Merge pull request #2930 from fjl/ethclient

Stable Go API, part 1

25 files changed, 1716 insertions, 558 deletions

diff --git a/accounts/abi/bind/backend.go b/accounts/abi/bind/backend.go
index bec742c29..a4e90914f 100644
--- a/accounts/abi/bind/backend.go
+++ b/accounts/abi/bind/backend.go
@@ -20,28 +20,52 @@ import (
 	"errors"
 	"math/big"
 
+	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"golang.org/x/net/context"
 )
 
-// ErrNoCode is returned by call and transact operations for which the requested
-// recipient contract to operate on does not exist in the state db or does not
-// have any code associated with it (i.e. suicided).
-var ErrNoCode = errors.New("no contract code at given address")
+var (
+	// ErrNoCode is returned by call and transact operations for which the requested
+	// recipient contract to operate on does not exist in the state db or does not
+	// have any code associated with it (i.e. suicided).
+	ErrNoCode = errors.New("no contract code at given address")
+
+	// This error is raised when attempting to perform a pending state action
+	// on a backend that doesn't implement PendingContractCaller.
+	ErrNoPendingState = errors.New("backend does not support pending state")
+
+	// This error is returned by WaitDeployed if contract creation leaves an
+	// empty contract behind.
+	ErrNoCodeAfterDeploy = errors.New("no contract code after deployment")
+)
 
 // ContractCaller defines the methods needed to allow operating with contract on a read
 // only basis.
 type ContractCaller interface {
-	// HasCode checks if the contract at the given address has any code associated
-	// with it or not. This is needed to differentiate between contract internal
-	// errors and the local chain being out of sync.
-	HasCode(ctx context.Context, contract common.Address, pending bool) (bool, error)
+	// CodeAt returns the code of the given account. This is needed to differentiate
+	// between contract internal errors and the local chain being out of sync.
+	CodeAt(ctx context.Context, contract common.Address, blockNumber *big.Int) ([]byte, error)
+	// ContractCall executes an Ethereum contract call with the specified data as the
+	// input.
+	CallContract(ctx context.Context, call ethereum.CallMsg, blockNumber *big.Int) ([]byte, error)
+}
 
-	// ContractCall executes an Ethereum contract call with the specified data as
-	// the input. The pending flag requests execution against the pending block, not
-	// the stable head of the chain.
-	ContractCall(ctx context.Context, contract common.Address, data []byte, pending bool) ([]byte, error)
+// DeployBackend wraps the operations needed by WaitMined and WaitDeployed.
+type DeployBackend interface {
+	TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error)
+	CodeAt(ctx context.Context, account common.Address, blockNumber *big.Int) ([]byte, error)
+}
+
+// PendingContractCaller defines methods to perform contract calls on the pending state.
+// Call will try to discover this interface when access to the pending state is requested.
+// If the backend does not support the pending state, Call returns ErrNoPendingState.
+type PendingContractCaller interface {
+	// PendingCodeAt returns the code of the given account in the pending state.
+	PendingCodeAt(ctx context.Context, contract common.Address) ([]byte, error)
+	// PendingCallContract executes an Ethereum contract call against the pending state.
+	PendingCallContract(ctx context.Context, call ethereum.CallMsg) ([]byte, error)
 }
 
 // ContractTransactor defines the methods needed to allow operating with contract
@@ -49,64 +73,25 @@ type ContractCaller interface {
 // used when the user does not provide some needed values, but rather leaves it up
 // to the transactor to decide.
 type ContractTransactor interface {
-	// PendingAccountNonce retrieves the current pending nonce associated with an
-	// account.
-	PendingAccountNonce(ctx context.Context, account common.Address) (uint64, error)
-
+	// PendingCodeAt returns the code of the given account in the pending state.
+	PendingCodeAt(ctx context.Context, account common.Address) ([]byte, error)
+	// PendingNonceAt retrieves the current pending nonce associated with an account.
+	PendingNonceAt(ctx context.Context, account common.Address) (uint64, error)
 	// SuggestGasPrice retrieves the currently suggested gas price to allow a timely
 	// execution of a transaction.
 	SuggestGasPrice(ctx context.Context) (*big.Int, error)
-
-	// HasCode checks if the contract at the given address has any code associated
-	// with it or not. This is needed to differentiate between contract internal
-	// errors and the local chain being out of sync.
-	HasCode(ctx context.Context, contract common.Address, pending bool) (bool, error)
-
-	// EstimateGasLimit tries to estimate the gas needed to execute a specific
+	// EstimateGas tries to estimate the gas needed to execute a specific
 	// transaction based on the current pending state of the backend blockchain.
 	// There is no guarantee that this is the true gas limit requirement as other
 	// transactions may be added or removed by miners, but it should provide a basis
 	// for setting a reasonable default.
-	EstimateGasLimit(ctx context.Context, sender common.Address, contract *common.Address, value *big.Int, data []byte) (*big.Int, error)
-
+	EstimateGas(ctx context.Context, call ethereum.CallMsg) (usedGas *big.Int, err error)
 	// SendTransaction injects the transaction into the pending pool for execution.
 	SendTransaction(ctx context.Context, tx *types.Transaction) error
 }
 
-// ContractBackend defines the methods needed to allow operating with contract
-// on a read-write basis.
-//
-// This interface is essentially the union of ContractCaller and ContractTransactor
-// but due to a bug in the Go compiler (https://github.com/golang/go/issues/6977),
-// we cannot simply list it as the two interfaces. The other solution is to add a
-// third interface containing the common methods, but that convolutes the user API
-// as it introduces yet another parameter to require for initialization.
+// ContractBackend defines the methods needed to work with contracts on a read-write basis.
 type ContractBackend interface {
-	// HasCode checks if the contract at the given address has any code associated
-	// with it or not. This is needed to differentiate between contract internal
-	// errors and the local chain being out of sync.
-	HasCode(ctx context.Context, contract common.Address, pending bool) (bool, error)
-
-	// ContractCall executes an Ethereum contract call with the specified data as
-	// the input. The pending flag requests execution against the pending block, not
-	// the stable head of the chain.
-	ContractCall(ctx context.Context, contract common.Address, data []byte, pending bool) ([]byte, error)
-
-	// PendingAccountNonce retrieves the current pending nonce associated with an
-	// account.
-	PendingAccountNonce(ctx context.Context, account common.Address) (uint64, error)
-
-	// SuggestGasPrice retrieves the currently suggested gas price to allow a timely
-	// execution of a transaction.
-	SuggestGasPrice(ctx context.Context) (*big.Int, error)
-
-	// EstimateGasLimit tries to estimate the gas needed to execute a specific
-	// transaction based on the current pending state of the backend blockchain.
-	// There is no guarantee that this is the true gas limit requirement as other
-	// transactions may be added or removed by miners, but it should provide a basis
-	// for setting a reasonable default.
-	EstimateGasLimit(ctx context.Context, sender common.Address, contract *common.Address, value *big.Int, data []byte) (*big.Int, error)
-
-	// SendTransaction injects the transaction into the pending pool for execution.
-	SendTransaction(ctx context.Context, tx *types.Transaction) error
+	ContractCaller
+	ContractTransactor
 }
diff --git a/accounts/abi/bind/backends/nil.go b/accounts/abi/bind/backends/nil.go
deleted file mode 100644
index 54b222f1f..000000000
--- a/accounts/abi/bind/backends/nil.go
+++ /dev/null
@@ -1,57 +0,0 @@
-// Copyright 2016 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 backends
-
-import (
-	"math/big"
-
-	"github.com/ethereum/go-ethereum/accounts/abi/bind"
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/types"
-	"golang.org/x/net/context"
-)
-
-// This nil assignment ensures compile time that nilBackend implements bind.ContractBackend.
-var _ bind.ContractBackend = (*nilBackend)(nil)
-
-// nilBackend implements bind.ContractBackend, but panics on any method call.
-// Its sole purpose is to support the binding tests to construct the generated
-// wrappers without calling any methods on them.
-type nilBackend struct{}
-
-func (*nilBackend) ContractCall(context.Context, common.Address, []byte, bool) ([]byte, error) {
-	panic("not implemented")
-}
-func (*nilBackend) EstimateGasLimit(context.Context, common.Address, *common.Address, *big.Int, []byte) (*big.Int, error) {
-	panic("not implemented")
-}
-func (*nilBackend) HasCode(context.Context, common.Address, bool) (bool, error) {
-	panic("not implemented")
-}
-func (*nilBackend) SuggestGasPrice(context.Context) (*big.Int, error) { panic("not implemented") }
-func (*nilBackend) PendingAccountNonce(context.Context, common.Address) (uint64, error) {
-	panic("not implemented")
-}
-func (*nilBackend) SendTransaction(context.Context, *types.Transaction) error {
-	panic("not implemented")
-}
-
-// NewNilBackend creates a new binding backend that can be used for instantiation
-// but will panic on any invocation. Its sole purpose is to help testing.
-func NewNilBackend() bind.ContractBackend {
-	return new(nilBackend)
-}
diff --git a/accounts/abi/bind/backends/remote.go b/accounts/abi/bind/backends/remote.go
deleted file mode 100644
index 58edd791a..000000000
--- a/accounts/abi/bind/backends/remote.go
+++ /dev/null
@@ -1,136 +0,0 @@
-// Copyright 2016 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 backends
-
-import (
-	"math/big"
-
-	"github.com/ethereum/go-ethereum/accounts/abi/bind"
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/types"
-	"github.com/ethereum/go-ethereum/rlp"
-	"github.com/ethereum/go-ethereum/rpc"
-	"golang.org/x/net/context"
-)
-
-// This nil assignment ensures compile time that rpcBackend implements bind.ContractBackend.
-var _ bind.ContractBackend = (*rpcBackend)(nil)
-
-// rpcBackend implements bind.ContractBackend, and acts as the data provider to
-// Ethereum contracts bound to Go structs. It uses an RPC connection to delegate
-// all its functionality.
-type rpcBackend struct {
-	client *rpc.Client // RPC client connection to interact with an API server
-}
-
-// NewRPCBackend creates a new binding backend to an RPC provider that can be
-// used to interact with remote contracts.
-func NewRPCBackend(client *rpc.Client) bind.ContractBackend {
-	return &rpcBackend{client: client}
-}
-
-// HasCode implements ContractVerifier.HasCode by retrieving any code associated
-// with the contract from the remote node, and checking its size.
-func (b *rpcBackend) HasCode(ctx context.Context, contract common.Address, pending bool) (bool, error) {
-	block := "latest"
-	if pending {
-		block = "pending"
-	}
-	var hex string
-	err := b.client.CallContext(ctx, &hex, "eth_getCode", contract, block)
-	if err != nil {
-		return false, err
-	}
-	return len(common.FromHex(hex)) > 0, nil
-}
-
-// ContractCall implements ContractCaller.ContractCall, delegating the execution of
-// a contract call to the remote node, returning the reply to for local processing.
-func (b *rpcBackend) ContractCall(ctx context.Context, contract common.Address, data []byte, pending bool) ([]byte, error) {
-	args := struct {
-		To   common.Address `json:"to"`
-		Data string         `json:"data"`
-	}{
-		To:   contract,
-		Data: common.ToHex(data),
-	}
-	block := "latest"
-	if pending {
-		block = "pending"
-	}
-	var hex string
-	err := b.client.CallContext(ctx, &hex, "eth_call", args, block)
-	if err != nil {
-		return nil, err
-	}
-	return common.FromHex(hex), nil
-
-}
-
-// PendingAccountNonce implements ContractTransactor.PendingAccountNonce, delegating
-// the current account nonce retrieval to the remote node.
-func (b *rpcBackend) PendingAccountNonce(ctx context.Context, account common.Address) (uint64, error) {
-	var hex rpc.HexNumber
-	err := b.client.CallContext(ctx, &hex, "eth_getTransactionCount", account.Hex(), "pending")
-	if err != nil {
-		return 0, err
-	}
-	return hex.Uint64(), nil
-}
-
-// SuggestGasPrice implements ContractTransactor.SuggestGasPrice, delegating the
-// gas price oracle request to the remote node.
-func (b *rpcBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error) {
-	var hex rpc.HexNumber
-	if err := b.client.CallContext(ctx, &hex, "eth_gasPrice"); err != nil {
-		return nil, err
-	}
-	return (*big.Int)(&hex), nil
-}
-
-// EstimateGasLimit implements ContractTransactor.EstimateGasLimit, delegating
-// the gas estimation to the remote node.
-func (b *rpcBackend) EstimateGasLimit(ctx context.Context, sender common.Address, contract *common.Address, value *big.Int, data []byte) (*big.Int, error) {
-	args := struct {
-		From  common.Address  `json:"from"`
-		To    *common.Address `json:"to"`
-		Value *rpc.HexNumber  `json:"value"`
-		Data  string          `json:"data"`
-	}{
-		From:  sender,
-		To:    contract,
-		Data:  common.ToHex(data),
-		Value: rpc.NewHexNumber(value),
-	}
-	// Execute the RPC call and retrieve the response
-	var hex rpc.HexNumber
-	err := b.client.CallContext(ctx, &hex, "eth_estimateGas", args)
-	if err != nil {
-		return nil, err
-	}
-	return (*big.Int)(&hex), nil
-}
-
-// SendTransaction implements ContractTransactor.SendTransaction, delegating the
-// raw transaction injection to the remote node.
-func (b *rpcBackend) SendTransaction(ctx context.Context, tx *types.Transaction) error {
-	data, err := rlp.EncodeToBytes(tx)
-	if err != nil {
-		return err
-	}
-	return b.client.CallContext(ctx, nil, "eth_sendRawTransaction", common.ToHex(data))
-}
diff --git a/accounts/abi/bind/backends/simulated.go b/accounts/abi/bind/backends/simulated.go
index 687a31bf1..29b4e8ea3 100644
--- a/accounts/abi/bind/backends/simulated.go
+++ b/accounts/abi/bind/backends/simulated.go
@@ -17,8 +17,12 @@
 package backends
 
 import (
+	"errors"
+	"fmt"
 	"math/big"
+	"sync"
 
+	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/accounts/abi/bind"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
@@ -36,12 +40,15 @@ var chainConfig = &core.ChainConfig{HomesteadBlock: big.NewInt(0)}
 // This nil assignment ensures compile time that SimulatedBackend implements bind.ContractBackend.
 var _ bind.ContractBackend = (*SimulatedBackend)(nil)
 
+var errBlockNumberUnsupported = errors.New("SimulatedBackend cannot access blocks other than the latest block")
+
 // SimulatedBackend implements bind.ContractBackend, simulating a blockchain in
 // the background. Its main purpose is to allow easily testing contract bindings.
 type SimulatedBackend struct {
 	database   ethdb.Database   // In memory database to store our testing data
 	blockchain *core.BlockChain // Ethereum blockchain to handle the consensus
 
+	mu           sync.Mutex
 	pendingBlock *types.Block   // Currently pending block that will be imported on request
 	pendingState *state.StateDB // Currently pending state that will be the active on on request
 }
@@ -52,85 +59,133 @@ func NewSimulatedBackend(accounts ...core.GenesisAccount) *SimulatedBackend {
 	database, _ := ethdb.NewMemDatabase()
 	core.WriteGenesisBlockForTesting(database, accounts...)
 	blockchain, _ := core.NewBlockChain(database, chainConfig, new(core.FakePow), new(event.TypeMux))
-
-	backend := &SimulatedBackend{
-		database:   database,
-		blockchain: blockchain,
-	}
-	backend.Rollback()
-
+	backend := &SimulatedBackend{database: database, blockchain: blockchain}
+	backend.rollback()
 	return backend
 }
 
 // Commit imports all the pending transactions as a single block and starts a
 // fresh new state.
 func (b *SimulatedBackend) Commit() {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
 	if _, err := b.blockchain.InsertChain([]*types.Block{b.pendingBlock}); err != nil {
 		panic(err) // This cannot happen unless the simulator is wrong, fail in that case
 	}
-	b.Rollback()
+	b.rollback()
 }
 
 // Rollback aborts all pending transactions, reverting to the last committed state.
 func (b *SimulatedBackend) Rollback() {
-	blocks, _ := core.GenerateChain(nil, b.blockchain.CurrentBlock(), b.database, 1, func(int, *core.BlockGen) {})
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	b.rollback()
+}
 
+func (b *SimulatedBackend) rollback() {
+	blocks, _ := core.GenerateChain(nil, b.blockchain.CurrentBlock(), b.database, 1, func(int, *core.BlockGen) {})
 	b.pendingBlock = blocks[0]
 	b.pendingState, _ = state.New(b.pendingBlock.Root(), b.database)
 }
 
