/null
@@ -1,176 +0,0 @@
-// Copyright 2014 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package dagger
-
-import (
-	"hash"
-	"math/big"
-	"math/rand"
-	"time"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/crypto/sha3"
-	"github.com/ethereum/go-ethereum/logger"
-)
-
-var powlogger = logger.NewLogger("POW")
-
-type Dagger struct {
-	hash *big.Int
-	xn   *big.Int
-}
-
-var Found bool
-
-func (dag *Dagger) Find(obj *big.Int, resChan chan int64) {
-	r := rand.New(rand.NewSource(time.Now().UnixNano()))
-
-	for i := 0; i < 1000; i++ {
-		rnd := r.Int63()
-
-		res := dag.Eval(big.NewInt(rnd))
-		powlogger.Infof("rnd %v\nres %v\nobj %v\n", rnd, res, obj)
-		if res.Cmp(obj) < 0 {
-			// Post back result on the channel
-			resChan <- rnd
-			// Notify other threads we've found a valid nonce
-			Found = true
-		}
-
-		// Break out if found
-		if Found {
-			break
-		}
-	}
-
-	resChan <- 0
-}
-
-func (dag *Dagger) Search(hash, diff *big.Int) (uint64, []byte) {
-	// TODO fix multi threading. Somehow it results in the wrong nonce
-	amountOfRoutines := 1
-
-	dag.hash = hash
-
-	obj := common.BigPow(2, 256)
-	obj = obj.Div(obj, diff)
-
-	Found = false
-	resChan := make(chan int64, 3)
-	var res int64
-
-	for k := 0; k < amountOfRoutines; k++ {
-		go dag.Find(obj, resChan)
-
-		// Wait for each go routine to finish
-	}
-	for k := 0; k < amountOfRoutines; k++ {
-		// Get the result from the channel. 0 = quit
-		if r := <-resChan; r != 0 {
-			res = r
-		}
-	}
-
-	return uint64(res), nil
-}
-
-func (dag *Dagger) Verify(hash, diff, nonce *big.Int) bool {
-	dag.hash = hash
-
-	obj := common.BigPow(2, 256)
-	obj = obj.Div(obj, diff)
-
-	return dag.Eval(nonce).Cmp(obj) < 0
-}
-
-func DaggerVerify(hash, diff, nonce *big.Int) bool {
-	dagger := &Dagger{}
-	dagger.hash = hash
-
-	obj := common.BigPow(2, 256)
-	obj = obj.Div(obj, diff)
-
-	return dagger.Eval(nonce).Cmp(obj) < 0
-}
-
-func (dag *Dagger) Node(L uint64, i uint64) *big.Int {
-	if L == i {
-		return dag.hash
-	}
-
-	var m *big.Int
-	if L == 9 {
-		m = big.NewInt(16)
-	} else {
-		m = big.NewInt(3)
-	}
-
-	sha := sha3.NewKeccak256()
-	sha.Reset()
-	d := sha3.NewKeccak256()
-	b := new(big.Int)
-	ret := new(big.Int)
-
-	for k := 0; k < int(m.Uint64()); k++ {
-		d.Reset()
-		d.Write(dag.hash.Bytes())
-		d.Write(dag.xn.Bytes())
-		d.Write(big.NewInt(int64(L)).Bytes())
-		d.Write(big.NewInt(int64(i)).Bytes())
-		d.Write(big.NewInt(int64(k)).Bytes())
-
-		b.SetBytes(Sum(d))
-		pk := b.Uint64() & ((1 << ((L - 1) * 3)) - 1)
-		sha.Write(dag.Node(L-1, pk).Bytes())
-	}
-
-	ret.SetBytes(Sum(sha))
-
-	return ret
-}
-
-func Sum(sha hash.Hash) []byte {
-	//in := make([]byte, 32)
-	return sha.Sum(nil)
-}
-
-func (dag *Dagger) Eval(N *big.Int) *big.Int {
-	pow := common.BigPow(2, 26)
-	dag.xn = pow.Div(N, pow)
-
-	sha := sha3.NewKeccak256()
-	sha.Reset()
-	ret := new(big.Int)
-
-	for k := 0; k < 4; k++ {
-		d := sha3.NewKeccak256()
-		b := new(big.Int)
-
-		d.Reset()
-		d.Write(dag.hash.Bytes())
-		d.Write(dag.xn.Bytes())
-		d.Write(N.Bytes())
-		d.Write(big.NewInt(int64(k)).Bytes())
-
-		b.SetBytes(Sum(d))
-		pk := (b.Uint64() & 0x1ffffff)
-
-		sha.Write(dag.Node(9, pk).Bytes())
-	}
-
-	return ret.SetBytes(Sum(sha))
-}
diff --git a/pow/dagger/dagger_test.go b/pow/dagger/dagger_test.go
deleted file mode 100644
index 39b74df30..000000000
--- a/pow/dagger/dagger_test.go
+++ /dev/null
@@ -1,35 +0,0 @@
-// Copyright 2014 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package dagger
-
-import (
-	"math/big"
-	"testing"
-
-	"github.com/ethereum/go-ethereum/common"
-)
-
-func BenchmarkDaggerSearch(b *testing.B) {
-	hash := big.NewInt(0)
-	diff := common.BigPow(2, 36)
-	o := big.NewInt(0) // nonce doesn't matter. We're only testing against speed, not validity
-
-	// Reset timer so the big generation isn't included in the benchmark
-	b.ResetTimer()
-	// Validate
-	DaggerVerify(hash, diff, o)
-}
diff --git a/pow/ezp/pow.go b/pow/ezp/pow.go
deleted file mode 100644
index 0f7ee3570..000000000
--- a/pow/ezp/pow.go
+++ /dev/null
@@ -1,113 +0,0 @@
-// Copyright 2014 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package ezp
-
-import (
-	"encoding/binary"
-	"math/big"
-	"math/rand"
-	"time"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/crypto/sha3"
-	"github.com/ethereum/go-ethereum/logger"
-	"github.com/ethereum/go-ethereum/pow"
-)
-
-var powlogger = logger.NewLogger("POW")
-
-type EasyPow struct {
-	hash     *big.Int
-	HashRate int64
-	turbo    bool
-}
-
-func New() *EasyPow {
-	return &EasyPow{turbo: false}
-}
-
-func (pow *EasyPow) GetHashrate() int64 {
-	return pow.HashRate
-}
-
-func (pow *EasyPow) Turbo(on bool) {
-	pow.turbo = on
-}
-
-func (pow *EasyPow) Search(block pow.Block, stop <-chan struct{}, index int) (uint64, []byte) {
-	r := rand.New(rand.NewSource(time.Now().UnixNano()))
-	hash := block.HashNoNonce()
-	diff := block.Difficulty()
-	//i := int64(0)
-	// TODO fix offset
-	i := rand.Int63()
-	starti := i
-	start := time.Now().UnixNano()
-
-	defer func() { pow.HashRate = 0 }()
-
-	// Make sure stop is empty
-empty:
-	for {
-		select {
-		case <-stop:
-		default:
-			break empty
-		}
-	}
-
-	for {
-		select {
-		case <-stop:
-			return 0, nil
-		default:
-			i++
-
-			elapsed := time.Now().UnixNano() - start
-			hashes := ((float64(1e9) / float64(elapsed)) * float64(i-starti)) / 1000
-			pow.HashRate = int64(hashes)
-
-			sha := uint64(r.Int63())
-			if verify(hash, diff, sha) {
-				return sha, nil
-			}
-		}
-
-		if !pow.turbo {
-			time.Sleep(20 * time.Microsecond)
-		}
-	}
-}
-
-func (pow *EasyPow) Verify(block pow.Block) bool {
-	return Verify(block)
-}
-
-func verify(hash common.Hash, diff *big.Int, nonce uint64) bool {
-	sha := sha3.NewKeccak256()
-	n := make([]byte, 8)
-	binary.PutUvarint(n, nonce)
-	sha.Write(n)
-	sha.Write(hash[:])
-	verification := new(big.Int).Div(common.BigPow(2, 256), diff)
-	res := common.BigD(sha.Sum(nil))
-	return res.Cmp(verification) <= 0
-}
-
-func Verify(block pow.Block) bool {
-	return verify(block.HashNoNonce(), block.Difficulty(), block.Nonce())
-}
diff --git a/rpc/json.go b/rpc/json.go
index ac5a4acd3..61a4ddf43 100644
--- a/rpc/json.go
+++ b/rpc/json.go
@@ -166,7 +166,7 @@ func parseRequest(incomingMsg json.RawMessage) ([]rpcRequest, bool, Error) {
 