-// HasCode implements ContractVerifier.HasCode, checking whether there is any
-// code associated with a certain account in the blockchain.
-func (b *SimulatedBackend) HasCode(ctx context.Context, contract common.Address, pending bool) (bool, error) {
-	if pending {
-		return len(b.pendingState.GetCode(contract)) > 0, nil
+// CodeAt returns the code associated with a certain account in the blockchain.
+func (b *SimulatedBackend) CodeAt(ctx context.Context, contract common.Address, blockNumber *big.Int) ([]byte, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	if blockNumber != nil && blockNumber.Cmp(b.blockchain.CurrentBlock().Number()) != 0 {
+		return nil, errBlockNumberUnsupported
 	}
 	statedb, _ := b.blockchain.State()
-	return len(statedb.GetCode(contract)) > 0, nil
-}
-
-// ContractCall implements ContractCaller.ContractCall, executing the specified
-// contract with the given input data.
-func (b *SimulatedBackend) ContractCall(ctx context.Context, contract common.Address, data []byte, pending bool) ([]byte, error) {
-	// Create a copy of the current state db to screw around with
-	var (
-		block   *types.Block
-		statedb *state.StateDB
-	)
-	if pending {
-		block, statedb = b.pendingBlock, b.pendingState.Copy()
-	} else {
-		block = b.blockchain.CurrentBlock()
-		statedb, _ = b.blockchain.State()
+	return statedb.GetCode(contract), nil
+}
+
+// BalanceAt returns the wei balance of a certain account in the blockchain.
+func (b *SimulatedBackend) BalanceAt(ctx context.Context, contract common.Address, blockNumber *big.Int) (*big.Int, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	if blockNumber != nil && blockNumber.Cmp(b.blockchain.CurrentBlock().Number()) != 0 {
+		return nil, errBlockNumberUnsupported
 	}
-	// If there's no code to interact with, respond with an appropriate error
-	if code := statedb.GetCode(contract); len(code) == 0 {
-		return nil, bind.ErrNoCode
+	statedb, _ := b.blockchain.State()
+	return statedb.GetBalance(contract), nil
+}
+
+// NonceAt returns the nonce of a certain account in the blockchain.
+func (b *SimulatedBackend) NonceAt(ctx context.Context, contract common.Address, blockNumber *big.Int) (uint64, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	if blockNumber != nil && blockNumber.Cmp(b.blockchain.CurrentBlock().Number()) != 0 {
+		return 0, errBlockNumberUnsupported
 	}
-	// Set infinite balance to the a fake caller account
-	from := statedb.GetOrNewStateObject(common.Address{})
-	from.SetBalance(common.MaxBig)
+	statedb, _ := b.blockchain.State()
+	return statedb.GetNonce(contract), nil
+}
+
+// StorageAt returns the value of key in the storage of an account in the blockchain.
+func (b *SimulatedBackend) StorageAt(ctx context.Context, contract common.Address, key common.Hash, blockNumber *big.Int) ([]byte, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
 
-	// Assemble the call invocation to measure the gas usage
-	msg := callmsg{
-		from:     from,
-		to:       &contract,
-		gasPrice: new(big.Int),
-		gasLimit: common.MaxBig,
-		value:    new(big.Int),
-		data:     data,
+	if blockNumber != nil && blockNumber.Cmp(b.blockchain.CurrentBlock().Number()) != 0 {
+		return nil, errBlockNumberUnsupported
 	}
-	// Execute the call and return
-	vmenv := core.NewEnv(statedb, chainConfig, b.blockchain, msg, block.Header(), vm.Config{})
-	gaspool := new(core.GasPool).AddGas(common.MaxBig)
+	statedb, _ := b.blockchain.State()
+	if obj := statedb.GetStateObject(contract); obj != nil {
+		val := obj.GetState(key)
+		return val[:], nil
+	}
+	return nil, nil
+}
+
+// TransactionReceipt returns the receipt of a transaction.
+func (b *SimulatedBackend) TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error) {
+	return core.GetReceipt(b.database, txHash), nil
+}
+
+// PendingCodeAt returns the code associated with an account in the pending state.
+func (b *SimulatedBackend) PendingCodeAt(ctx context.Context, contract common.Address) ([]byte, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	return b.pendingState.GetCode(contract), nil
+}
+
+// CallContract executes a contract call.
+func (b *SimulatedBackend) CallContract(ctx context.Context, call ethereum.CallMsg, blockNumber *big.Int) ([]byte, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	if blockNumber != nil && blockNumber.Cmp(b.blockchain.CurrentBlock().Number()) != 0 {
+		return nil, errBlockNumberUnsupported
+	}
+	state, err := b.blockchain.State()
+	if err != nil {
+		return nil, err
+	}
+	rval, _, err := b.callContract(ctx, call, b.blockchain.CurrentBlock(), state)
+	return rval, err
+}
 
-	out, _, err := core.ApplyMessage(vmenv, msg, gaspool)
-	return out, err
+// PendingCallContract executes a contract call on the pending state.
+func (b *SimulatedBackend) PendingCallContract(ctx context.Context, call ethereum.CallMsg) ([]byte, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	rval, _, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState.Copy())
+	return rval, err
 }
 
-// PendingAccountNonce implements ContractTransactor.PendingAccountNonce, retrieving
+// PendingNonceAt implements PendingStateReader.PendingNonceAt, retrieving
 // the nonce currently pending for the account.
-func (b *SimulatedBackend) PendingAccountNonce(ctx context.Context, account common.Address) (uint64, error) {
+func (b *SimulatedBackend) PendingNonceAt(ctx context.Context, account common.Address) (uint64, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
 	return b.pendingState.GetOrNewStateObject(account).Nonce(), nil
 }
 
@@ -140,45 +195,55 @@ func (b *SimulatedBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error
 	return big.NewInt(1), nil
 }
 
-// EstimateGasLimit implements ContractTransactor.EstimateGasLimit, executing the
-// requested code against the currently pending block/state and returning the used
-// gas.
-func (b *SimulatedBackend) EstimateGasLimit(ctx context.Context, sender common.Address, contract *common.Address, value *big.Int, data []byte) (*big.Int, error) {
-	// Create a copy of the currently pending state db to screw around with
-	var (
-		block   = b.pendingBlock
-		statedb = b.pendingState.Copy()
-	)
-	// If there's no code to interact with, respond with an appropriate error
-	if contract != nil {
-		if code := statedb.GetCode(*contract); len(code) == 0 {
-			return nil, bind.ErrNoCode
-		}
-	}
-	// Set infinite balance to the a fake caller account
-	from := statedb.GetOrNewStateObject(sender)
-	from.SetBalance(common.MaxBig)
+// EstimateGas executes the requested code against the currently pending block/state and
+// returns the used amount of gas.
+func (b *SimulatedBackend) EstimateGas(ctx context.Context, call ethereum.CallMsg) (*big.Int, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
 
-	// Assemble the call invocation to measure the gas usage
-	msg := callmsg{
-		from:     from,
-		to:       contract,
-		gasPrice: new(big.Int),
-		gasLimit: common.MaxBig,
-		value:    value,
-		data:     data,
+	_, gas, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState.Copy())
+	return gas, err
+}
+
+// callContract implemens common code between normal and pending contract calls.
+// state is modified during execution, make sure to copy it if necessary.
+func (b *SimulatedBackend) callContract(ctx context.Context, call ethereum.CallMsg, block *types.Block, statedb *state.StateDB) ([]byte, *big.Int, error) {
+	// Ensure message is initialized properly.
+	if call.GasPrice == nil {
+		call.GasPrice = big.NewInt(1)
+	}
+	if call.Gas == nil || call.Gas.BitLen() == 0 {
+		call.Gas = big.NewInt(50000000)
 	}
-	// Execute the call and return
+	if call.Value == nil {
+		call.Value = new(big.Int)
+	}
+	// Set infinite balance to the fake caller account.
+	from := statedb.GetOrNewStateObject(call.From)
+	from.SetBalance(common.MaxBig)
+	// Execute the call.
+	msg := callmsg{call}
 	vmenv := core.NewEnv(statedb, chainConfig, b.blockchain, msg, block.Header(), vm.Config{})
 	gaspool := new(core.GasPool).AddGas(common.MaxBig)
-
-	_, gas, _, err := core.NewStateTransition(vmenv, msg, gaspool).TransitionDb()
-	return gas, err
+	ret, gasUsed, _, err := core.NewStateTransition(vmenv, msg, gaspool).TransitionDb()
+	return ret, gasUsed, err
 }
 
-// SendTransaction implements ContractTransactor.SendTransaction, delegating the raw
-// transaction injection to the remote node.
+// SendTransaction updates the pending block to include the given transaction.
+// It panics if the transaction is invalid.
 func (b *SimulatedBackend) SendTransaction(ctx context.Context, tx *types.Transaction) error {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	sender, err := tx.From()
+	if err != nil {
+		panic(fmt.Errorf("invalid transaction: %v", err))
+	}
+	nonce := b.pendingState.GetNonce(sender)
+	if tx.Nonce() != nonce {
+		panic(fmt.Errorf("invalid transaction nonce: got %d, want %d", tx.Nonce(), nonce))
+	}
+
 	blocks, _ := core.GenerateChain(nil, b.blockchain.CurrentBlock(), b.database, 1, func(number int, block *core.BlockGen) {
 		for _, tx := range b.pendingBlock.Transactions() {
 			block.AddTx(tx)
@@ -187,26 +252,20 @@ func (b *SimulatedBackend) SendTransaction(ctx context.Context, tx *types.Transa
 	})
 	b.pendingBlock = blocks[0]
 	b.pendingState, _ = state.New(b.pendingBlock.Root(), b.database)
-
 	return nil
 }
 
 // callmsg implements core.Message to allow passing it as a transaction simulator.
 type callmsg struct {
-	from     *state.StateObject
-	to       *common.Address
-	gasLimit *big.Int
-	gasPrice *big.Int
-	value    *big.Int
-	data     []byte
+	ethereum.CallMsg
 }
 
-func (m callmsg) From() (common.Address, error)         { return m.from.Address(), nil }
-func (m callmsg) FromFrontier() (common.Address, error) { return m.from.Address(), nil }
+func (m callmsg) From() (common.Address, error)         { return m.CallMsg.From, nil }
+func (m callmsg) FromFrontier() (common.Address, error) { return m.CallMsg.From, nil }
 func (m callmsg) Nonce() uint64                         { return 0 }
 func (m callmsg) CheckNonce() bool                      { return false }
-func (m callmsg) To() *common.Address                   { return m.to }
-func (m callmsg) GasPrice() *big.Int                    { return m.gasPrice }
-func (m callmsg) Gas() *big.Int                         { return m.gasLimit }
-func (m callmsg) Value() *big.Int                       { return m.value }
-func (m callmsg) Data() []byte                          { return m.data }
+func (m callmsg) To() *common.Address                   { return m.CallMsg.To }
+func (m callmsg) GasPrice() *big.Int                    { return m.CallMsg.GasPrice }
+func (m callmsg) Gas() *big.Int                         { return m.CallMsg.Gas }
+func (m callmsg) Value() *big.Int                       { return m.CallMsg.Value }
+func (m callmsg) Data() []byte                          { return m.CallMsg.Data }
diff --git a/accounts/abi/bind/base.go b/accounts/abi/bind/base.go
index 80948d3f1..965f51e85 100644
--- a/accounts/abi/bind/base.go
+++ b/accounts/abi/bind/base.go
@@ -20,8 +20,8 @@ import (
 	"errors"
 	"fmt"
 	"math/big"
-	"sync/atomic"
 
+	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/accounts/abi"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
@@ -62,9 +62,6 @@ type BoundContract struct {
 	abi        abi.ABI            // Reflect based ABI to access the correct Ethereum methods
 	caller     ContractCaller     // Read interface to interact with the blockchain
 	transactor ContractTransactor // Write interface to interact with the blockchain
-
-	latestHasCode  uint32 // Cached verification that the latest state contains code for this contract
-	pendingHasCode uint32 // Cached verification that the pending state contains code for this contract
 }
 