 	// subscribe are special, they will always use `subscribeMethod` as first param in the payload
 	if in.Method == subscribeMethod {
-		reqs := []rpcRequest{rpcRequest{id: &in.Id, isPubSub: true}}
+		reqs := []rpcRequest{{id: &in.Id, isPubSub: true}}
 		if len(in.Payload) > 0 {
 			// first param must be subscription name
 			var subscribeMethod [1]string
@@ -184,7 +184,7 @@ func parseRequest(incomingMsg json.RawMessage) ([]rpcRequest, bool, Error) {
 	}
 
 	if in.Method == unsubscribeMethod {
-		return []rpcRequest{rpcRequest{id: &in.Id, isPubSub: true,
+		return []rpcRequest{{id: &in.Id, isPubSub: true,
 			method: unsubscribeMethod, params: in.Payload}}, false, nil
 	}
 
@@ -195,10 +195,10 @@ func parseRequest(incomingMsg json.RawMessage) ([]rpcRequest, bool, Error) {
 
 	// regular RPC call
 	if len(in.Payload) == 0 {
-		return []rpcRequest{rpcRequest{service: elems[0], method: elems[1], id: &in.Id}}, false, nil
+		return []rpcRequest{{service: elems[0], method: elems[1], id: &in.Id}}, false, nil
 	}
 
-	return []rpcRequest{rpcRequest{service: elems[0], method: elems[1], id: &in.Id, params: in.Payload}}, false, nil
+	return []rpcRequest{{service: elems[0], method: elems[1], id: &in.Id, params: in.Payload}}, false, nil
 }
 
 // parseBatchRequest will parse a batch request into a collection of requests from the given RawMessage, an indication
diff --git a/swarm/network/protocol.go b/swarm/network/protocol.go
index 4fffaac6d..763fb0b8e 100644
--- a/swarm/network/protocol.go
+++ b/swarm/network/protocol.go
@@ -538,13 +538,6 @@ func (self *bzz) protoError(code int, format string, params ...interface{}) (err
 	return
 }
 
-func (self *bzz) protoErrorDisconnect(err *errs.Error) {
-	err.Log(glog.V(logger.Info))
-	if err.Fatal() {
-		self.peer.Disconnect(p2p.DiscSubprotocolError)
-	}
-}
-
 func (self *bzz) send(msg uint64, data interface{}) error {
 	if self.hive.blockWrite {
 		return fmt.Errorf("network write blocked")
diff --git a/swarm/storage/dbstore.go b/swarm/storage/dbstore.go
index 5ecc5c500..4ddebb021 100644
--- a/swarm/storage/dbstore.go
+++ b/swarm/storage/dbstore.go
@@ -354,7 +354,7 @@ func (s *DbStore) Get(key Key) (chunk *Chunk, err error) {
 		hasher := s.hashfunc()
 		hasher.Write(data)
 		hash := hasher.Sum(nil)
-		if bytes.Compare(hash, key) != 0 {
+		if !bytes.Equal(hash, key) {
 			s.db.Delete(getDataKey(index.Idx))
 			err = fmt.Errorf("invalid chunk. hash=%x, key=%v", hash, key[:])
 			return
diff --git a/swarm/storage/dpa_test.go b/swarm/storage/dpa_test.go
index 1cde1c00e..a68232407 100644
--- a/swarm/storage/dpa_test.go
+++ b/swarm/storage/dpa_test.go
@@ -67,7 +67,7 @@ func TestDPArandom(t *testing.T) {
 	ioutil.WriteFile("/tmp/result.bzz.16M", resultSlice, 0666)
 	localStore.memStore = NewMemStore(dbStore, defaultCacheCapacity)
 	resultReader = dpa.Retrieve(key)
-	for i, _ := range resultSlice {
+	for i := range resultSlice {
 		resultSlice[i] = 0
 	}
 	n, err = resultReader.ReadAt(resultSlice, 0)
@@ -128,7 +128,7 @@ func TestDPA_capacity(t *testing.T) {
 	dpa.ChunkStore = localStore
 	//	localStore.dbStore.setCapacity(0)
 	resultReader = dpa.Retrieve(key)
-	for i, _ := range resultSlice {
+	for i := range resultSlice {
 		resultSlice[i] = 0
 	}
 	n, err = resultReader.ReadAt(resultSlice, 0)
diff --git a/swarm/storage/types.go b/swarm/storage/types.go
index 0dcbc0100..c36522012 100644
--- a/swarm/storage/types.go
+++ b/swarm/storage/types.go
@@ -41,7 +41,7 @@ func (x Key) Size() uint {
 }
 
 func (x Key) isEqual(y Key) bool {
-	return bytes.Compare(x, y) == 0
+	return bytes.Equal(x, y)
 }
 
 func (h Key) bits(i, j uint) uint {
diff --git a/tests/block_test_util.go b/tests/block_test_util.go
index f04329546..ea63c9996 100644
--- a/tests/block_test_util.go
+++ b/tests/block_test_util.go
@@ -552,9 +552,7 @@ func LoadBlockTests(file string) (map[string]*BlockTest, error) {
 // Nothing to see here, please move along...
 func prepInt(base int, s string) string {
 	if base == 16 {
-		if strings.HasPrefix(s, "0x") {
-			s = s[2:]
-		}
+		s = strings.TrimPrefix(s, "0x")
 		if len(s) == 0 {
 			s = "00"
 		}
diff --git a/tests/init.go b/tests/init.go
index 361be5f62..7b0924bc3 100644
--- a/tests/init.go
+++ b/tests/init.go
@@ -87,11 +87,7 @@ func readJsonHttp(uri string, value interface{}) error {
 	}
 	defer resp.Body.Close()
 
-	err = readJson(resp.Body, value)
-	if err != nil {
-		return err
-	}
-	return nil
+	return readJson(resp.Body, value)
 }
 
 func readJsonFile(fn string, value interface{}) error {
diff --git a/tests/state_test_util.go b/tests/state_test_util.go
index 8221815a8..7841aecfe 100644
--- a/tests/state_test_util.go
+++ b/tests/state_test_util.go
@@ -159,7 +159,7 @@ func runStateTest(chainConfig *params.ChainConfig, test VmTest) error {
 	} else {
 		rexp = common.FromHex(test.Out)
 	}
-	if bytes.Compare(rexp, ret) != 0 {
+	if !bytes.Equal(rexp, ret) {
 		return fmt.Errorf("return failed. Expected %x, got %x\n", rexp, ret)
 	}
 
diff --git a/tests/vm_test_util.go b/tests/vm_test_util.go
index d6411147f..f3b9fd1c9 100644
--- a/tests/vm_test_util.go
+++ b/tests/vm_test_util.go
@@ -172,7 +172,7 @@ func runVmTest(test VmTest) error {
 