 // NewBoundContract creates a low level contract interface through which calls
@@ -105,25 +102,42 @@ func (c *BoundContract) Call(opts *CallOpts, result interface{}, method string,
 	if opts == nil {
 		opts = new(CallOpts)
 	}
-	// Make sure we have a contract to operate on, and bail out otherwise
-	if (opts.Pending && atomic.LoadUint32(&c.pendingHasCode) == 0) || (!opts.Pending && atomic.LoadUint32(&c.latestHasCode) == 0) {
-		if code, err := c.caller.HasCode(opts.Context, c.address, opts.Pending); err != nil {
-			return err
-		} else if !code {
-			return ErrNoCode
-		}
-		if opts.Pending {
-			atomic.StoreUint32(&c.pendingHasCode, 1)
-		} else {
-			atomic.StoreUint32(&c.latestHasCode, 1)
-		}
-	}
 	// Pack the input, call and unpack the results
 	input, err := c.abi.Pack(method, params...)
 	if err != nil {
 		return err
 	}
-	output, err := c.caller.ContractCall(opts.Context, c.address, input, opts.Pending)
+	var (
+		msg    = ethereum.CallMsg{To: &c.address, Data: input}
+		ctx    = ensureContext(opts.Context)
+		code   []byte
+		output []byte
+	)
+	if opts.Pending {
+		pb, ok := c.caller.(PendingContractCaller)
+		if !ok {
+			return ErrNoPendingState
+		}
+		output, err = pb.PendingCallContract(ctx, msg)
+		if err == nil && len(output) == 0 {
+			// Make sure we have a contract to operate on, and bail out otherwise.
+			if code, err = pb.PendingCodeAt(ctx, c.address); err != nil {
+				return err
+			} else if len(code) == 0 {
+				return ErrNoCode
+			}
+		}
+	} else {
+		output, err = c.caller.CallContract(ctx, msg, nil)
+		if err == nil && len(output) == 0 {
+			// Make sure we have a contract to operate on, and bail out otherwise.
+			if code, err = c.caller.CodeAt(ctx, c.address, nil); err != nil {
+				return err
+			} else if len(code) == 0 {
+				return ErrNoCode
+			}
+		}
+	}
 	if err != nil {
 		return err
 	}
@@ -158,7 +172,7 @@ func (c *BoundContract) transact(opts *TransactOpts, contract *common.Address, i
 	}
 	nonce := uint64(0)
 	if opts.Nonce == nil {
-		nonce, err = c.transactor.PendingAccountNonce(opts.Context, opts.From)
+		nonce, err = c.transactor.PendingNonceAt(ensureContext(opts.Context), opts.From)
 		if err != nil {
 			return nil, fmt.Errorf("failed to retrieve account nonce: %v", err)
 		}
@@ -168,7 +182,7 @@ func (c *BoundContract) transact(opts *TransactOpts, contract *common.Address, i
 	// Figure out the gas allowance and gas price values
 	gasPrice := opts.GasPrice
 	if gasPrice == nil {
-		gasPrice, err = c.transactor.SuggestGasPrice(opts.Context)
+		gasPrice, err = c.transactor.SuggestGasPrice(ensureContext(opts.Context))
 		if err != nil {
 			return nil, fmt.Errorf("failed to suggest gas price: %v", err)
 		}
@@ -176,18 +190,18 @@ func (c *BoundContract) transact(opts *TransactOpts, contract *common.Address, i
 	gasLimit := opts.GasLimit
 	if gasLimit == nil {
 		// Gas estimation cannot succeed without code for method invocations
-		if contract != nil && atomic.LoadUint32(&c.pendingHasCode) == 0 {
-			if code, err := c.transactor.HasCode(opts.Context, c.address, true); err != nil {
+		if contract != nil {
+			if code, err := c.transactor.PendingCodeAt(ensureContext(opts.Context), c.address); err != nil {
 				return nil, err
-			} else if !code {
+			} else if len(code) == 0 {
 				return nil, ErrNoCode
 			}
-			atomic.StoreUint32(&c.pendingHasCode, 1)
 		}
 		// If the contract surely has code (or code is not needed), estimate the transaction
-		gasLimit, err = c.transactor.EstimateGasLimit(opts.Context, opts.From, contract, value, input)
+		msg := ethereum.CallMsg{From: opts.From, To: contract, Value: value, Data: input}
+		gasLimit, err = c.transactor.EstimateGas(ensureContext(opts.Context), msg)
 		if err != nil {
-			return nil, fmt.Errorf("failed to exstimate gas needed: %v", err)
+			return nil, fmt.Errorf("failed to estimate gas needed: %v", err)
 		}
 	}
 	// Create the transaction, sign it and schedule it for execution
@@ -204,8 +218,15 @@ func (c *BoundContract) transact(opts *TransactOpts, contract *common.Address, i
 	if err != nil {
 		return nil, err
 	}
-	if err := c.transactor.SendTransaction(opts.Context, signedTx); err != nil {
+	if err := c.transactor.SendTransaction(ensureContext(opts.Context), signedTx); err != nil {
 		return nil, err
 	}
 	return signedTx, nil
 }
+
+func ensureContext(ctx context.Context) context.Context {
+	if ctx == nil {
+		return context.TODO()
+	}
+	return ctx
+}
diff --git a/accounts/abi/bind/bind_test.go b/accounts/abi/bind/bind_test.go
index a80560821..67c09c3ad 100644
--- a/accounts/abi/bind/bind_test.go
+++ b/accounts/abi/bind/bind_test.go
@@ -44,13 +44,13 @@ var bindTests = []struct {
 		`606060405260068060106000396000f3606060405200`,
 		`[]`,
 		`
-			if b, err := NewEmpty(common.Address{}, backends.NewNilBackend()); b == nil || err != nil {
+			if b, err := NewEmpty(common.Address{}, nil); b == nil || err != nil {
 				t.Fatalf("combined binding (%v) nil or error (%v) not nil", b, nil)
 			}
-			if b, err := NewEmptyCaller(common.Address{}, backends.NewNilBackend()); b == nil || err != nil {
+			if b, err := NewEmptyCaller(common.Address{}, nil); b == nil || err != nil {
 				t.Fatalf("caller binding (%v) nil or error (%v) not nil", b, nil)
 			}
-			if b, err := NewEmptyTransactor(common.Address{}, backends.NewNilBackend()); b == nil || err != nil {
+			if b, err := NewEmptyTransactor(common.Address{}, nil); b == nil || err != nil {
 				t.Fatalf("transactor binding (%v) nil or error (%v) not nil", b, nil)
 			}
 		`,
@@ -62,7 +62,7 @@ var bindTests = []struct {
 		`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`,
 		`[{"constant":true,"inputs":[],"name":"name","outputs":[{"name":"","type":"string"}],"type":"function"},{"constant":false,"inputs":[{"name":"_from","type":"address"},{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transferFrom","outputs":[{"name":"success","type":"bool"}],"type":"function"},{"constant":true,"inputs":[],"name":"decimals","outputs":[{"name":"","type":"uint8"}],"type":"function"},{"constant":true,"inputs":[{"name":"","type":"address"}],"name":"balanceOf","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[],"name":"symbol","outputs":[{"name":"","type":"string"}],"type":"function"},{"constant":false,"inputs":[{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transfer","outputs":[],"type":"function"},{"constant":false,"inputs":[{"name":"_spender","type":"address"},{"name":"_value","type":"uint256"},{"name":"_extraData","type":"bytes"}],"name":"approveAndCall","outputs":[{"name":"success","type":"bool"}],"type":"function"},{"constant":true,"inputs":[{"name":"","type":"address"},{"name":"","type":"address"}],"name":"spentAllowance","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[{"name":"","type":"address"},{"name":"","type":"address"}],"name":"allowance","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"inputs":[{"name":"initialSupply","type":"uint256"},{"name":"tokenName","type":"string"},{"name":"decimalUnits","type":"uint8"},{"name":"tokenSymbol","type":"string"}],"type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"name":"from","type":"address"},{"indexed":true,"name":"to","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Transfer","type":"event"}]`,
 		`
-			if b, err := NewToken(common.Address{}, backends.NewNilBackend()); b == nil || err != nil {
+			if b, err := NewToken(common.Address{}, nil); b == nil || err != nil {
 				t.Fatalf("binding (%v) nil or error (%v) not nil", b, nil)
 			}
 		`,
@@ -73,7 +73,7 @@ var bindTests = []struct {
 		`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`,
 		`[{"constant":false,"inputs":[],"name":"checkGoalReached","outputs":[],"type":"function"},{"constant":true,"inputs":[],"name":"deadline","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[],"name":"beneficiary","outputs":[{"name":"","type":"address"}],"type":"function"},{"constant":true,"inputs":[],"name":"tokenReward","outputs":[{"name":"","type":"address"}],"type":"function"},{"constant":true,"inputs":[],"name":"fundingGoal","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[],"name":"amountRaised","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[],"name":"price","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[{"name":"","type":"uint256"}],"name":"funders","outputs":[{"name":"addr","type":"address"},{"name":"amount","type":"uint256"}],"type":"function"},{"inputs":[{"name":"ifSuccessfulSendTo","type":"address"},{"name":"fundingGoalInEthers","type":"uint256"},{"name":"durationInMinutes","type":"uint256"},{"name":"etherCostOfEachToken","type":"uint256"},{"name":"addressOfTokenUsedAsReward","type":"address"}],"type":"constructor"},{"anonymous":false,"inputs":[{"indexed":false,"name":"backer","type":"address"},{"indexed":false,"name":"amount","type":"uint256"},{"indexed":false,"name":"isContribution","type":"bool"}],"name":"FundTransfer","type":"event"}]`,
 		`
-			if b, err := NewCrowdsale(common.Address{}, backends.NewNilBackend()); b == nil || err != nil {
+			if b, err := NewCrowdsale(common.Address{}, nil); b == nil || err != nil {
 				t.Fatalf("binding (%v) nil or error (%v) not nil", b, nil)
 			}
 		`,
@@ -84,7 +84,7 @@ var bindTests = []struct {
 		`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031916815260200191505b5091505060006040518083038185876185025a03f15050505060048101805460ff191660011761ff00191661010017905561116d565b60048101805460ff191660011761ff00191690555b60068101546005820154600483015460408051888152602081019490945283810192909252610100900460ff166060830152517fd220b7272a8b6d0d7d6bcdace67b936a8f175e6d5c1b3ee438b72256b32ab3af9181900360800190a1509291505056a66cc928b5edb82af9bd49922954155ab7b0942694bea4ce44661d9a8736c688`,
 		`[{"constant":true,"inputs":[{"name":"","type":"uint256"}],"name":"proposals","outputs":[{"name":"recipient","type":"address"},{"name":"amount","type":"uint256"},{"name":"description","type":"string"},{"name":"votingDeadline","type":"uint256"},{"name":"executed","type":"bool"},{"name":"proposalPassed","type":"bool"},{"name":"numberOfVotes","type":"uint256"},{"name":"currentResult","type":"int256"},{"name":"proposalHash","type":"bytes32"}],"type":"function"},{"constant":false,"inputs":[{"name":"proposalNumber","type":"uint256"},{"name":"transactionBytecode","type":"bytes"}],"name":"executeProposal","outputs":[{"name":"result","type":"int256"}],"type":"function"},{"constant":true,"inputs":[{"name":"","type":"address"}],"name":"memberId","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[],"name":"numProposals","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[{"name":"","type":"uint256"}],"name":"members","outputs":[{"name":"member","type":"address"},{"name":"canVote","type":"bool"},{"name":"name","type":"string"},{"name":"memberSince","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[],"name":"debatingPeriodInMinutes","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[],"name":"minimumQuorum","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[],"name":"owner","outputs":[{"name":"","type":"address"}],"type":"function"},{"constant":false,"inputs":[{"name":"targetMember","type":"address"},{"name":"canVote","type":"bool"},{"name":"memberName","type":"string"}],"name":"changeMembership","outputs":[],"type":"function"},{"constant":true,"inputs":[],"name":"majorityMargin","outputs":[{"name":"","type":"int256"}],"type":"function"},{"constant":false,"inputs":[{"name":"beneficiary","type":"address"},{"name":"etherAmount","type":"uint256"},{"name":"JobDescription","type":"string"},{"name":"transactionBytecode","type":"bytes"}],"name":"newProposal","outputs":[{"name":"proposalID","type":"uint256"}],"type":"function"},{"constant":false,"inputs":[{"name":"minimumQuorumForProposals","type":"uint256"},{"name":"minutesForDebate","type":"uint256"},{"name":"marginOfVotesForMajority","type":"int256"}],"name":"changeVotingRules","outputs":[],"type":"function"},{"constant":false,"inputs":[{"name":"proposalNumber","type":"uint256"},{"name":"supportsProposal","type":"bool"},{"name":"justificationText","type":"string"}],"name":"vote","outputs":[{"name":"voteID","type":"uint256"}],"type":"function"},{"constant":true,"inputs":[{"name":"proposalNumber","type":"uint256"},{"name":"beneficiary","type":"address"},{"name":"etherAmount","type":"uint256"},{"name":"transactionBytecode","type":"bytes"}],"name":"checkProposalCode","outputs":[{"name":"codeChecksOut","type":"bool"}],"type":"function"},{"constant":false,"inputs":[{"name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"type":"function"},{"inputs":[{"name":"minimumQuorumForProposals","type":"uint256"},{"name":"minutesForDebate","type":"uint256"},{"name":"marginOfVotesForMajority","type":"int256"},{"name":"congressLeader","type":"address"}],"type":"constructor"},{"anonymous":false,"inputs":[{"indexed":false,"name":"proposalID","type":"uint256"},{"indexed":false,"name":"recipient","type":"address"},{"indexed":false,"name":"amount","type":"uint256"},{"indexed":false,"name":"description","type":"string"}],"name":"ProposalAdded","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"proposalID","type":"uint256"},{"indexed":false,"name":"position","type":"bool"},{"indexed":false,"name":"voter","type":"address"},{"indexed":false,"name":"justification","type":"string"}],"name":"Voted","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"proposalID","type":"uint256"},{"indexed":false,"name":"result","type":"int256"},{"indexed":false,"name":"quorum","type":"uint256"},{"indexed":false,"name":"active","type":"bool"}],"name":"ProposalTallied","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"member","type":"address"},{"indexed":false,"name":"isMember","type":"bool"}],"name":"MembershipChanged","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"minimumQuorum","type":"uint256"},{"indexed":false,"name":"debatingPeriodInMinutes","type":"uint256"},{"indexed":false,"name":"majorityMargin","type":"int256"}],"name":"ChangeOfRules","type":"event"}]`,
 		`
-			if b, err := NewDAO(common.Address{}, backends.NewNilBackend()); b == nil || err != nil {
+			if b, err := NewDAO(common.Address{}, nil); b == nil || err != nil {
 				t.Fatalf("binding (%v) nil or error (%v) not nil", b, nil)
 			}
 		`,
@@ -102,7 +102,7 @@ var bindTests = []struct {
 				{"type":"function","name":"mixedInputs","constant":true,"inputs":[{"name":"","type":"string"},{"name":"str","type":"string"}],"outputs":[]}
 			]
 		`,
-		`if b, err := NewInputChecker(common.Address{}, backends.NewNilBackend()); b == nil || err != nil {
+		`if b, err := NewInputChecker(common.Address{}, nil); b == nil || err != nil {
 			 t.Fatalf("binding (%v) nil or error (%v) not nil", b, nil)
 		 } else if false { // Don't run, just compile and test types
 			 var err error
@@ -130,7 +130,7 @@ var bindTests = []struct {
 				{"type":"function","name":"mixedOutputs","constant":true,"inputs":[],"outputs":[{"name":"","type":"string"},{"name":"str","type":"string"}]}
 			]
 		`,
-		`if b, err := NewOutputChecker(common.Address{}, backends.NewNilBackend()); b == nil || err != nil {
+		`if b, err := NewOutputChecker(common.Address{}, nil); b == nil || err != nil {
 			 t.Fatalf("binding (%v) nil or error (%v) not nil", b, nil)
 		 } else if false { // Don't run, just compile and test types
 			 var str1, str2 string
@@ -376,7 +376,7 @@ func TestBindings(t *testing.T) {
 		t.Skip("go sdk not found for testing")
 	}
 	// Skip the test if the go-ethereum sources are symlinked (https://github.com/golang/go/issues/14845)
-	linkTestCode := fmt.Sprintf("package linktest\nfunc CheckSymlinks(){\nfmt.Println(backends.NewNilBackend())\n}")
+	linkTestCode := fmt.Sprintf("package linktest\nfunc CheckSymlinks(){\nfmt.Println(backends.NewSimulatedBackend())\n}")
 	linkTestDeps, err := imports.Process("", []byte(linkTestCode), nil)
 	if err != nil {
 		t.Fatalf("failed check for goimports symlink bug: %v", err)
diff --git a/accounts/abi/bind/template.go b/accounts/abi/bind/template.go
index 72998bb6d..523122213 100644
--- a/accounts/abi/bind/template.go
+++ b/accounts/abi/bind/template.go
@@ -127,7 +127,7 @@ package {{.Package}}
 
 	// New{{.Type}} creates a new instance of {{.Type}}, bound to a specific deployed contract.
 	func New{{.Type}}(address common.Address, backend bind.ContractBackend) (*{{.Type}}, error) {
-	  contract, err := bind{{.Type}}(address, backend.(bind.ContractCaller), backend.(bind.ContractTransactor))
+	  contract, err := bind{{.Type}}(address, backend, backend)
 	  if err != nil {
 	    return nil, err
 	  }
diff --git a/accounts/abi/bind/util.go b/accounts/abi/bind/util.go
new file mode 100644
index 000000000..bbb6d6a75
--- /dev/null
+++ b/accounts/abi/bind/util.go
@@ -0,0 +1,76 @@
+// Copyright 2016 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 bind
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/logger"
+	"github.com/ethereum/go-ethereum/logger/glog"
+	"golang.org/x/net/context"
+)
+
+// WaitMined waits for tx to be mined on the blockchain.
+// It stops waiting when the context is canceled.
+func WaitMined(ctx context.Context, b DeployBackend, tx *types.Transaction) (*types.Receipt, error) {
+	queryTicker := time.NewTicker(1 * time.Second)
+	defer queryTicker.Stop()
+	loghash := tx.Hash().Hex()[:8]
+	for {
+		receipt, err := b.TransactionReceipt(ctx, tx.Hash())
+		if receipt != nil {
+			return receipt, nil
+		}
+		if err != nil {
+			glog.V(logger.Detail).Infof("tx %x error: %v", loghash, err)
+		} else {
+			glog.V(logger.Detail).Infof("tx %x not yet mined...", loghash)
+		}
+		// Wait for the next round.
+		select {
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		case <-queryTicker.C:
+		}
+	}
+}
+
+// WaitDeployed waits for a contract deployment transaction and returns the on-chain
+// contract address when it is mined. It stops waiting when ctx is canceled.
+func WaitDeployed(ctx context.Context, b DeployBackend, tx *types.Transaction) (common.Address, error) {
+	if tx.To() != nil {
+		return common.Address{}, fmt.Errorf("tx is not contract creation")
+	}
+	receipt, err := WaitMined(ctx, b, tx)
+	if err != nil {
+		return common.Address{}, err
+	}
+	if receipt.ContractAddress == (common.Address{}) {
+		return common.Address{}, fmt.Errorf("zero address")
+	}
+	// Check that code has indeed been deployed at the address.
+	// This matters on pre-Homestead chains: OOG in the constructor
+	// could leave an empty account behind.
+	code, err := b.CodeAt(ctx, receipt.ContractAddress, nil)
+	if err == nil && len(code) == 0 {
+		err = ErrNoCodeAfterDeploy
+	}
+	return receipt.ContractAddress, err
+}
diff --git a/accounts/abi/bind/util_test.go b/accounts/abi/bind/util_test.go
new file mode 100644
index 000000000..192fa4f4c
--- /dev/null
+++ b/accounts/abi/bind/util_test.go
@@ -0,0 +1,93 @@
+// Copyright 2016 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 bind_test
+
+import (
+	"math/big"
+	"testing"
+	"time"
+
+	"github.com/ethereum/go-ethereum/accounts/abi/bind"
+	"github.com/ethereum/go-ethereum/accounts/abi/bind/backends"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
+	"golang.org/x/net/context"
+)
+
+var testKey, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
+
+var waitDeployedTests = map[string]struct {
+	code        string
+	gas         *big.Int
+	wantAddress common.Address
+	wantErr     error
+}{
+	"successful deploy": {
+		code:        `6060604052600a8060106000396000f360606040526008565b00`,
+		gas:         big.NewInt(3000000),
+		wantAddress: common.HexToAddress("0x3a220f351252089d385b29beca14e27f204c296a"),
+	},
+	"empty code": {
+		code:        ``,
+		gas:         big.NewInt(300000),
+		wantErr:     bind.ErrNoCodeAfterDeploy,
+		wantAddress: common.HexToAddress("0x3a220f351252089d385b29beca14e27f204c296a"),
+	},
+}
+
+func TestWaitDeployed(t *testing.T) {
+	for name, test := range waitDeployedTests {
+		backend := backends.NewSimulatedBackend(core.GenesisAccount{
+			Address: crypto.PubkeyToAddress(testKey.PublicKey),
+			Balance: big.NewInt(10000000000),
+		})
+
+		// Create the transaction.
+		tx := types.NewContractCreation(0, big.NewInt(0), test.gas, big.NewInt(1), common.FromHex(test.code))
+		tx, _ = tx.SignECDSA(testKey)
+
+		// Wait for it to get mined in the background.
+		var (
+			err     error
+			address common.Address
+			mined   = make(chan struct{})
+			ctx     = context.Background()
+		)
+		go func() {
+			address, err = bind.WaitDeployed(ctx, backend, tx)
+			close(mined)
+		}()
+
+		// Send and mine the transaction.
+		backend.SendTransaction(ctx, tx)
+		backend.Commit()
+
+		select {
+		case <-mined:
+			if err != test.wantErr {
+				t.Errorf("test %q: error mismatch: got %q, want %q", name, err, test.wantErr)
+			}
+			if address != test.wantAddress {
+				t.Errorf("test %q: unexpected contract address %s", name, address.Hex())
+			}
+		case <-time.After(2 * time.Second):
+			t.Errorf("test %q: timeout", name)
+		}
+	}
+}
diff --git a/core/types/block.go b/core/types/block.go
index 599359247..559fbdd20 100644
--- a/core/types/block.go
+++ b/core/types/block.go
@@ -18,9 +18,9 @@
 package types
 
 import (
-	"bytes"
 	"encoding/binary"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"math/big"
@@ -33,25 +33,53 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
+var (
+	EmptyRootHash  = DeriveSha(Transactions{})
+	EmptyUncleHash = CalcUncleHash(nil)
+)
+
+var (
+	errMissingHeaderMixDigest = errors.New("missing mixHash in JSON block header")
+	errMissingHeaderFields    = errors.New("missing required JSON block header fields")
+	errBadNonceSize           = errors.New("invalid block nonce size, want 8 bytes")
+)
+
 // A BlockNonce is a 64-bit hash which proves (combined with the
 // mix-hash) that a sufficient amount of computation has been carried
 // out on a block.
 type BlockNonce [8]byte
 
+// EncodeNonce converts the given integer to a block nonce.
 func EncodeNonce(i uint64) BlockNonce {
 	var n BlockNonce
 	binary.BigEndian.PutUint64(n[:], i)
 	return n
 }
 
+// Uint64 returns the integer value of a block nonce.
 func (n BlockNonce) Uint64() uint64 {
 	return binary.BigEndian.Uint64(n[:])
 }
 
+// MarshalJSON implements json.Marshaler
 func (n BlockNonce) MarshalJSON() ([]byte, error) {
 	return []byte(fmt.Sprintf(`"0x%x"`, n)), nil
 }
 
+// UnmarshalJSON implements json.Unmarshaler
+func (n *BlockNonce) UnmarshalJSON(input []byte) error {
+	var b hexBytes
+	if err := b.UnmarshalJSON(input); err != nil {
+		return err
+	}
+	if len(b) != 8 {
+		return errBadNonceSize
+	}
+	copy((*n)[:], b)
+	return nil
+}
+
+// Header represents Ethereum block headers.
 type Header struct {
 	ParentHash  common.Hash    // Hash to the previous block
 	UncleHash   common.Hash    // Uncles of this block
@@ -70,10 +98,31 @@ type Header struct {
 	Nonce       BlockNonce
 }
 
+type jsonHeader struct {
+	ParentHash  *common.Hash    `json:"parentHash"`
+	UncleHash   *common.Hash    `json:"sha3Uncles"`
+	Coinbase    *common.Address `json:"miner"`
+	Root        *common.Hash    `json:"stateRoot"`
+	TxHash      *common.Hash    `json:"transactionsRoot"`
+	ReceiptHash *common.Hash    `json:"receiptRoot"`
+	Bloom       *Bloom          `json:"logsBloom"`
+	Difficulty  *hexBig         `json:"difficulty"`
+	Number      *hexBig         `json:"number"`
+	GasLimit    *hexBig         `json:"gasLimit"`
+	GasUsed     *hexBig         `json:"gasUsed"`
+	Time        *hexBig         `json:"timestamp"`
+	Extra       *hexBytes       `json:"extraData"`
+	MixDigest   *common.Hash    `json:"mixHash"`
+	Nonce       *BlockNonce     `json:"nonce"`
+}
+
+// Hash returns the block hash of the header, which is simply the keccak256 hash of its
+// RLP encoding.
 func (h *Header) Hash() common.Hash {
 	return rlpHash(h)
 }
 
+// HashNoNonce returns the hash which is used as input for the proof-of-work search.
 func (h *Header) HashNoNonce() common.Hash {
 	return rlpHash([]interface{}{
 		h.ParentHash,
@@ -92,48 +141,63 @@ func (h *Header) HashNoNonce() common.Hash {
 	})
 }
 
-func (h *Header) UnmarshalJSON(data []byte) error {
-	var ext struct {
-		ParentHash string
-		Coinbase   string
-		Difficulty string
-		GasLimit   string
-		Time       *big.Int
-		Extra      string
-	}
-	dec := json.NewDecoder(bytes.NewReader(data))
-	if err := dec.Decode(&ext); err != nil {
-		return err
-	}
-
-	h.ParentHash = common.HexToHash(ext.ParentHash)
-	h.Coinbase = common.HexToAddress(ext.Coinbase)
-	h.Difficulty = common.String2Big(ext.Difficulty)
-	h.Time = ext.Time
-	h.Extra = []byte(ext.Extra)
-	return nil
+// MarshalJSON encodes headers into the web3 RPC response block format.
+func (h *Header) MarshalJSON() ([]byte, error) {
+	return json.Marshal(&jsonHeader{
+		ParentHash:  &h.ParentHash,
+		UncleHash:   &h.UncleHash,
+		Coinbase:    &h.Coinbase,
+		Root:        &h.Root,
+		TxHash:      &h.TxHash,
+		ReceiptHash: &h.ReceiptHash,
+		Bloom:       &h.Bloom,
+		Difficulty:  (*hexBig)(h.Difficulty),
+		Number:      (*hexBig)(h.Number),
+		GasLimit:    (*hexBig)(h.GasLimit),
+		GasUsed:     (*hexBig)(h.GasUsed),
+		Time:        (*hexBig)(h.Time),
+		Extra:       (*hexBytes)(&h.Extra),
+		MixDigest:   &h.MixDigest,
+		Nonce:       &h.Nonce,
+	})
 }
 
-func (h *Header) MarshalJSON() ([]byte, error) {
-	fields := map[string]interface{}{
-		"hash":             h.Hash(),
-		"parentHash":       h.ParentHash,
-		"number":           fmt.Sprintf("%#x", h.Number),
-		"nonce":            h.Nonce,
-		"receiptRoot":      h.ReceiptHash,
-		"logsBloom":        h.Bloom,
-		"sha3Uncles":       h.UncleHash,
-		"stateRoot":        h.Root,
-		"miner":            h.Coinbase,
-		"difficulty":       fmt.Sprintf("%#x", h.Difficulty),
-		"extraData":        fmt.Sprintf("0x%x", h.Extra),
-		"gasLimit":         fmt.Sprintf("%#x", h.GasLimit),
-		"gasUsed":          fmt.Sprintf("%#x", h.GasUsed),
-		"timestamp":        fmt.Sprintf("%#x", h.Time),
-		"transactionsRoot": h.TxHash,
+// UnmarshalJSON decodes headers from the web3 RPC response block format.
+func (h *Header) UnmarshalJSON(input []byte) error {
+	var dec jsonHeader
+	if err := json.Unmarshal(input, &dec); err != nil {
+		return err
 	}
-
-	return json.Marshal(fields)
+	// Ensure that all fields are set. MixDigest is checked separately because
+	// it is a recent addition to the spec (as of August 2016) and older RPC server
+	// implementations might not provide it.
+	if dec.MixDigest == nil {
+		return errMissingHeaderMixDigest
+	}
+	if dec.ParentHash == nil || dec.UncleHash == nil || dec.Coinbase == nil ||
+		dec.Root == nil || dec.TxHash == nil || dec.ReceiptHash == nil ||
+		dec.Bloom == nil || dec.Difficulty == nil || dec.Number == nil ||
+		dec.GasLimit == nil || dec.GasUsed == nil || dec.Time == nil ||
+		dec.Extra == nil || dec.Nonce == nil {
+		return errMissingHeaderFields
+	}
+	// Assign all values.
+	h.ParentHash = *dec.ParentHash
+	h.UncleHash = *dec.UncleHash
+	h.Coinbase = *dec.Coinbase
+	h.Root = *dec.Root
+	h.TxHash = *dec.TxHash
+	h.ReceiptHash = *dec.ReceiptHash
+	h.Bloom = *dec.Bloom
+	h.Difficulty = (*big.Int)(dec.Difficulty)
+	h.Number = (*big.Int)(dec.Number)
+	h.GasLimit = (*big.Int)(dec.GasLimit)
+	h.GasUsed = (*big.Int)(dec.GasUsed)
+	h.Time = (*big.Int)(dec.Time)
+	h.Extra = *dec.Extra
+	h.MixDigest = *dec.MixDigest
+	h.Nonce = *dec.Nonce
+	return nil
 }
 
 func rlpHash(x interface{}) (h common.Hash) {
@@ -150,6 +214,7 @@ type Body struct {
 	Uncles       []*Header
 }
 
+// Block represents a block in the Ethereum blockchain.
 type Block struct {
 	header       *Header
 	uncles       []*Header
@@ -198,11 +263,6 @@ type storageblock struct {
 	TD     *big.Int
 }
 
-var (
-	EmptyRootHash  = DeriveSha(Transactions{})
-	EmptyUncleHash = CalcUncleHash(nil)
-)
-
 // NewBlock creates a new block. The input data is copied,
 // changes to header and to the field values will not affect the
 // block.
@@ -275,23 +335,7 @@ func CopyHeader(h *Header) *Header {
 	return &cpy
 }
 
-func (b *Block) ValidateFields() error {
-	if b.header == nil {
-		return fmt.Errorf("header is nil")
-	}
-	for i, transaction := range b.transactions {
-		if transaction == nil {
-			return fmt.Errorf("transaction %d is nil", i)
-		}
-	}
-	for i, uncle := range b.uncles {
-		if uncle == nil {
-			return fmt.Errorf("uncle %d is nil", i)
-		}
-	}
-	return nil
-}
-
+// DecodeRLP decodes the Ethereum
 func (b *Block) DecodeRLP(s *rlp.Stream) error {
 	var eb extblock
 	_, size, _ := s.Kind()
@@ -303,6 +347,7 @@ func (b *Block) DecodeRLP(s *rlp.Stream) error {
 	return nil
 }
 
+// EncodeRLP serializes b into the Ethereum RLP block format.
 func (b *Block) EncodeRLP(w io.Writer) error {
 	return rlp.Encode(w, extblock{
 		Header: b.header,
@@ -322,6 +367,7 @@ func (b *StorageBlock) DecodeRLP(s *rlp.Stream) error {
 }
 
 // TODO: copies
+
 func (b *Block) Uncles() []*Header          { return b.uncles }
 func (b *Block) Transactions() Transactions { return b.transactions }
 
@@ -409,8 +455,8 @@ func (b *Block) WithBody(transactions []*Transaction, uncles []*Header) *Block {
 	return block
 }
 
-// Implement pow.Block
-
+// Hash returns the keccak256 hash of b's header.
+// The hash is computed on the first call and cached thereafter.
 func (b *Block) Hash() common.Hash {
 	if hash := b.hash.Load(); hash != nil {
 		return hash.(common.Hash)
diff --git a/core/types/bloom9.go b/core/types/bloom9.go
index ecf2bffc2..d3945a734 100644
--- a/core/types/bloom9.go
+++ b/core/types/bloom9.go
@@ -31,28 +31,34 @@ type bytesBacked interface {
 
 const bloomLength = 256
 
+// Bloom represents a 256 bit bloom filter.
 type Bloom [bloomLength]byte
 
+// BytesToBloom converts a byte slice to a bloom filter.
+// It panics if b is not of suitable size.
 func BytesToBloom(b []byte) Bloom {
 	var bloom Bloom
 	bloom.SetBytes(b)
 	return bloom
 }
 
+// SetBytes sets the content of b to the given bytes.
+// It panics if d is not of suitable size.
 func (b *Bloom) SetBytes(d []byte) {
 	if len(b) < len(d) {
 		panic(fmt.Sprintf("bloom bytes too big %d %d", len(b), len(d)))
 	}
-
 	copy(b[bloomLength-len(d):], d)
 }
 
+// Add adds d to the filter. Future calls of Test(d) will return true.
 func (b *Bloom) Add(d *big.Int) {
 	bin := new(big.Int).SetBytes(b[:])
 	bin.Or(bin, bloom9(d.Bytes()))
 	b.SetBytes(bin.Bytes())
 }
 
+// Big converts b to a big integer.
 func (b Bloom) Big() *big.Int {
 	return common.Bytes2Big(b[:])
 }
@@ -69,8 +75,22 @@ func (b Bloom) TestBytes(test []byte) bool {
 	return b.Test(common.BytesToBig(test))
 }
 
+// MarshalJSON encodes b as a hex string with 0x prefix.
 func (b Bloom) MarshalJSON() ([]byte, error) {
-	return []byte(fmt.Sprintf(`"%#x"`, b.Bytes())), nil
+	return []byte(fmt.Sprintf(`"%#x"`, b[:])), nil
+}
+
+// UnmarshalJSON b as a hex string with 0x prefix.
+func (b *Bloom) UnmarshalJSON(input []byte) error {
+	var dec hexBytes
+	if err := dec.UnmarshalJSON(input); err != nil {
+		return err
+	}
+	if len(dec) != bloomLength {
+		return fmt.Errorf("invalid bloom size, want %d bytes", bloomLength)
+	}
+	copy((*b)[:], dec)
+	return nil
 }
 