 	// Compare expected and actual return
 	rexp := common.FromHex(test.Out)
-	if bytes.Compare(rexp, ret) != 0 {
+	if !bytes.Equal(rexp, ret) {
 		return fmt.Errorf("return failed. Expected %x, got %x\n", rexp, ret)
 	}
 
diff --git a/trie/encoding.go b/trie/encoding.go
index 761bad188..2037118dd 100644
--- a/trie/encoding.go
+++ b/trie/encoding.go
@@ -80,7 +80,7 @@ func compactHexEncode(nibbles []byte) []byte {
 	}
 	l := (nl + 1) / 2
 	var str = make([]byte, l)
-	for i, _ := range str {
+	for i := range str {
 		b := nibbles[i*2] * 16
 		if nl > i*2 {
 			b += nibbles[i*2+1]
diff --git a/trie/iterator_test.go b/trie/iterator_test.go
index 2bcc3700e..c56ac85be 100644
--- a/trie/iterator_test.go
+++ b/trie/iterator_test.go
@@ -105,7 +105,7 @@ func TestNodeIteratorCoverage(t *testing.T) {
 		}
 	}
 	// Cross check the hashes and the database itself
-	for hash, _ := range hashes {
+	for hash := range hashes {
 		if _, err := db.Get(hash.Bytes()); err != nil {
 			t.Errorf("failed to retrieve reported node %x: %v", hash, err)
 		}
diff --git a/trie/sync_test.go b/trie/sync_test.go
index 5edbd0746..4168c4d65 100644
--- a/trie/sync_test.go
+++ b/trie/sync_test.go
@@ -67,7 +67,7 @@ func checkTrieContents(t *testing.T, db Database, root []byte, content map[strin
 		t.Fatalf("inconsistent trie at %x: %v", root, err)
 	}
 	for key, val := range content {
-		if have := trie.Get([]byte(key)); bytes.Compare(have, val) != 0 {
+		if have := trie.Get([]byte(key)); !bytes.Equal(have, val) {
 			t.Errorf("entry %x: content mismatch: have %x, want %x", key, have, val)
 		}
 	}
@@ -182,7 +182,7 @@ func testIterativeRandomTrieSync(t *testing.T, batch int) {
 	for len(queue) > 0 {
 		// Fetch all the queued nodes in a random order
 		results := make([]SyncResult, 0, len(queue))
-		for hash, _ := range queue {
+		for hash := range queue {
 			data, err := srcDb.Get(hash.Bytes())
 			if err != nil {
 				t.Fatalf("failed to retrieve node data for %x: %v", hash, err)
@@ -219,7 +219,7 @@ func TestIterativeRandomDelayedTrieSync(t *testing.T) {
 	for len(queue) > 0 {
 		// Sync only half of the scheduled nodes, even those in random order
 		results := make([]SyncResult, 0, len(queue)/2+1)
-		for hash, _ := range queue {
+		for hash := range queue {
 			data, err := srcDb.Get(hash.Bytes())
 			if err != nil {
 				t.Fatalf("failed to retrieve node data for %x: %v", hash, err)
diff --git a/whisper/shhapi/api.go b/whisper/shhapi/api.go
index 24d54b653..379bb90d3 100644
--- a/whisper/shhapi/api.go
+++ b/whisper/shhapi/api.go
@@ -178,14 +178,10 @@ func (api *PublicWhisperAPI) NewFilter(args WhisperFilterArgs) (uint32, error) {
 		Messages:  make(map[common.Hash]*whisperv5.ReceivedMessage),
 		AcceptP2P: args.AcceptP2P,
 	}
-
 	if len(filter.KeySym) > 0 {
 		filter.SymKeyHash = crypto.Keccak256Hash(filter.KeySym)
 	}
-
-	for _, t := range args.Topics {
-		filter.Topics = append(filter.Topics, t)
-	}
+	filter.Topics = append(filter.Topics, args.Topics...)
 