 func CreateBloom(receipts Receipts) Bloom {
diff --git a/core/types/json.go b/core/types/json.go
new file mode 100644
index 000000000..403e79899
--- /dev/null
+++ b/core/types/json.go
@@ -0,0 +1,87 @@
+// Copyright 2016 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 types
+
+import (
+	"encoding/hex"
+	"fmt"
+	"math/big"
+)
+
+// JSON unmarshaling utilities.
+
+type hexBytes []byte
+
+func (b *hexBytes) UnmarshalJSON(input []byte) error {
+	if len(input) < 2 || input[0] != '"' || input[len(input)-1] != '"' {
+		return fmt.Errorf("cannot unmarshal non-string into hexBytes")
+	}
+	input = input[1 : len(input)-1]
+	if len(input) < 2 || input[0] != '0' || input[1] != 'x' {
+		return fmt.Errorf("missing 0x prefix in hexBytes input %q", input)
+	}
+	dec := make(hexBytes, (len(input)-2)/2)
+	if _, err := hex.Decode(dec, input[2:]); err != nil {
+		return err
+	}
+	*b = dec
+	return nil
+}
+
+type hexBig big.Int
+
+func (b *hexBig) UnmarshalJSON(input []byte) error {
+	raw, err := checkHexNumber(input)
+	if err != nil {
+		return err
+	}
+	dec, ok := new(big.Int).SetString(string(raw), 16)
+	if !ok {
+		return fmt.Errorf("invalid hex number")
+	}
+	*b = (hexBig)(*dec)
+	return nil
+}
+
+type hexUint64 uint64
+
+func (b *hexUint64) UnmarshalJSON(input []byte) error {
+	raw, err := checkHexNumber(input)
+	if err != nil {
+		return err
+	}
+	_, err = fmt.Sscanf(string(raw), "%x", b)
+	return err
+}
+
+func checkHexNumber(input []byte) (raw []byte, err error) {
+	if len(input) < 2 || input[0] != '"' || input[len(input)-1] != '"' {
+		return nil, fmt.Errorf("cannot unmarshal non-string into hex number")
+	}
+	input = input[1 : len(input)-1]
+	if len(input) < 2 || input[0] != '0' || input[1] != 'x' {
+		return nil, fmt.Errorf("missing 0x prefix in hex number input %q", input)
+	}
+	if len(input) == 2 {
+		return nil, fmt.Errorf("empty hex number")
+	}
+	raw = input[2:]
+	if len(raw)%2 != 0 {
+		raw = append([]byte{'0'}, raw...)
+	}
+	return raw, nil
+}
diff --git a/core/types/json_test.go b/core/types/json_test.go
new file mode 100644
index 000000000..5f422b873
--- /dev/null
+++ b/core/types/json_test.go
@@ -0,0 +1,136 @@
+package types
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+var unmarshalHeaderTests = map[string]struct {
+	input     string
+	wantHash  common.Hash
+	wantError error
+}{
+	"block 0x1e2200": {
+		input:    `{"difficulty":"0x311ca98cebfe","extraData":"0x7777772e62772e636f6d","gasLimit":"0x47db3d","gasUsed":"0x43760c","hash":"0x3724bc6b9dcd4a2b3a26e0ed9b821e7380b5b3d7dec7166c7983cead62a37e48","logsBloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","miner":"0xbcdfc35b86bedf72f0cda046a3c16829a2ef41d1","mixHash":"0x1ccfddb506dac5afc09b6f92eb09a043ffc8e08f7592250af57b9c64c20f9b25","nonce":"0x670bd98c79585197","number":"0x1e2200","parentHash":"0xd3e13296d064e7344f20c57c57b67a022f6bf7741fa42428c2db77e91abdf1f8","receiptRoot":"0xeeab1776c1fafbe853a8ee0c1bafe2e775a1b6fdb6ff3e9f9410ddd4514889ff","sha3Uncles":"0x5fbfa4ec8b089678c53b6798cc0d9260ea40a529e06d5300aae35596262e0eb3","size":"0x57f","stateRoot":"0x62ad2007e4a3f31ea98e5d2fd150d894887bafde36eeac7331a60ae12053ec76","timestamp":"0x579b82f2","totalDifficulty":"0x24fe813c101d00f97","transactions":["0xb293408e85735bfc78b35aa89de8b48e49641e3d82e3d52ea2d44ec42a4e88cf","0x124acc383ff2da6faa0357829084dae64945221af6f6f09da1d11688b779f939","0xee090208b6051c442ccdf9ec19f66389e604d342a6d71144c7227ce995bef46f"],"transactionsRoot":"0xce0042dd9af0c1923dd7f58ca6faa156d39d4ef39fdb65c5bcd1d4b4720096db","uncles":["0x6818a31d1f204cf640c952082940b68b8db6d1b39ee71f7efe0e3629ed5d7eb3"]}`,
+		wantHash: common.HexToHash("0x3724bc6b9dcd4a2b3a26e0ed9b821e7380b5b3d7dec7166c7983cead62a37e48"),
+	},
+	"bad nonce": {
+		input:     `{"difficulty":"0x311ca98cebfe","extraData":"0x7777772e62772e636f6d","gasLimit":"0x47db3d","gasUsed":"0x43760c","hash":"0x3724bc6b9dcd4a2b3a26e0ed9b821e7380b5b3d7dec7166c7983cead62a37e48","logsBloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","miner":"0xbcdfc35b86bedf72f0cda046a3c16829a2ef41d1","mixHash":"0x1ccfddb506dac5afc09b6f92eb09a043ffc8e08f7592250af57b9c64c20f9b25","nonce":"0x670bd98c7958","number":"0x1e2200","parentHash":"0xd3e13296d064e7344f20c57c57b67a022f6bf7741fa42428c2db77e91abdf1f8","receiptRoot":"0xeeab1776c1fafbe853a8ee0c1bafe2e775a1b6fdb6ff3e9f9410ddd4514889ff","sha3Uncles":"0x5fbfa4ec8b089678c53b6798cc0d9260ea40a529e06d5300aae35596262e0eb3","size":"0x57f","stateRoot":"0x62ad2007e4a3f31ea98e5d2fd150d894887bafde36eeac7331a60ae12053ec76","timestamp":"0x579b82f2","totalDifficulty":"0x24fe813c101d00f97","transactions":["0xb293408e85735bfc78b35aa89de8b48e49641e3d82e3d52ea2d44ec42a4e88cf","0x124acc383ff2da6faa0357829084dae64945221af6f6f09da1d11688b779f939","0xee090208b6051c442ccdf9ec19f66389e604d342a6d71144c7227ce995bef46f"],"transactionsRoot":"0xce0042dd9af0c1923dd7f58ca6faa156d39d4ef39fdb65c5bcd1d4b4720096db","uncles":["0x6818a31d1f204cf640c952082940b68b8db6d1b39ee71f7efe0e3629ed5d7eb3"]}`,
+		wantError: errBadNonceSize,
+	},
+	"missing mixHash": {
+		input:     `{"difficulty":"0x311ca98cebfe","extraData":"0x7777772e62772e636f6d","gasLimit":"0x47db3d","gasUsed":"0x43760c","hash":"0x3724bc6b9dcd4a2b3a26e0ed9b821e7380b5b3d7dec7166c7983cead62a37e48","logsBloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","miner":"0xbcdfc35b86bedf72f0cda046a3c16829a2ef41d1","nonce":"0x670bd98c79585197","number":"0x1e2200","parentHash":"0xd3e13296d064e7344f20c57c57b67a022f6bf7741fa42428c2db77e91abdf1f8","receiptRoot":"0xeeab1776c1fafbe853a8ee0c1bafe2e775a1b6fdb6ff3e9f9410ddd4514889ff","sha3Uncles":"0x5fbfa4ec8b089678c53b6798cc0d9260ea40a529e06d5300aae35596262e0eb3","size":"0x57f","stateRoot":"0x62ad2007e4a3f31ea98e5d2fd150d894887bafde36eeac7331a60ae12053ec76","timestamp":"0x579b82f2","totalDifficulty":"0x24fe813c101d00f97","transactions":["0xb293408e85735bfc78b35aa89de8b48e49641e3d82e3d52ea2d44ec42a4e88cf","0x124acc383ff2da6faa0357829084dae64945221af6f6f09da1d11688b779f939","0xee090208b6051c442ccdf9ec19f66389e604d342a6d71144c7227ce995bef46f"],"transactionsRoot":"0xce0042dd9af0c1923dd7f58ca6faa156d39d4ef39fdb65c5bcd1d4b4720096db","uncles":["0x6818a31d1f204cf640c952082940b68b8db6d1b39ee71f7efe0e3629ed5d7eb3"]}`,
+		wantError: errMissingHeaderMixDigest,
+	},
+	"missing fields": {
+		input:     `{"gasLimit":"0x47db3d","gasUsed":"0x43760c","hash":"0x3724bc6b9dcd4a2b3a26e0ed9b821e7380b5b3d7dec7166c7983cead62a37e48","logsBloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","miner":"0xbcdfc35b86bedf72f0cda046a3c16829a2ef41d1","mixHash":"0x1ccfddb506dac5afc09b6f92eb09a043ffc8e08f7592250af57b9c64c20f9b25","nonce":"0x670bd98c79585197","number":"0x1e2200","parentHash":"0xd3e13296d064e7344f20c57c57b67a022f6bf7741fa42428c2db77e91abdf1f8","receiptRoot":"0xeeab1776c1fafbe853a8ee0c1bafe2e775a1b6fdb6ff3e9f9410ddd4514889ff","sha3Uncles":"0x5fbfa4ec8b089678c53b6798cc0d9260ea40a529e06d5300aae35596262e0eb3","size":"0x57f","stateRoot":"0x62ad2007e4a3f31ea98e5d2fd150d894887bafde36eeac7331a60ae12053ec76","timestamp":"0x579b82f2","totalDifficulty":"0x24fe813c101d00f97","transactions":["0xb293408e85735bfc78b35aa89de8b48e49641e3d82e3d52ea2d44ec42a4e88cf","0x124acc383ff2da6faa0357829084dae64945221af6f6f09da1d11688b779f939","0xee090208b6051c442ccdf9ec19f66389e604d342a6d71144c7227ce995bef46f"],"transactionsRoot":"0xce0042dd9af0c1923dd7f58ca6faa156d39d4ef39fdb65c5bcd1d4b4720096db","uncles":["0x6818a31d1f204cf640c952082940b68b8db6d1b39ee71f7efe0e3629ed5d7eb3"]}`,
+		wantError: errMissingHeaderFields,
+	},
+}
+
+func TestUnmarshalHeader(t *testing.T) {
+	for name, test := range unmarshalHeaderTests {
+		var head *Header
+		err := json.Unmarshal([]byte(test.input), &head)
+		if !checkError(t, name, err, test.wantError) {
+			continue
+		}
+		if head.Hash() != test.wantHash {
+			t.Errorf("test %q: got hash %x, want %x", name, head.Hash(), test.wantHash)
+			continue
+		}
+	}
+}
+
+var unmarshalTransactionTests = map[string]struct {
+	input     string
+	wantHash  common.Hash
+	wantFrom  common.Address
+	wantError error
+}{
+	"value transfer": {
+		input:    `{"blockHash":"0x0188a05dcc825bd1a05dab91bea0c03622542683446e56302eabb46097d4ae11","blockNumber":"0x1e478d","from":"0xf36c3f6c4a2ce8d353fb92d5cd10d19ce69ae689","gas":"0x15f90","gasPrice":"0x4a817c800","hash":"0xd91c08f1e27c5ce7e1f57d78d7c56a9ee446be07b9635d84d0475660ea8905e9","input":"0x","nonce":"0x58d","to":"0x88f252f674ac755feff877abf957d4aa05adce86","transactionIndex":"0x1","value":"0x19f0ec3ed71ec00","v":"0x1c","r":"0x53829f206c99b866672f987909d556cd1c2eb60e990a3425f65083977c14187b","s":"0x5cc52383e41c923ec7d63749c1f13a7236b540527ee5b9a78b3fb869a66f60e"}`,
+		wantHash: common.HexToHash("0xd91c08f1e27c5ce7e1f57d78d7c56a9ee446be07b9635d84d0475660ea8905e9"),
+		wantFrom: common.HexToAddress("0xf36c3f6c4a2ce8d353fb92d5cd10d19ce69ae689"),
+	},
+	"bad signature fields": {
+		input:     `{"blockHash":"0x0188a05dcc825bd1a05dab91bea0c03622542683446e56302eabb46097d4ae11","blockNumber":"0x1e478d","from":"0xf36c3f6c4a2ce8d353fb92d5cd10d19ce69ae689","gas":"0x15f90","gasPrice":"0x4a817c800","hash":"0xd91c08f1e27c5ce7e1f57d78d7c56a9ee446be07b9635d84d0475660ea8905e9","input":"0x","nonce":"0x58d","to":"0x88f252f674ac755feff877abf957d4aa05adce86","transactionIndex":"0x1","value":"0x19f0ec3ed71ec00","v":"0x58","r":"0x53829f206c99b866672f987909d556cd1c2eb60e990a3425f65083977c14187b","s":"0x5cc52383e41c923ec7d63749c1f13a7236b540527ee5b9a78b3fb869a66f60e"}`,
+		wantError: ErrInvalidSig,
+	},
+	"missing signature v": {
+		input:     `{"blockHash":"0x0188a05dcc825bd1a05dab91bea0c03622542683446e56302eabb46097d4ae11","blockNumber":"0x1e478d","from":"0xf36c3f6c4a2ce8d353fb92d5cd10d19ce69ae689","gas":"0x15f90","gasPrice":"0x4a817c800","hash":"0xd91c08f1e27c5ce7e1f57d78d7c56a9ee446be07b9635d84d0475660ea8905e9","input":"0x","nonce":"0x58d","to":"0x88f252f674ac755feff877abf957d4aa05adce86","transactionIndex":"0x1","value":"0x19f0ec3ed71ec00","r":"0x53829f206c99b866672f987909d556cd1c2eb60e990a3425f65083977c14187b","s":"0x5cc52383e41c923ec7d63749c1f13a7236b540527ee5b9a78b3fb869a66f60e"}`,
+		wantError: errMissingTxSignatureFields,
+	},
+	"missing signature fields": {
+		input:     `{"blockHash":"0x0188a05dcc825bd1a05dab91bea0c03622542683446e56302eabb46097d4ae11","blockNumber":"0x1e478d","from":"0xf36c3f6c4a2ce8d353fb92d5cd10d19ce69ae689","gas":"0x15f90","gasPrice":"0x4a817c800","hash":"0xd91c08f1e27c5ce7e1f57d78d7c56a9ee446be07b9635d84d0475660ea8905e9","input":"0x","nonce":"0x58d","to":"0x88f252f674ac755feff877abf957d4aa05adce86","transactionIndex":"0x1","value":"0x19f0ec3ed71ec00"}`,
+		wantError: errMissingTxSignatureFields,
+	},
+	"missing fields": {
+		input:     `{"blockHash":"0x0188a05dcc825bd1a05dab91bea0c03622542683446e56302eabb46097d4ae11","blockNumber":"0x1e478d","from":"0xf36c3f6c4a2ce8d353fb92d5cd10d19ce69ae689","hash":"0xd91c08f1e27c5ce7e1f57d78d7c56a9ee446be07b9635d84d0475660ea8905e9","input":"0x","nonce":"0x58d","to":"0x88f252f674ac755feff877abf957d4aa05adce86","transactionIndex":"0x1","value":"0x19f0ec3ed71ec00","v":"0x1c","r":"0x53829f206c99b866672f987909d556cd1c2eb60e990a3425f65083977c14187b","s":"0x5cc52383e41c923ec7d63749c1f13a7236b540527ee5b9a78b3fb869a66f60e"}`,
+		wantError: errMissingTxFields,
+	},
+}
+
+func TestUnmarshalTransaction(t *testing.T) {
+	for name, test := range unmarshalTransactionTests {
+		var tx *Transaction
+		err := json.Unmarshal([]byte(test.input), &tx)
+		if !checkError(t, name, err, test.wantError) {
+			continue
+		}
+		if tx.Hash() != test.wantHash {
+			t.Errorf("test %q: got hash %x, want %x", name, tx.Hash(), test.wantHash)
+			continue
+		}
+		from, err := tx.From()
+		if err != nil {
+			t.Errorf("test %q: From error %v", name, err)
+		}
+		if from != test.wantFrom {
+			t.Errorf("test %q: sender mismatch: got %x, want %x", name, from, test.wantFrom)
+		}
+	}
+}
+
+var unmarshalReceiptTests = map[string]struct {
+	input     string
+	wantError error
+}{
+	"ok": {
+		input: `{"blockHash":"0xad20a0f78d19d7857067a9c06e6411efeab7673e183e4a545f53b724bb7fabf0","blockNumber":"0x1e773b","contractAddress":null,"cumulativeGasUsed":"0x10cea","from":"0xdf21fa922215b1a56f5a6d6294e6e36c85a0acfb","gasUsed":"0xbae2","logs":[{"address":"0xbb9bc244d798123fde783fcc1c72d3bb8c189413","topics":["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef","0x000000000000000000000000df21fa922215b1a56f5a6d6294e6e36c85a0acfb","0x00000000000000000000000032be343b94f860124dc4fee278fdcbd38c102d88"],"data":"0x0000000000000000000000000000000000000000000000027cfefc4f3f392700","blockNumber":"0x1e773b","transactionIndex":"0x1","transactionHash":"0x0b4cc7844537023b709953390e3881ec5b233703a8e8824dc03e13729a1bd95a","blockHash":"0xad20a0f78d19d7857067a9c06e6411efeab7673e183e4a545f53b724bb7fabf0","logIndex":"0x0"}],"logsBloom":"0x00000000000000020000000000020000000000000000000000000000000000000000000000000000000000000000000000040000000000000100000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000000000000000000000000000800000010000000000000000000000000000000000000000000000010000000000000000000001000000000000000000000000000000000000000000000000000000000000000000000002002000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000","root":"0x6e8a06b2dac39ac5c9d4db5fb2a2a94ef7a6e5ec1c554079112112caf162998a","to":"0xbb9bc244d798123fde783fcc1c72d3bb8c189413","transactionHash":"0x0b4cc7844537023b709953390e3881ec5b233703a8e8824dc03e13729a1bd95a","transactionIndex":"0x1"}`,
+	},
+	"missing post state": {
+		input:     `{"blockHash":"0xad20a0f78d19d7857067a9c06e6411efeab7673e183e4a545f53b724bb7fabf0","blockNumber":"0x1e773b","contractAddress":null,"cumulativeGasUsed":"0x10cea","from":"0xdf21fa922215b1a56f5a6d6294e6e36c85a0acfb","gasUsed":"0xbae2","logs":[{"address":"0xbb9bc244d798123fde783fcc1c72d3bb8c189413","topics":["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef","0x000000000000000000000000df21fa922215b1a56f5a6d6294e6e36c85a0acfb","0x00000000000000000000000032be343b94f860124dc4fee278fdcbd38c102d88"],"data":"0x0000000000000000000000000000000000000000000000027cfefc4f3f392700","blockNumber":"0x1e773b","transactionIndex":"0x1","transactionHash":"0x0b4cc7844537023b709953390e3881ec5b233703a8e8824dc03e13729a1bd95a","blockHash":"0xad20a0f78d19d7857067a9c06e6411efeab7673e183e4a545f53b724bb7fabf0","logIndex":"0x0"}],"logsBloom":"0x00000000000000020000000000020000000000000000000000000000000000000000000000000000000000000000000000040000000000000100000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000000000000000000000000000800000010000000000000000000000000000000000000000000000010000000000000000000001000000000000000000000000000000000000000000000000000000000000000000000002002000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000","to":"0xbb9bc244d798123fde783fcc1c72d3bb8c189413","transactionHash":"0x0b4cc7844537023b709953390e3881ec5b233703a8e8824dc03e13729a1bd95a","transactionIndex":"0x1"}`,
+		wantError: errMissingReceiptPostState,
+	},
+	"missing fields": {
+		input:     `{"blockHash":"0xad20a0f78d19d7857067a9c06e6411efeab7673e183e4a545f53b724bb7fabf0","blockNumber":"0x1e773b","contractAddress":null,"cumulativeGasUsed":"0x10cea","from":"0xdf21fa922215b1a56f5a6d6294e6e36c85a0acfb","gasUsed":"0xbae2","logs":[{"address":"0xbb9bc244d798123fde783fcc1c72d3bb8c189413","topics":["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef","0x000000000000000000000000df21fa922215b1a56f5a6d6294e6e36c85a0acfb","0x00000000000000000000000032be343b94f860124dc4fee278fdcbd38c102d88"],"data":"0x0000000000000000000000000000000000000000000000027cfefc4f3f392700","blockNumber":"0x1e773b","transactionIndex":"0x1","transactionHash":"0x0b4cc7844537023b709953390e3881ec5b233703a8e8824dc03e13729a1bd95a","blockHash":"0xad20a0f78d19d7857067a9c06e6411efeab7673e183e4a545f53b724bb7fabf0","logIndex":"0x0"}],"logsBloom":"0x00000000000000020000000000020000000000000000000000000000000000000000000000000000000000000000000000040000000000000100000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000000000000000000000000000800000010000000000000000000000000000000000000000000000010000000000000000000001000000000000000000000000000000000000000000000000000000000000000000000002002000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000","root":"0x6e8a06b2dac39ac5c9d4db5fb2a2a94ef7a6e5ec1c554079112112caf162998a","to":"0xbb9bc244d798123fde783fcc1c72d3bb8c189413"}`,
+		wantError: errMissingReceiptFields,
+	},
+}
+
+func TestUnmarshalReceipt(t *testing.T) {
+	for name, test := range unmarshalReceiptTests {
+		var r *Receipt
+		err := json.Unmarshal([]byte(test.input), &r)
+		checkError(t, name, err, test.wantError)
+	}
+}
+
+func checkError(t *testing.T, testname string, got, want error) bool {
+	if got == nil {
+		if want != nil {
+			t.Errorf("test %q: got no error, want %q", testname, want)
+			return false
+		}
+		return true
+	}
+	if want == nil {
+		t.Errorf("test %q: unexpected error %q", testname, got)
+	} else if got.Error() != want.Error() {
+		t.Errorf("test %q: got error %q, want %q", testname, got, want)
+	}
+	return false
+}
diff --git a/core/types/receipt.go b/core/types/receipt.go
index 5f847fc5c..9f820eb18 100644
--- a/core/types/receipt.go
+++ b/core/types/receipt.go
@@ -17,6 +17,8 @@
 package types
 
 import (
+	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"math/big"
@@ -26,6 +28,11 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
+var (
+	errMissingReceiptPostState = errors.New("missing post state root in JSON receipt")
+	errMissingReceiptFields    = errors.New("missing required JSON receipt fields")
+)
+
 // Receipt represents the results of a transaction.
 type Receipt struct {
 	// Consensus fields
@@ -34,12 +41,22 @@ type Receipt struct {
 	Bloom             Bloom
 	Logs              vm.Logs
 
-	// Implementation fields
+	// Implementation fields (don't reorder!)
 	TxHash          common.Hash
 	ContractAddress common.Address
 	GasUsed         *big.Int
 }
 
+type jsonReceipt struct {
+	PostState         *common.Hash    `json:"root"`
+	CumulativeGasUsed *hexBig         `json:"cumulativeGasUsed"`
+	Bloom             *Bloom          `json:"logsBloom"`
+	Logs              *vm.Logs        `json:"logs"`
+	TxHash            *common.Hash    `json:"transactionHash"`
+	ContractAddress   *common.Address `json:"contractAddress"`
+	GasUsed           *hexBig         `json:"gasUsed"`
+}
+
 // NewReceipt creates a barebone transaction receipt, copying the init fields.
 func NewReceipt(root []byte, cumulativeGasUsed *big.Int) *Receipt {
 	return &Receipt{PostState: common.CopyBytes(root), CumulativeGasUsed: new(big.Int).Set(cumulativeGasUsed)}
@@ -67,13 +84,34 @@ func (r *Receipt) DecodeRLP(s *rlp.Stream) error {
 	return nil
 }
 
-// RlpEncode implements common.RlpEncode required for SHA3 derivation.
-func (r *Receipt) RlpEncode() []byte {
-	bytes, err := rlp.EncodeToBytes(r)
-	if err != nil {
-		panic(err)
+// UnmarshalJSON decodes the web3 RPC receipt format.
+func (r *Receipt) UnmarshalJSON(input []byte) error {
+	var dec jsonReceipt
+	if err := json.Unmarshal(input, &dec); err != nil {
+		return err
 	}
-	return bytes
+	// Ensure that all fields are set. PostState is checked separately because it is a
+	// recent addition to the RPC spec (as of August 2016) and older implementations might
+	// not provide it. Note that ContractAddress is not checked because it can be null.
+	if dec.PostState == nil {
+		return errMissingReceiptPostState
+	}
+	if dec.CumulativeGasUsed == nil || dec.Bloom == nil ||
+		dec.Logs == nil || dec.TxHash == nil || dec.GasUsed == nil {
+		return errMissingReceiptFields
+	}
+	*r = Receipt{
+		PostState:         (*dec.PostState)[:],
+		CumulativeGasUsed: (*big.Int)(dec.CumulativeGasUsed),
+		Bloom:             *dec.Bloom,
+		Logs:              *dec.Logs,
+		TxHash:            *dec.TxHash,
+		GasUsed:           (*big.Int)(dec.GasUsed),
+	}
+	if dec.ContractAddress != nil {
+		r.ContractAddress = *dec.ContractAddress
+	}
+	return nil
 }
 
 // String implements the Stringer interface.
@@ -122,7 +160,7 @@ func (r *ReceiptForStorage) DecodeRLP(s *rlp.Stream) error {
 	return nil
 }
 
-// Receipts is a wrapper around a Receipt array to implement types.DerivableList.
+// Receipts is a wrapper around a Receipt array to implement DerivableList.
 type Receipts []*Receipt
 
 // Len returns the number of receipts in this list.
diff --git a/core/types/transaction.go b/core/types/transaction.go
index c71c98aa7..d369d7772 100644
--- a/core/types/transaction.go
+++ b/core/types/transaction.go
@@ -19,6 +19,7 @@ package types
 import (
 	"container/heap"
 	"crypto/ecdsa"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -28,12 +29,15 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/ethereum/go-ethereum/logger"
-	"github.com/ethereum/go-ethereum/logger/glog"
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
-var ErrInvalidSig = errors.New("invalid v, r, s values")
+var ErrInvalidSig = errors.New("invalid transaction v, r, s values")
+
+var (
+	errMissingTxSignatureFields = errors.New("missing required JSON transaction signature fields")
+	errMissingTxFields          = errors.New("missing required JSON transaction fields")
+)
 
 type Transaction struct {
 	data txdata
@@ -53,6 +57,20 @@ type txdata struct {
 	R, S            *big.Int // signature
 }
 
+type jsonTransaction struct {
+	Hash         *common.Hash    `json:"hash"`
+	AccountNonce *hexUint64      `json:"nonce"`
+	Price        *hexBig         `json:"gasPrice"`
+	GasLimit     *hexBig         `json:"gas"`
+	Recipient    *common.Address `json:"to"`
+	Amount       *hexBig         `json:"value"`
+	Payload      *hexBytes       `json:"input"`
+	V            *hexUint64      `json:"v"`
+	R            *hexBig         `json:"r"`
+	S            *hexBig         `json:"s"`
+}
+
+// NewContractCreation creates a new transaction with no recipient.
 func NewContractCreation(nonce uint64, amount, gasLimit, gasPrice *big.Int, data []byte) *Transaction {
 	if len(data) > 0 {
 		data = common.CopyBytes(data)
@@ -69,6 +87,7 @@ func NewContractCreation(nonce uint64, amount, gasLimit, gasPrice *big.Int, data
 	}}
 }
 
+// NewTransaction creates a new transaction with the given fields.
 func NewTransaction(nonce uint64, to common.Address, amount, gasLimit, gasPrice *big.Int, data []byte) *Transaction {
 	if len(data) > 0 {
 		data = common.CopyBytes(data)
@@ -95,10 +114,12 @@ func NewTransaction(nonce uint64, to common.Address, amount, gasLimit, gasPrice
 	return &Transaction{data: d}
 }
 
+// DecodeRLP implements rlp.Encoder
 func (tx *Transaction) EncodeRLP(w io.Writer) error {
 	return rlp.Encode(w, &tx.data)
 }
 
+// DecodeRLP implements rlp.Decoder
 func (tx *Transaction) DecodeRLP(s *rlp.Stream) error {
 	_, size, _ := s.Kind()
 	err := s.Decode(&tx.data)
@@ -108,6 +129,42 @@ func (tx *Transaction) DecodeRLP(s *rlp.Stream) error {
 	return err
 }
 
+// UnmarshalJSON decodes the web3 RPC transaction format.
+func (tx *Transaction) UnmarshalJSON(input []byte) error {
+	var dec jsonTransaction
+	if err := json.Unmarshal(input, &dec); err != nil {
+		return err
+	}
+	// Ensure that all fields are set. V, R, S are checked separately because they're a
+	// recent addition to the RPC spec (as of August 2016) and older implementations might
+	// not provide them. Note that Recipient is not checked because it can be missing for
+	// contract creations.
+	if dec.V == nil || dec.R == nil || dec.S == nil {
+		return errMissingTxSignatureFields
+	}
+	if !crypto.ValidateSignatureValues(byte(*dec.V), (*big.Int)(dec.R), (*big.Int)(dec.S), false) {
+		return ErrInvalidSig
+	}
+	if dec.AccountNonce == nil || dec.Price == nil || dec.GasLimit == nil || dec.Amount == nil || dec.Payload == nil {
+		return errMissingTxFields
+	}
+	// Assign the fields. This is not atomic but reusing transactions
+	// for decoding isn't thread safe anyway.
+	*tx = Transaction{}
+	tx.data = txdata{
+		AccountNonce: uint64(*dec.AccountNonce),
+		Recipient:    dec.Recipient,
+		Amount:       (*big.Int)(dec.Amount),
+		GasLimit:     (*big.Int)(dec.GasLimit),
+		Price:        (*big.Int)(dec.Price),
+		Payload:      *dec.Payload,
+		V:            byte(*dec.V),
+		R:            (*big.Int)(dec.R),
+		S:            (*big.Int)(dec.S),
+	}
+	return nil
+}
+
 func (tx *Transaction) Data() []byte       { return common.CopyBytes(tx.data.Payload) }
 func (tx *Transaction) Gas() *big.Int      { return new(big.Int).Set(tx.data.GasLimit) }
 func (tx *Transaction) GasPrice() *big.Int { return new(big.Int).Set(tx.data.Price) }
@@ -215,6 +272,7 @@ func (tx *Transaction) Cost() *big.Int {
 	return total
 }
 
+// SignatureValues returns the ECDSA signature values contained in the transaction.
 func (tx *Transaction) SignatureValues() (v byte, r *big.Int, s *big.Int) {
 	return tx.data.V, new(big.Int).Set(tx.data.R), new(big.Int).Set(tx.data.S)
 }
@@ -235,7 +293,6 @@ func (tx *Transaction) publicKey(homestead bool) ([]byte, error) {
 	hash := tx.SigHash()
 	pub, err := crypto.Ecrecover(hash[:], sig)
 	if err != nil {
-		glog.V(logger.Error).Infof("Could not get pubkey from signature: ", err)
 		return nil, err
 	}
 	if len(pub) == 0 || pub[0] != 4 {
diff --git a/core/vm/log.go b/core/vm/log.go
index e4cc6021b..b292f5f43 100644
--- a/core/vm/log.go
+++ b/core/vm/log.go
@@ -18,6 +18,7 @@ package vm
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 
@@ -25,18 +26,33 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
+var errMissingLogFields = errors.New("missing required JSON log fields")
+
+// Log represents a contract log event. These events are generated by the LOG
+// opcode and stored/indexed by the node.
 type Log struct {
-	// Consensus fields
-	Address common.Address
-	Topics  []common.Hash
-	Data    []byte
+	// Consensus fields.
+	Address common.Address // address of the contract that generated the event
+	Topics  []common.Hash  // list of topics provided by the contract.
+	Data    []byte         // supplied by the contract, usually ABI-encoded
+
+	// Derived fields (don't reorder!).
+	BlockNumber uint64      // block in which the transaction was included
+	TxHash      common.Hash // hash of the transaction
+	TxIndex     uint        // index of the transaction in the block
+	BlockHash   common.Hash // hash of the block in which the transaction was included
+	Index       uint        // index of the log in the receipt
+}
 
-	// Derived fields (don't reorder!)
-	BlockNumber uint64
-	TxHash      common.Hash
-	TxIndex     uint
-	BlockHash   common.Hash
-	Index       uint
+type jsonLog struct {
+	Address     *common.Address `json:"address"`
+	Topics      *[]common.Hash  `json:"topics"`
+	Data        string          `json:"data"`
+	BlockNumber string          `json:"blockNumber"`
+	TxIndex     string          `json:"transactionIndex"`
+	TxHash      *common.Hash    `json:"transactionHash"`
+	BlockHash   *common.Hash    `json:"blockHash"`
+	Index       string          `json:"logIndex"`
 }
 
 func NewLog(address common.Address, topics []common.Hash, data []byte, number uint64) *Log {
@@ -64,19 +80,50 @@ func (l *Log) String() string {
 	return fmt.Sprintf(`log: %x %x %x %x %d %x %d`, l.Address, l.Topics, l.Data, l.TxHash, l.TxIndex, l.BlockHash, l.Index)
 }
 
+// MarshalJSON implements json.Marshaler.
 func (r *Log) MarshalJSON() ([]byte, error) {
-	fields := map[string]interface{}{
-		"address":          r.Address,
-		"data":             fmt.Sprintf("%#x", r.Data),
-		"blockNumber":      fmt.Sprintf("%#x", r.BlockNumber),
-		"logIndex":         fmt.Sprintf("%#x", r.Index),
-		"blockHash":        r.BlockHash,
-		"transactionHash":  r.TxHash,
-		"transactionIndex": fmt.Sprintf("%#x", r.TxIndex),
-		"topics":           r.Topics,
-	}
+	return json.Marshal(&jsonLog{
+		Address:     &r.Address,
+		Topics:      &r.Topics,
+		Data:        fmt.Sprintf("0x%x", r.Data),
+		BlockNumber: fmt.Sprintf("0x%x", r.BlockNumber),
+		TxIndex:     fmt.Sprintf("0x%x", r.TxIndex),
+		TxHash:      &r.TxHash,
+		BlockHash:   &r.BlockHash,
+		Index:       fmt.Sprintf("0x%x", r.Index),
+	})
+}
 
-	return json.Marshal(fields)
+// UnmarshalJSON implements json.Umarshaler.
+func (r *Log) UnmarshalJSON(input []byte) error {
+	var dec jsonLog
+	if err := json.Unmarshal(input, &dec); err != nil {
+		return err
+	}
+	if dec.Address == nil || dec.Topics == nil || dec.Data == "" || dec.BlockNumber == "" ||
+		dec.TxIndex == "" || dec.TxHash == nil || dec.BlockHash == nil || dec.Index == "" {
+		return errMissingLogFields
+	}
+	declog := Log{
+		Address:   *dec.Address,
+		Topics:    *dec.Topics,
+		TxHash:    *dec.TxHash,
+		BlockHash: *dec.BlockHash,
+	}
+	if _, err := fmt.Sscanf(dec.Data, "0x%x", &declog.Data); err != nil {
+		return fmt.Errorf("invalid hex log data")
+	}
+	if _, err := fmt.Sscanf(dec.BlockNumber, "0x%x", &declog.BlockNumber); err != nil {
+		return fmt.Errorf("invalid hex log block number")
+	}
+	if _, err := fmt.Sscanf(dec.TxIndex, "0x%x", &declog.TxIndex); err != nil {
+		return fmt.Errorf("invalid hex log tx index")
+	}
+	if _, err := fmt.Sscanf(dec.Index, "0x%x", &declog.Index); err != nil {
+		return fmt.Errorf("invalid hex log index")
+	}
+	*r = declog
+	return nil
 }
 
 type Logs []*Log
diff --git a/core/vm/log_test.go b/core/vm/log_test.go
new file mode 100644
index 000000000..775016f9c
--- /dev/null
+++ b/core/vm/log_test.go
@@ -0,0 +1,59 @@
+// Copyright 2016 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 vm
+
+import (
+	"encoding/json"
+	"testing"
+)
+
+var unmarshalLogTests = map[string]struct {
+	input     string
+	wantError error
+}{
+	"ok": {
+		input: `{"address":"0xecf8f87f810ecf450940c9f60066b4a7a501d6a7","blockHash":"0x656c34545f90a730a19008c0e7a7cd4fb3895064b48d6d69761bd5abad681056","blockNumber":"0x1ecfa4","data":"0x000000000000000000000000000000000000000000000001a055690d9db80000","logIndex":"0x2","topics":["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef","0x00000000000000000000000080b2c9d7cbbf30a1b0fc8983c647d754c6525615","0x000000000000000000000000f9dff387dcb5cc4cca5b91adb07a95f54e9f1bb6"],"transactionHash":"0x3b198bfd5d2907285af009e9ae84a0ecd63677110d89d7e030251acb87f6487e","transactionIndex":"0x3"}`,
+	},
+	"missing data": {
+		input:     `{"address":"0xecf8f87f810ecf450940c9f60066b4a7a501d6a7","blockHash":"0x656c34545f90a730a19008c0e7a7cd4fb3895064b48d6d69761bd5abad681056","blockNumber":"0x1ecfa4","logIndex":"0x2","topics":["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef","0x00000000000000000000000080b2c9d7cbbf30a1b0fc8983c647d754c6525615","0x000000000000000000000000f9dff387dcb5cc4cca5b91adb07a95f54e9f1bb6"],"transactionHash":"0x3b198bfd5d2907285af009e9ae84a0ecd63677110d89d7e030251acb87f6487e","transactionIndex":"0x3"}`,
+		wantError: errMissingLogFields,
+	},
+}
+
+func TestUnmarshalLog(t *testing.T) {
+	for name, test := range unmarshalLogTests {
+		var log *Log
+		err := json.Unmarshal([]byte(test.input), &log)
+		checkError(t, name, err, test.wantError)
+	}
+}
+
+func checkError(t *testing.T, testname string, got, want error) bool {
+	if got == nil {
+		if want != nil {
+			t.Errorf("test %q: got no error, want %q", testname, want)
+			return false
+		}
+		return true
+	}
+	if want == nil {
+		t.Errorf("test %q: unexpected error %q", testname, got)
+	} else if got.Error() != want.Error() {
+		t.Errorf("test %q: got error %q, want %q", testname, got, want)
+	}
+	return false
+}
diff --git a/eth/bind.go b/eth/bind.go
index bf7a7fb53..532e94460 100644
--- a/eth/bind.go
+++ b/eth/bind.go
@@ -19,6 +19,7 @@ package eth
 import (
 	"math/big"
 