 	if len(args.Topics) == 0 {
 		info := "NewFilter: at least one topic must be specified"
diff --git a/whisper/shhapi/api_test.go b/whisper/shhapi/api_test.go
index d2890a9a3..60b6fbd04 100644
--- a/whisper/shhapi/api_test.go
+++ b/whisper/shhapi/api_test.go
@@ -253,7 +253,7 @@ func TestUnmarshalPostArgs(t *testing.T) {
 	if a.FilterID != 64 {
 		t.Fatalf("wrong FilterID: %d.", a.FilterID)
 	}
-	if bytes.Compare(a.PeerID[:], a.Topic[:]) != 0 {
+	if !bytes.Equal(a.PeerID[:], a.Topic[:]) {
 		t.Fatalf("wrong PeerID: %x.", a.PeerID)
 	}
 }
diff --git a/whisper/whisperv2/envelope_test.go b/whisper/whisperv2/envelope_test.go
index 75e2fbe8a..c1b128c61 100644
--- a/whisper/whisperv2/envelope_test.go
+++ b/whisper/whisperv2/envelope_test.go
@@ -40,10 +40,10 @@ func TestEnvelopeOpen(t *testing.T) {
 	if opened.Flags != message.Flags {
 		t.Fatalf("flags mismatch: have %d, want %d", opened.Flags, message.Flags)
 	}
-	if bytes.Compare(opened.Signature, message.Signature) != 0 {
+	if !bytes.Equal(opened.Signature, message.Signature) {
 		t.Fatalf("signature mismatch: have 0x%x, want 0x%x", opened.Signature, message.Signature)
 	}
-	if bytes.Compare(opened.Payload, message.Payload) != 0 {
+	if !bytes.Equal(opened.Payload, message.Payload) {
 		t.Fatalf("payload mismatch: have 0x%x, want 0x%x", opened.Payload, message.Payload)
 	}
 	if opened.Sent.Unix() != message.Sent.Unix() {
@@ -71,7 +71,7 @@ func TestEnvelopeAnonymousOpenUntargeted(t *testing.T) {
 	if opened.To != nil {
 		t.Fatalf("recipient mismatch: have 0x%x, want nil", opened.To)
 	}
-	if bytes.Compare(opened.Payload, payload) != 0 {
+	if !bytes.Equal(opened.Payload, payload) {
 		t.Fatalf("payload mismatch: have 0x%x, want 0x%x", opened.Payload, payload)
 	}
 }
@@ -96,7 +96,7 @@ func TestEnvelopeAnonymousOpenTargeted(t *testing.T) {
 	if opened.To != nil {
 		t.Fatalf("recipient mismatch: have 0x%x, want nil", opened.To)
 	}
-	if bytes.Compare(opened.Payload, payload) == 0 {
+	if bytes.Equal(opened.Payload, payload) {
 		t.Fatalf("payload match, should have been encrypted: 0x%x", opened.Payload)
 	}
 }
@@ -127,7 +127,7 @@ func TestEnvelopeIdentifiedOpenUntargeted(t *testing.T) {
 	if opened.To != nil {
 		t.Fatalf("recipient mismatch: have 0x%x, want nil", opened.To)
 	}
-	if bytes.Compare(opened.Payload, payload) != 0 {
+	if !bytes.Equal(opened.Payload, payload) {
 		t.Fatalf("payload mismatch: have 0x%x, want 0x%x", opened.Payload, payload)
 	}
 }
@@ -152,7 +152,7 @@ func TestEnvelopeIdentifiedOpenTargeted(t *testing.T) {
 	if opened.To != nil {
 		t.Fatalf("recipient mismatch: have 0x%x, want nil", opened.To)
 	}
-	if bytes.Compare(opened.Payload, payload) != 0 {
+	if !bytes.Equal(opened.Payload, payload) {
 		t.Fatalf("payload mismatch: have 0x%x, want 0x%x", opened.Payload, payload)
 	}
 }
diff --git a/whisper/whisperv2/filter.go b/whisper/whisperv2/filter.go
index 8ce4a54fb..7404859b7 100644
--- a/whisper/whisperv2/filter.go
+++ b/whisper/whisperv2/filter.go
@@ -116,14 +116,11 @@ func (self filterer) Compare(f filter.Filter) bool {
 	topics := make([]Topic, len(filter.matcher.conditions))
 	for i, group := range filter.matcher.conditions {
 		// Message should contain a single topic entry, extract
-		for topics[i], _ = range group {
+		for topics[i] = range group {
 			break
 		}
 	}
-	if !self.matcher.Matches(topics) {
-		return false
-	}
-	return true
+	return self.matcher.Matches(topics)
 }
 