+	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/internal/ethapi"
@@ -50,47 +51,62 @@ func NewContractBackend(eth *Ethereum) *ContractBackend {
 	}
 }
 
-// HasCode implements bind.ContractVerifier.HasCode by retrieving any code associated
-// with the contract from the local API, and checking its size.
-func (b *ContractBackend) HasCode(ctx context.Context, contract common.Address, pending bool) (bool, error) {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	block := rpc.LatestBlockNumber
-	if pending {
-		block = rpc.PendingBlockNumber
-	}
-	out, err := b.bcapi.GetCode(ctx, contract, block)
-	return len(common.FromHex(out)) > 0, err
+// CodeAt retrieves any code associated with the contract from the local API.
+func (b *ContractBackend) CodeAt(ctx context.Context, contract common.Address, blockNum *big.Int) ([]byte, error) {
+	out, err := b.bcapi.GetCode(ctx, contract, toBlockNumber(blockNum))
+	return common.FromHex(out), err
+}
+
+// CodeAt retrieves any code associated with the contract from the local API.
+func (b *ContractBackend) PendingCodeAt(ctx context.Context, contract common.Address) ([]byte, error) {
+	out, err := b.bcapi.GetCode(ctx, contract, rpc.PendingBlockNumber)
+	return common.FromHex(out), err
 }
 
 // ContractCall implements bind.ContractCaller executing an Ethereum contract
 // call with the specified data as the input. The pending flag requests execution
 // against the pending block, not the stable head of the chain.
-func (b *ContractBackend) ContractCall(ctx context.Context, contract common.Address, data []byte, pending bool) ([]byte, error) {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	// Convert the input args to the API spec
+func (b *ContractBackend) CallContract(ctx context.Context, msg ethereum.CallMsg, blockNum *big.Int) ([]byte, error) {
+	out, err := b.bcapi.Call(ctx, toCallArgs(msg), toBlockNumber(blockNum))
+	return common.FromHex(out), err
+}
+
+// ContractCall implements bind.ContractCaller executing an Ethereum contract
+// call with the specified data as the input. The pending flag requests execution
+// against the pending block, not the stable head of the chain.
+func (b *ContractBackend) PendingCallContract(ctx context.Context, msg ethereum.CallMsg) ([]byte, error) {
+	out, err := b.bcapi.Call(ctx, toCallArgs(msg), rpc.PendingBlockNumber)
+	return common.FromHex(out), err
+}
+
+func toCallArgs(msg ethereum.CallMsg) ethapi.CallArgs {
 	args := ethapi.CallArgs{
-		To:   &contract,
-		Data: common.ToHex(data),
+		To:   msg.To,
+		From: msg.From,
+		Data: common.ToHex(msg.Data),
 	}
-	block := rpc.LatestBlockNumber
-	if pending {
-		block = rpc.PendingBlockNumber
+	if msg.Gas != nil {
+		args.Gas = *rpc.NewHexNumber(msg.Gas)
 	}
-	// Execute the call and convert the output back to Go types
-	out, err := b.bcapi.Call(ctx, args, block)
-	return common.FromHex(out), err
+	if msg.GasPrice != nil {
+		args.GasPrice = *rpc.NewHexNumber(msg.GasPrice)
+	}
+	if msg.Value != nil {
+		args.Value = *rpc.NewHexNumber(msg.Value)
+	}
+	return args
+}
+
+func toBlockNumber(num *big.Int) rpc.BlockNumber {
+	if num == nil {
+		return rpc.LatestBlockNumber
+	}
+	return rpc.BlockNumber(num.Int64())
 }
 
 // PendingAccountNonce implements bind.ContractTransactor retrieving the current
 // pending nonce associated with an account.
-func (b *ContractBackend) PendingAccountNonce(ctx context.Context, account common.Address) (uint64, error) {
-	if ctx == nil {
-		ctx = context.Background()
-	}
+func (b *ContractBackend) PendingNonceAt(ctx context.Context, account common.Address) (uint64, error) {
 	out, err := b.txapi.GetTransactionCount(ctx, account, rpc.PendingBlockNumber)
 	return out.Uint64(), err
 }
@@ -98,9 +114,6 @@ func (b *ContractBackend) PendingAccountNonce(ctx context.Context, account commo
 // SuggestGasPrice implements bind.ContractTransactor retrieving the currently
 // suggested gas price to allow a timely execution of a transaction.
 func (b *ContractBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error) {
-	if ctx == nil {
-		ctx = context.Background()
-	}
 	return b.eapi.GasPrice(ctx)
 }
 
@@ -109,25 +122,14 @@ func (b *ContractBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error)
 // the backend blockchain. There is no guarantee that this is the true gas limit
 // requirement as other transactions may be added or removed by miners, but it
 // should provide a basis for setting a reasonable default.
-func (b *ContractBackend) EstimateGasLimit(ctx context.Context, sender common.Address, contract *common.Address, value *big.Int, data []byte) (*big.Int, error) {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	out, err := b.bcapi.EstimateGas(ctx, ethapi.CallArgs{
-		From:  sender,
-		To:    contract,
-		Value: *rpc.NewHexNumber(value),
-		Data:  common.ToHex(data),
-	})
+func (b *ContractBackend) EstimateGas(ctx context.Context, msg ethereum.CallMsg) (*big.Int, error) {
+	out, err := b.bcapi.EstimateGas(ctx, toCallArgs(msg))
 	return out.BigInt(), err
 }
 
 // SendTransaction implements bind.ContractTransactor injects the transaction
 // into the pending pool for execution.
 func (b *ContractBackend) SendTransaction(ctx context.Context, tx *types.Transaction) error {
-	if ctx == nil {
-		ctx = context.Background()
-	}
 	raw, _ := rlp.EncodeToBytes(tx)
 	_, err := b.txapi.SendRawTransaction(ctx, common.ToHex(raw))
 	return err
diff --git a/eth/handler.go b/eth/handler.go
index 886d89fd1..570c79dac 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -634,9 +634,6 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 		if err := msg.Decode(&request); err != nil {
 			return errResp(ErrDecode, "%v: %v", msg, err)
 		}
-		if err := request.Block.ValidateFields(); err != nil {
-			return errResp(ErrDecode, "block validation %v: %v", msg, err)
-		}
 		request.Block.ReceivedAt = msg.ReceivedAt
 		request.Block.ReceivedFrom = p
 