 // Trigger is called when a filter successfully matches an inbound message.
diff --git a/whisper/whisperv2/filter_test.go b/whisper/whisperv2/filter_test.go
index 5a14a84bb..ffdfd7b34 100644
--- a/whisper/whisperv2/filter_test.go
+++ b/whisper/whisperv2/filter_test.go
@@ -91,7 +91,7 @@ func TestFilterTopicsCreation(t *testing.T) {
 				continue
 			}
 			for k := 0; k < len(condition); k++ {
-				if bytes.Compare(condition[k][:], tt.filter[j][k][:]) != 0 {
+				if !bytes.Equal(condition[k][:], tt.filter[j][k][:]) {
 					t.Errorf("test %d, condition %d, segment %d: filter mismatch: have 0x%x, want 0x%x", i, j, k, condition[k], tt.filter[j][k])
 				}
 			}
@@ -115,7 +115,7 @@ func TestFilterTopicsCreation(t *testing.T) {
 				continue
 			}
 			for k := 0; k < len(condition); k++ {
-				if bytes.Compare(condition[k][:], tt.filter[j][k][:]) != 0 {
+				if !bytes.Equal(condition[k][:], tt.filter[j][k][:]) {
 					t.Errorf("test %d, condition %d, segment %d: filter mismatch: have 0x%x, want 0x%x", i, j, k, condition[k], tt.filter[j][k])
 				}
 			}
@@ -135,7 +135,7 @@ func TestFilterTopicsCreation(t *testing.T) {
 				continue
 			}
 			for k := 0; k < len(condition); k++ {
-				if bytes.Compare(condition[k][:], tt.filter[j][k][:]) != 0 {
+				if !bytes.Equal(condition[k][:], tt.filter[j][k][:]) {
 					t.Errorf("test %d, condition %d, segment %d: filter mismatch: have 0x%x, want 0x%x", i, j, k, condition[k], tt.filter[j][k])
 				}
 			}
@@ -156,7 +156,7 @@ func TestFilterTopicsCreation(t *testing.T) {
 				continue
 			}
 			for k := 0; k < len(condition); k++ {
-				if bytes.Compare(condition[k][:], tt.filter[j][k][:]) != 0 {
+				if !bytes.Equal(condition[k][:], tt.filter[j][k][:]) {
 					t.Errorf("test %d, condition %d, segment %d: filter mismatch: have 0x%x, want 0x%x", i, j, k, condition[k], tt.filter[j][k])
 				}
 			}
diff --git a/whisper/whisperv2/message_test.go b/whisper/whisperv2/message_test.go
index efa64e431..d3b307d2a 100644
--- a/whisper/whisperv2/message_test.go
+++ b/whisper/whisperv2/message_test.go
@@ -40,7 +40,7 @@ func TestMessageSimpleWrap(t *testing.T) {
 	if len(msg.Signature) != 0 {
 		t.Fatalf("signature found for simple wrapping: 0x%x", msg.Signature)
 	}
-	if bytes.Compare(msg.Payload, payload) != 0 {
+	if !bytes.Equal(msg.Payload, payload) {
 		t.Fatalf("payload mismatch after wrapping: have 0x%x, want 0x%x", msg.Payload, payload)
 	}
 	if msg.TTL/time.Second != DefaultTTL/time.Second {
@@ -65,7 +65,7 @@ func TestMessageCleartextSignRecover(t *testing.T) {
 	if msg.Flags&signatureFlag != signatureFlag {
 		t.Fatalf("signature flag mismatch: have %d, want %d", msg.Flags&signatureFlag, signatureFlag)
 	}
-	if bytes.Compare(msg.Payload, payload) != 0 {
+	if !bytes.Equal(msg.Payload, payload) {
 		t.Fatalf("payload mismatch after signing: have 0x%x, want 0x%x", msg.Payload, payload)
 	}
 
diff --git a/whisper/whisperv2/peer.go b/whisper/whisperv2/peer.go
index 404ebd513..f09ce3523 100644
--- a/whisper/whisperv2/peer.go
+++ b/whisper/whisperv2/peer.go
@@ -149,7 +149,7 @@ func (self *peer) expire() {
 		return true
 	})
 	// Dump all known but unavailable
-	for hash, _ := range unmark {
+	for hash := range unmark {
 		self.known.Remove(hash)
 	}
 }
diff --git a/whisper/whisperv2/peer_test.go b/whisper/whisperv2/peer_test.go
index 9755e134c..87ca5063d 100644
--- a/whisper/whisperv2/peer_test.go
+++ b/whisper/whisperv2/peer_test.go
@@ -221,7 +221,7 @@ func TestPeerMessageExpiration(t *testing.T) {
 		t.Fatalf("peer pool size mismatch: have %v, want %v", peers, 1)
 	}
 	var peer *peer
-	for peer, _ = range tester.client.peers {
+	for peer = range tester.client.peers {
 		break
 	}
 	tester.client.peerMu.RUnlock()
diff --git a/whisper/whisperv2/topic_test.go b/whisper/whisperv2/topic_test.go
index efd4a2c61..bb6568996 100644
--- a/whisper/whisperv2/topic_test.go
+++ b/whisper/whisperv2/topic_test.go
@@ -33,13 +33,13 @@ func TestTopicCreation(t *testing.T) {
 	// Create the topics individually
 	for i, tt := range topicCreationTests {
 		topic := NewTopic(tt.data)
-		if bytes.Compare(topic[:], tt.hash[:]) != 0 {
+		if !bytes.Equal(topic[:], tt.hash[:]) {
 			t.Errorf("binary test %d: hash mismatch: have %v, want %v.", i, topic, tt.hash)
 		}
 	}
 	for i, tt := range topicCreationTests {
 		topic := NewTopicFromString(string(tt.data))
-		if bytes.Compare(topic[:], tt.hash[:]) != 0 {
+		if !bytes.Equal(topic[:], tt.hash[:]) {
 			t.Errorf("textual test %d: hash mismatch: have %v, want %v.", i, topic, tt.hash)
 		}
 	}
@@ -55,13 +55,13 @@ func TestTopicCreation(t *testing.T) {
 
 	topics := NewTopics(binaryData...)
 	for i, tt := range topicCreationTests {
-		if bytes.Compare(topics[i][:], tt.hash[:]) != 0 {
+		if !bytes.Equal(topics[i][:], tt.hash[:]) {
 			t.Errorf("binary batch test %d: hash mismatch: have %v, want %v.", i, topics[i], tt.hash)
 		}
 	}
 	topics = NewTopicsFromStrings(textualData...)
 	for i, tt := range topicCreationTests {
-		if bytes.Compare(topics[i][:], tt.hash[:]) != 0 {
+		if !bytes.Equal(topics[i][:], tt.hash[:]) {
 			t.Errorf("textual batch test %d: hash mismatch: have %v, want %v.", i, topics[i], tt.hash)
 		}
 	}
@@ -73,30 +73,30 @@ var topicMatcherCreationTest = struct {
 	matcher []map[[4]byte]struct{}
 }{
 	binary: [][][]byte{
-		[][]byte{},
-		[][]byte{
+		{},
+		{
 			[]byte("Topic A"),
 		},
-		[][]byte{
+		{
 			[]byte("Topic B1"),
 			[]byte("Topic B2"),
 			[]byte("Topic B3"),
 		},
 	},
 	textual: [][]string{
-		[]string{},
-		[]string{"Topic A"},
-		[]string{"Topic B1", "Topic B2", "Topic B3"},
+		{},
+		{"Topic A"},
+		{"Topic B1", "Topic B2", "Topic B3"},
 	},
 	matcher: []map[[4]byte]struct{}{
-		map[[4]byte]struct{}{},
-		map[[4]byte]struct{}{
-			[4]byte{0x25, 0xfc, 0x95, 0x66}: struct{}{},
+		{},
+		{
+			{0x25, 0xfc, 0x95, 0x66}: {},
 		},
-		map[[4]byte]struct{}{
-			[4]byte{0x93, 0x6d, 0xec, 0x09}: struct{}{},
-			[4]byte{0x25, 0x23, 0x34, 0xd3}: struct{}{},
-			[4]byte{0x6b, 0xc2, 0x73, 0xd1}: struct{}{},
+		{
+			{0x93, 0x6d, 0xec, 0x09}: {},
+			{0x25, 0x23, 0x34, 0xd3}: {},
+			{0x6b, 0xc2, 0x73, 0xd1}: {},
 		},
 	},
 }
@@ -106,14 +106,14 @@ func TestTopicMatcherCreation(t *testing.T) {
 
 	matcher := newTopicMatcherFromBinary(test.binary...)
 	for i, cond := range matcher.conditions {
-		for topic, _ := range cond {
+		for topic := range cond {
 			if _, ok := test.matcher[i][topic]; !ok {
 				t.Errorf("condition %d; extra topic found: 0x%x", i, topic[:])
 			}
 		}
 	}
 	for i, cond := range test.matcher {
-		for topic, _ := range cond {
+		for topic := range cond {
 			if _, ok := matcher.conditions[i][topic]; !ok {
 				t.Errorf("condition %d; topic not found: 0x%x", i, topic[:])
 			}
@@ -122,14 +122,14 @@ func TestTopicMatcherCreation(t *testing.T) {
 
 	matcher = newTopicMatcherFromStrings(test.textual...)
 	for i, cond := range matcher.conditions {
-		for topic, _ := range cond {
+		for topic := range cond {
 			if _, ok := test.matcher[i][topic]; !ok {
 				t.Errorf("condition %d; extra topic found: 0x%x", i, topic[:])
 			}
 		}
 	}
 	for i, cond := range test.matcher {
-		for topic, _ := range cond {
+		for topic := range cond {
 			if _, ok := matcher.conditions[i][topic]; !ok {
 				t.Errorf("condition %d; topic not found: 0x%x", i, topic[:])
 			}
@@ -155,49 +155,49 @@ var topicMatcherTests = []struct {
 	},
 	// Fixed topic matcher should match strictly, but only prefix
 	{
-		filter: [][]string{[]string{"a"}, []string{"b"}},
+		filter: [][]string{{"a"}, {"b"}},
 		topics: []string{"a"},
 		match:  false,
 	},
 	{
-		filter: [][]string{[]string{"a"}, []string{"b"}},
+		filter: [][]string{{"a"}, {"b"}},
 		topics: []string{"a", "b"},
 		match:  true,
 	},
 	{
-		filter: [][]string{[]string{"a"}, []string{"b"}},
+		filter: [][]string{{"a"}, {"b"}},
 		topics: []string{"a", "b", "c"},
 		match:  true,
 	},
 	// Multi-matcher should match any from a sub-group
 	{
-		filter: [][]string{[]string{"a1", "a2"}},
+		filter: [][]string{{"a1", "a2"}},
 		topics: []string{"a"},
 		match:  false,
 	},
 	{
-		filter: [][]string{[]string{"a1", "a2"}},
+		filter: [][]string{{"a1", "a2"}},
 		topics: []string{"a1"},
 		match:  true,
 	},
 	{
-		filter: [][]string{[]string{"a1", "a2"}},
+		filter: [][]string{{"a1", "a2"}},
 		topics: []string{"a2"},
 		match:  true,
 	},
 	// Wild-card condition should match anything
 	{
-		filter: [][]string{[]string{}, []string{"b"}},
+		filter: [][]string{{}, {"b"}},
 		topics: []string{"a"},
 		match:  false,
 	},
 	{
-		filter: [][]string{[]string{}, []string{"b"}},
+		filter: [][]string{{}, {"b"}},
 		topics: []string{"a", "b"},
 		match:  true,
 	},
 	{
-		filter: [][]string{[]string{}, []string{"b"}},
+		filter: [][]string{{}, {"b"}},
 		topics: []string{"b", "b"},
 		match:  true,
 	},
diff --git a/whisper/whisperv5/message_test.go b/whisper/whisperv5/message_test.go
index 5cbc9182f..3eb71653d 100644
--- a/whisper/whisperv5/message_test.go
+++ b/whisper/whisperv5/message_test.go
@@ -104,10 +104,10 @@ func singleMessageTest(t *testing.T, symmetric bool) {
 	}
 
 	padsz := len(decrypted.Padding)
-	if bytes.Compare(steg[:padsz], decrypted.Padding) != 0 {
+	if !bytes.Equal(steg[:padsz], decrypted.Padding) {
 		t.Fatalf("failed with seed %d: compare padding.", seed)
 	}
-	if bytes.Compare(text, decrypted.Payload) != 0 {
+	if !bytes.Equal(text, decrypted.Payload) {
 		t.Fatalf("failed with seed %d: compare payload.", seed)
 	}
 	if !isMessageSigned(decrypted.Raw[0]) {
@@ -256,10 +256,10 @@ func singleEnvelopeOpenTest(t *testing.T, symmetric bool) {
 	}
 
 	padsz := len(decrypted.Padding)
-	if bytes.Compare(steg[:padsz], decrypted.Padding) != 0 {
+	if !bytes.Equal(steg[:padsz], decrypted.Padding) {
 		t.Fatalf("failed with seed %d: compare padding.", seed)
 	}
-	if bytes.Compare(text, decrypted.Payload) != 0 {
+	if !bytes.Equal(text, decrypted.Payload) {
 		t.Fatalf("failed with seed %d: compare payload.", seed)
 	}
 	if !isMessageSigned(decrypted.Raw[0]) {
diff --git a/whisper/whisperv5/peer.go b/whisper/whisperv5/peer.go
index 4273cfce1..634045504 100644
--- a/whisper/whisperv5/peer.go
+++ b/whisper/whisperv5/peer.go
@@ -148,7 +148,7 @@ func (peer *Peer) expire() {
 		return true
 	})
 	// Dump all known but unavailable
-	for hash, _ := range unmark {
+	for hash := range unmark {
 		peer.known.Remove(hash)
 	}
 }
diff --git a/whisper/whisperv5/peer_test.go b/whisper/whisperv5/peer_test.go
index 88da59bff..34e2ec255 100644
--- a/whisper/whisperv5/peer_test.go
+++ b/whisper/whisperv5/peer_test.go
@@ -207,7 +207,7 @@ func checkPropagation(t *testing.T) {
 func validateMail(t *testing.T, index int, mail []*ReceivedMessage) bool {
 	var cnt int
 	for _, m := range mail {
-		if bytes.Compare(m.Payload, expectedMessage) == 0 {
+		if bytes.Equal(m.Payload, expectedMessage) {
 			cnt++
 		}
 	}
diff --git a/whisper/whisperv5/whisper.go b/whisper/whisperv5/whisper.go
index 789adbdb3..b514c022e 100644
--- a/whisper/whisperv5/whisper.go
+++ b/whisper/whisperv5/whisper.go
@@ -105,7 +105,7 @@ func (w *Whisper) Version() uint {
 func (w *Whisper) getPeer(peerID []byte) (*Peer, error) {
 	w.peerMu.Lock()
 	defer w.peerMu.Unlock()
-	for p, _ := range w.peers {
+	for p := range w.peers {
 		id := p.peer.ID()
 		if bytes.Equal(peerID, id[:]) {
 			return p, nil
diff --git a/whisper/whisperv5/whisper_test.go b/whisper/whisperv5/whisper_test.go
index 9af95f445..dbe0627fa 100644
--- a/whisper/whisperv5/whisper_test.go
+++ b/whisper/whisperv5/whisper_test.go
@@ -239,7 +239,7 @@ func TestWhisperSymKeyManagement(t *testing.T) {
 	if k1 == nil {
 		t.Fatalf("first key does not exist.")
 	}
-	if bytes.Compare(k1, randomKey) == 0 {
+	if bytes.Equal(k1, randomKey) {
 		t.Fatalf("k1 == randomKey.")
 	}
 	if k2 != nil {
@@ -264,10 +264,10 @@ func TestWhisperSymKeyManagement(t *testing.T) {
 	if k2 == nil {
 		t.Fatalf("k2 does not exist.")
 	}
-	if bytes.Compare(k1, k2) == 0 {
+	if bytes.Equal(k1, k2) {
 		t.Fatalf("k1 == k2.")
 	}
-	if bytes.Compare(k1, randomKey) == 0 {
+	if bytes.Equal(k1, randomKey) {
 		t.Fatalf("k1 == randomKey.")
 	}
 	if len(k1) != aesKeyLength {