diff --git a/ethclient/ethclient.go b/ethclient/ethclient.go
new file mode 100644
index 000000000..575a7cb44
--- /dev/null
+++ b/ethclient/ethclient.go
@@ -0,0 +1,382 @@
+// Copyright 2016 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 ethclient provides a client for the Ethereum RPC API.
+package ethclient
+
+import (
+	"encoding/json"
+	"fmt"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
+	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/ethereum/go-ethereum/rpc"
+	"golang.org/x/net/context"
+)
+
+// Client defines typed wrappers for the Ethereum RPC API.
+type Client struct {
+	c *rpc.Client
+}
+
+// Dial connects a client to the given URL.
+func Dial(rawurl string) (*Client, error) {
+	c, err := rpc.Dial(rawurl)
+	if err != nil {
+		return nil, err
+	}
+	return NewClient(c), nil
+}
+
+// NewClient creates a client that uses the given RPC client.
+func NewClient(c *rpc.Client) *Client {
+	return &Client{c}
+}
+
+// Blockchain Access
+
+// BlockByHash returns the given full block.
+//
+// Note that loading full blocks requires two requests. Use HeaderByHash
+// if you don't need all transactions or uncle headers.
+func (ec *Client) BlockByHash(ctx context.Context, hash common.Hash) (*types.Block, error) {
+	return ec.getBlock(ctx, "eth_getBlockByHash", hash, true)
+}
+
+// BlockByNumber returns a block from the current canonical chain. If number is nil, the
+// latest known block is returned.
+//
+// Note that loading full blocks requires two requests. Use HeaderByNumber
+// if you don't need all transactions or uncle headers.
+func (ec *Client) BlockByNumber(ctx context.Context, number *big.Int) (*types.Block, error) {
+	return ec.getBlock(ctx, "eth_getBlockByNumber", toBlockNumArg(number), true)
+}
+
+type rpcBlock struct {
+	Hash         common.Hash          `json:"hash"`
+	Transactions []*types.Transaction `json:"transactions"`
+	UncleHashes  []common.Hash        `json:"uncles"`
+}
+
+func (ec *Client) getBlock(ctx context.Context, method string, args ...interface{}) (*types.Block, error) {
+	var raw json.RawMessage
+	err := ec.c.CallContext(ctx, &raw, method, args...)
+	if err != nil {
+		return nil, err
+	}
+	// Decode header and transactions.
+	var head *types.Header
+	var body rpcBlock
+	if err := json.Unmarshal(raw, &head); err != nil {
+		return nil, err
+	}
+	if err := json.Unmarshal(raw, &body); err != nil {
+		return nil, err
+	}
+	// Quick-verify transaction and uncle lists. This mostly helps with debugging the server.
+	if head.UncleHash == types.EmptyUncleHash && len(body.UncleHashes) > 0 {
+		return nil, fmt.Errorf("server returned non-empty uncle list but block header indicates no uncles")
+	}
+	if head.UncleHash != types.EmptyUncleHash && len(body.UncleHashes) == 0 {
+		return nil, fmt.Errorf("server returned empty uncle list but block header indicates uncles")
+	}
+	if head.TxHash == types.EmptyRootHash && len(body.Transactions) > 0 {
+		return nil, fmt.Errorf("server returned non-empty transaction list but block header indicates no transactions")
+	}
+	if head.TxHash != types.EmptyRootHash && len(body.Transactions) == 0 {
+		return nil, fmt.Errorf("server returned empty transaction list but block header indicates transactions")
+	}
+	// Load uncles because they are not included in the block response.
+	var uncles []*types.Header
+	if len(body.UncleHashes) > 0 {
+		uncles = make([]*types.Header, len(body.UncleHashes))
+		reqs := make([]rpc.BatchElem, len(body.UncleHashes))
+		for i := range reqs {
+			reqs[i] = rpc.BatchElem{
+				Method: "eth_getUncleByBlockHashAndIndex",
+				Args:   []interface{}{body.Hash, fmt.Sprintf("%#x", i)},
+				Result: &uncles[i],
+			}
+		}
+		if err := ec.c.BatchCallContext(ctx, reqs); err != nil {
+			return nil, err
+		}
+		for i := range reqs {
+			if reqs[i].Error != nil {
+				return nil, reqs[i].Error
+			}
+		}
+	}
+	return types.NewBlockWithHeader(head).WithBody(body.Transactions, uncles), nil
+}
+
+// HeaderByHash returns the block header with the given hash.
+func (ec *Client) HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error) {
+	var head *types.Header
+	err := ec.c.CallContext(ctx, &head, "eth_getBlockByHash", hash, false)
+	return head, err
+}
+
+// HeaderByNumber returns a block header from the current canonical chain. If number is
+// nil, the latest known header is returned.
+func (ec *Client) HeaderByNumber(ctx context.Context, number *big.Int) (*types.Header, error) {
+	var head *types.Header
+	err := ec.c.CallContext(ctx, &head, "eth_getBlockByNumber", toBlockNumArg(number), false)
+	return head, err
+}
+
+// TransactionByHash returns the transaction with the given hash.
+func (ec *Client) TransactionByHash(ctx context.Context, hash common.Hash) (*types.Transaction, error) {
+	var tx *types.Transaction
+	err := ec.c.CallContext(ctx, &tx, "eth_getTransactionByHash", hash, false)
+	if err == nil {
+		if _, r, _ := tx.SignatureValues(); r == nil {
+			return nil, fmt.Errorf("server returned transaction without signature")
+		}
+	}
+	return tx, err
+}
+
+// TransactionCount returns the total number of transactions in the given block.
+func (ec *Client) TransactionCount(ctx context.Context, blockHash common.Hash) (uint, error) {
+	var num rpc.HexNumber
+	err := ec.c.CallContext(ctx, &num, "eth_getBlockTransactionCountByHash", blockHash)
+	return num.Uint(), err
+}
+
+// TransactionInBlock returns a single transaction at index in the given block.
+func (ec *Client) TransactionInBlock(ctx context.Context, blockHash common.Hash, index uint) (*types.Transaction, error) {
+	var tx *types.Transaction
+	err := ec.c.CallContext(ctx, &tx, "eth_getTransactionByBlockHashAndIndex", blockHash, index)
+	if err == nil {
+		if _, r, _ := tx.SignatureValues(); r == nil {
+			return nil, fmt.Errorf("server returned transaction without signature")
+		}
+	}
+	return tx, err
+}
+
+// TransactionReceipt returns the receipt of a transaction by transaction hash.
+// Note that the receipt is not available for pending transactions.
+func (ec *Client) TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error) {
+	var r *types.Receipt
+	err := ec.c.CallContext(ctx, &r, "eth_getTransactionReceipt", txHash)
+	if err == nil && r != nil && len(r.PostState) == 0 {
+		return nil, fmt.Errorf("server returned receipt without post state")
+	}
+	return r, err
+}
+
+func toBlockNumArg(number *big.Int) string {
+	if number == nil {
+		return "latest"
+	}
+	return fmt.Sprintf("%#x", number)
+}
+
+// SubscribeNewHead subscribes to notifications about the current blockchain head
+// on the given channel.
+func (ec *Client) SubscribeNewHead(ctx context.Context, ch chan<- *types.Header) (ethereum.Subscription, error) {
+	return ec.c.EthSubscribe(ctx, ch, "newBlocks", map[string]struct{}{})
+}
+
+// State Access
+
+// BalanceAt returns the wei balance of the given account.
+// The block number can be nil, in which case the balance is taken from the latest known block.
+func (ec *Client) BalanceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (*big.Int, error) {
+	var result rpc.HexNumber
+	err := ec.c.CallContext(ctx, &result, "eth_getBalance", account, toBlockNumArg(blockNumber))
+	return (*big.Int)(&result), err
+}
+
+// StorageAt returns the value of key in the contract storage of the given account.
+// The block number can be nil, in which case the value is taken from the latest known block.
+func (ec *Client) StorageAt(ctx context.Context, account common.Address, key common.Hash, blockNumber *big.Int) ([]byte, error) {
+	var result rpc.HexBytes
+	err := ec.c.CallContext(ctx, &result, "eth_getStorageAt", account, key, toBlockNumArg(blockNumber))
+	return result, err
+}
+
+// CodeAt returns the contract code of the given account.
+// The block number can be nil, in which case the code is taken from the latest known block.
+func (ec *Client) CodeAt(ctx context.Context, account common.Address, blockNumber *big.Int) ([]byte, error) {
+	var result rpc.HexBytes
+	err := ec.c.CallContext(ctx, &result, "eth_getCode", account, toBlockNumArg(blockNumber))
+	return result, err
+}
+
+// NonceAt returns the account nonce of the given account.
+// The block number can be nil, in which case the nonce is taken from the latest known block.
+func (ec *Client) NonceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (uint64, error) {
+	var result rpc.HexNumber
+	err := ec.c.CallContext(ctx, &result, "eth_getTransactionCount", account, toBlockNumArg(blockNumber))
+	return result.Uint64(), err
+}
+
+// Filters
+
+// FilterLogs executes a filter query.
+func (ec *Client) FilterLogs(ctx context.Context, q ethereum.FilterQuery) ([]vm.Log, error) {
+	var result []vm.Log
+	err := ec.c.CallContext(ctx, &result, "eth_getFilterLogs", toFilterArg(q))
+	return result, err
+}
+
+// SubscribeFilterLogs subscribes to the results of a streaming filter query.
+func (ec *Client) SubscribeFilterLogs(ctx context.Context, q ethereum.FilterQuery, ch chan<- vm.Log) (ethereum.Subscription, error) {
+	return ec.c.EthSubscribe(ctx, ch, "logs", toFilterArg(q))
+}
+
+func toFilterArg(q ethereum.FilterQuery) interface{} {
+	arg := map[string]interface{}{
+		"fromBlock": toBlockNumArg(q.FromBlock),
+		"endBlock":  toBlockNumArg(q.ToBlock),
+		"addresses": q.Addresses,
+		"topics":    q.Topics,
+	}
+	if q.FromBlock == nil {
+		arg["fromBlock"] = "0x0"
+	}
+	return arg
+}
+
+// Pending State
+
+// PendingBalanceAt returns the wei balance of the given account in the pending state.
+func (ec *Client) PendingBalanceAt(ctx context.Context, account common.Address) (*big.Int, error) {
+	var result rpc.HexNumber
+	err := ec.c.CallContext(ctx, &result, "eth_getBalance", account, "pending")
+	return (*big.Int)(&result), err
+}
+
+// PendingStorageAt returns the value of key in the contract storage of the given account in the pending state.
+func (ec *Client) PendingStorageAt(ctx context.Context, account common.Address, key common.Hash) ([]byte, error) {
+	var result rpc.HexBytes
+	err := ec.c.CallContext(ctx, &result, "eth_getStorageAt", account, key, "pending")
+	return result, err
+}
+
+// PendingCodeAt returns the contract code of the given account in the pending state.
+func (ec *Client) PendingCodeAt(ctx context.Context, account common.Address) ([]byte, error) {
+	var result rpc.HexBytes
+	err := ec.c.CallContext(ctx, &result, "eth_getCode", account, "pending")
+	return result, err
+}
+
+// PendingNonceAt returns the account nonce of the given account in the pending state.
+// This is the nonce that should be used for the next transaction.
+func (ec *Client) PendingNonceAt(ctx context.Context, account common.Address) (uint64, error) {
+	var result rpc.HexNumber
+	err := ec.c.CallContext(ctx, &result, "eth_getTransactionCount", account, "pending")
+	return result.Uint64(), err
+}
+
+// PendingTransactionCount returns the total number of transactions in the pending state.
+func (ec *Client) PendingTransactionCount(ctx context.Context) (uint, error) {
+	var num rpc.HexNumber
+	err := ec.c.CallContext(ctx, &num, "eth_getBlockTransactionCountByNumber", "pending")
+	return num.Uint(), err
+}
+
+// TODO: SubscribePendingTransactions (needs server side)
+
+// Contract Calling
+
+// CallContract executes a message call transaction, which is directly executed in the VM
+// of the node, but never mined into the blockchain.
+//
+// blockNumber selects the block height at which the call runs. It can be nil, in which
+// case the code is taken from the latest known block. Note that state from very old
+// blocks might not be available.
+func (ec *Client) CallContract(ctx context.Context, msg ethereum.CallMsg, blockNumber *big.Int) ([]byte, error) {
+	var hex string
+	err := ec.c.CallContext(ctx, &hex, "eth_call", toCallArg(msg), toBlockNumArg(blockNumber))
+	if err != nil {
+		return nil, err
+	}
+	return common.FromHex(hex), nil
+}
+
+// PendingCallContract executes a message call transaction using the EVM.
+// The state seen by the contract call is the pending state.
+func (ec *Client) PendingCallContract(ctx context.Context, msg ethereum.CallMsg) ([]byte, error) {
+	var hex string
+	err := ec.c.CallContext(ctx, &hex, "eth_call", toCallArg(msg), "pending")
+	if err != nil {
+		return nil, err
+	}
+	return common.FromHex(hex), nil
+}
+
+// SuggestGasPrice retrieves the currently suggested gas price to allow a timely
+// execution of a transaction.
+func (ec *Client) SuggestGasPrice(ctx context.Context) (*big.Int, error) {
+	var hex rpc.HexNumber
+	if err := ec.c.CallContext(ctx, &hex, "eth_gasPrice"); err != nil {
+		return nil, err
+	}
+	return (*big.Int)(&hex), nil
+}
+
+// EstimateGas tries to estimate the gas needed to execute a specific transaction based on
+// the current pending state of the backend blockchain. There is no guarantee that this is
+// the true gas limit requirement as other transactions may be added or removed by miners,
+// but it should provide a basis for setting a reasonable default.
+func (ec *Client) EstimateGas(ctx context.Context, msg ethereum.CallMsg) (*big.Int, error) {
+	var hex rpc.HexNumber
+	err := ec.c.CallContext(ctx, &hex, "eth_estimateGas", toCallArg(msg))
+	if err != nil {
+		return nil, err
+	}
+	return (*big.Int)(&hex), nil
+}
+
+// SendTransaction injects a signed transaction into the pending pool for execution.
+//
+// If the transaction was a contract creation use the TransactionReceipt method to get the
+// contract address after the transaction has been mined.
+func (ec *Client) SendTransaction(ctx context.Context, tx *types.Transaction) error {
+	data, err := rlp.EncodeToBytes(tx)
+	if err != nil {
+		return err
+	}
+	return ec.c.CallContext(ctx, nil, "eth_sendRawTransaction", common.ToHex(data))
+}
+
+func toCallArg(msg ethereum.CallMsg) interface{} {
+	arg := map[string]interface{}{
+		"from": msg.From,
+		"to":   msg.To,
+	}
+	if len(msg.Data) > 0 {
+		arg["data"] = fmt.Sprintf("%#x", msg.Data)
+	}
+	if msg.Value != nil {
+		arg["value"] = fmt.Sprintf("%#x", msg.Value)
+	}
+	if msg.Gas != nil {
+		arg["gas"] = fmt.Sprintf("%#x", msg.Gas)
+	}
+	if msg.GasPrice != nil {
+		arg["gasPrice"] = fmt.Sprintf("%#x", msg.GasPrice)
+	}
+	return arg
+}
diff --git a/ethclient/ethclient_test.go b/ethclient/ethclient_test.go
new file mode 100644
index 000000000..47e37c0ce
--- /dev/null
+++ b/ethclient/ethclient_test.go
@@ -0,0 +1,17 @@
+package ethclient
+
+import "github.com/ethereum/go-ethereum"
+
+// Verify that Client implements the ethereum interfaces.
+var (
+	_ = ethereum.ChainReader(&Client{})
+	_ = ethereum.ChainStateReader(&Client{})
+	_ = ethereum.ChainHeadEventer(&Client{})
+	_ = ethereum.ContractCaller(&Client{})
+	_ = ethereum.GasEstimator(&Client{})
+	_ = ethereum.GasPricer(&Client{})
+	_ = ethereum.LogFilterer(&Client{})
+	_ = ethereum.PendingStateReader(&Client{})
+	// _ = ethereum.PendingStateEventer(&Client{})
+	_ = ethereum.PendingContractCaller(&Client{})
+)
diff --git a/interfaces.go b/interfaces.go
new file mode 100644
index 000000000..921d02616
--- /dev/null
+++ b/interfaces.go
@@ -0,0 +1,168 @@
+// Copyright 2016 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 ethereum defines interfaces for interacting with Ethereum.
+package ethereum
+
+import (
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
+	"golang.org/x/net/context"
+)
+
+// TODO: move subscription to package event
+
+// Subscription represents an event subscription where events are
+// delivered on a data channel.
+type Subscription interface {
+	// Unsubscribe cancels the sending of events to the data channel
+	// and closes the error channel.
+	Unsubscribe()
+	// Err returns the subscription error channel. The error channel receives
+	// a value if there is an issue with the subscription (e.g. the network connection
+	// delivering the events has been closed). Only one value will ever be sent.
+	// The error channel is closed by Unsubscribe.
+	Err() <-chan error
+}
+
+// ChainReader provides access to the blockchain. The methods in this interface access raw
+// data from either the canonical chain (when requesting by block number) or any
+// blockchain fork that was previously downloaded and processed by the node. The block
+// number argument can be nil to select the latest canonical block. Reading block headers
+// should be preferred over full blocks whenever possible.
+type ChainReader interface {
+	BlockByHash(ctx context.Context, hash common.Hash) (*types.Block, error)
+	BlockByNumber(ctx context.Context, number *big.Int) (*types.Block, error)
+	HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error)
+	HeaderByNumber(ctx context.Context, number *big.Int) (*types.Header, error)
+	TransactionCount(ctx context.Context, blockHash common.Hash) (uint, error)
+	TransactionInBlock(ctx context.Context, blockHash common.Hash, index uint) (*types.Transaction, error)
+	TransactionByHash(ctx context.Context, txHash common.Hash) (*types.Transaction, error)
+	TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error)
+}
+
+// ChainStateReader wraps access to the state trie of the canonical blockchain. Note that
+// implementations of the interface may be unable to return state values for old blocks.
+// In many cases, using CallContract can be preferable to reading raw contract storage.
+type ChainStateReader interface {
+	BalanceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (*big.Int, error)
+	StorageAt(ctx context.Context, account common.Address, key common.Hash, blockNumber *big.Int) ([]byte, error)
+	CodeAt(ctx context.Context, account common.Address, blockNumber *big.Int) ([]byte, error)
+	NonceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (uint64, error)
+}
+
+// A ChainHeadEventer returns notifications whenever the canonical head block is updated.
+type ChainHeadEventer interface {
+	SubscribeNewHead(ctx context.Context, ch chan<- *types.Header) (Subscription, error)
+}
+
+// CallMsg contains parameters for contract calls.
+type CallMsg struct {
+	From     common.Address  // the sender of the 'transaction'
+	To       *common.Address // the destination contract (nil for contract creation)
+	Gas      *big.Int        // if nil, the call executes with near-infinite gas
+	GasPrice *big.Int        // wei <-> gas exchange ratio
+	Value    *big.Int        // amount of wei sent along with the call
+	Data     []byte          // input data, usually an ABI-encoded contract method invocation
+}
+
+// A ContractCaller provides contract calls, essentially transactions that are executed by
+// the EVM but not mined into the blockchain. ContractCall is a low-level method to
+// execute such calls. For applications which are structured around specific contracts,
+// the abigen tool provides a nicer, properly typed way to perform calls.
+type ContractCaller interface {
+	CallContract(ctx context.Context, call CallMsg, blockNumber *big.Int) ([]byte, error)
+}
+
+// FilterQuery contains options for contact log filtering.
+type FilterQuery struct {
+	FromBlock *big.Int         // beginning of the queried range, nil means genesis block
+	ToBlock   *big.Int         // end of the range, nil means latest block
+	Addresses []common.Address // restricts matches to events created by specific contracts
+
+	// The Topic list restricts matches to particular event topics. Each event has a list
+	// of topics. Topics matches a prefix of that list. An empty element slice matches any
+	// topic. Non-empty elements represent an alternative that matches any of the
+	// contained topics.
+	//
+	// Examples:
+	// {} or nil          matches any topic list
+	// {{A}}              matches topic A in first position
+	// {{}, {B}}          matches any topic in first position, B in second position
+	// {{A}}, {B}}        matches topic A in first position, B in second position
+	// {{A, B}}, {C, D}}  matches topic (A OR B) in first position, (C OR D) in second position
+	Topics [][]common.Hash
+}
+
+// LogFilterer provides access to contract log events using a one-off query or continuous
+// event subscription.
+type LogFilterer interface {
+	FilterLogs(ctx context.Context, q FilterQuery) ([]vm.Log, error)
+	SubscribeFilterLogs(ctx context.Context, q FilterQuery, ch chan<- vm.Log) (Subscription, error)
+}
+
+// TransactionSender wraps transaction sending. The SendTransaction method injects a
+// signed transaction into the pending transaction pool for execution. If the transaction
+// was a contract creation, the TransactionReceipt method can be used to retrieve the
+// contract address after the transaction has been mined.
+//
+// The transaction must be signed and have a valid nonce to be included. Consumers of the
+// API can use package accounts to maintain local private keys and need can retrieve the
+// next available nonce using PendingNonceAt.
+type TransactionSender interface {
+	SendTransaction(ctx context.Context, tx *types.Transaction) error
+}
+
+// GasPricer wraps the gas price oracle, which monitors the blockchain to determine the
+// optimal gas price given current fee market conditions.
+type GasPricer interface {
+	SuggestGasPrice(ctx context.Context) (*big.Int, error)
+}
+
+// A PendingStateReader provides access to the pending state, which is the result of all
+// known executable transactions which have not yet been included in the blockchain. It is
+// commonly used to display the result of ’unconfirmed’ actions (e.g. wallet value
+// transfers) initiated by the user. The PendingNonceAt operation is a good way to
+// retrieve the next available transaction nonce for a specific account.
+type PendingStateReader interface {
+	PendingBalanceAt(ctx context.Context, account common.Address) (*big.Int, error)
+	PendingStorageAt(ctx context.Context, account common.Address, key common.Hash) ([]byte, error)
+	PendingCodeAt(ctx context.Context, account common.Address) ([]byte, error)
+	PendingNonceAt(ctx context.Context, account common.Address) (uint64, error)
+	PendingTransactionCount(ctx context.Context) (uint, error)
+}
+
+// PendingContractCaller can be used to perform calls against the pending state.
+type PendingContractCaller interface {
+	PendingCallContract(ctx context.Context, call CallMsg) ([]byte, error)
+}
+
+// GasEstimator wraps EstimateGas, which tries to estimate the gas needed to execute a
+// specific transaction based on the pending state. There is no guarantee that this is the
+// true gas limit requirement as other transactions may be added or removed by miners, but
+// it should provide a basis for setting a reasonable default.
+type GasEstimator interface {
+	EstimateGas(ctx context.Context, call CallMsg) (usedGas *big.Int, err error)
+}
+
+// A PendingStateEventer provides access to real time notifications about changes to the
+// pending state.
+type PendingStateEventer interface {
+	SubscribePendingTransactions(ctx context.Context, ch chan<- *types.Transaction) (Subscription, error)
+}
diff --git a/internal/ethapi/api.go b/internal/ethapi/api.go
index 135f9f8e8..184b5831f 100644
--- a/internal/ethapi/api.go
+++ b/internal/ethapi/api.go
@@ -588,24 +588,26 @@ func FormatLogs(structLogs []vm.StructLog) []StructLogRes {
 // returned. When fullTx is true the returned block contains full transaction details, otherwise it will only contain
 // transaction hashes.
 func (s *PublicBlockChainAPI) rpcOutputBlock(b *types.Block, inclTx bool, fullTx bool) (map[string]interface{}, error) {
+	head := b.Header() // copies the header once
 	fields := map[string]interface{}{
-		"number":           rpc.NewHexNumber(b.Number()),
+		"number":           rpc.NewHexNumber(head.Number),
 		"hash":             b.Hash(),
-		"parentHash":       b.ParentHash(),
-		"nonce":            b.Header().Nonce,
-		"sha3Uncles":       b.UncleHash(),
-		"logsBloom":        b.Bloom(),
-		"stateRoot":        b.Root(),
-		"miner":            b.Coinbase(),
-		"difficulty":       rpc.NewHexNumber(b.Difficulty()),
+		"parentHash":       head.ParentHash,
+		"nonce":            head.Nonce,
+		"mixHash":          head.MixDigest,
+		"sha3Uncles":       head.UncleHash,
+		"logsBloom":        head.Bloom,
+		"stateRoot":        head.Root,
+		"miner":            head.Coinbase,
+		"difficulty":       rpc.NewHexNumber(head.Difficulty),
 		"totalDifficulty":  rpc.NewHexNumber(s.b.GetTd(b.Hash())),
-		"extraData":        fmt.Sprintf("0x%x", b.Extra()),
+		"extraData":        rpc.HexBytes(head.Extra),
 		"size":             rpc.NewHexNumber(b.Size().Int64()),
-		"gasLimit":         rpc.NewHexNumber(b.GasLimit()),
-		"gasUsed":          rpc.NewHexNumber(b.GasUsed()),
-		"timestamp":        rpc.NewHexNumber(b.Time()),
-		"transactionsRoot": b.TxHash(),
-		"receiptRoot":      b.ReceiptHash(),
+		"gasLimit":         rpc.NewHexNumber(head.GasLimit),
+		"gasUsed":          rpc.NewHexNumber(head.GasUsed),
+		"timestamp":        rpc.NewHexNumber(head.Time),
+		"transactionsRoot": head.TxHash,
+		"receiptRoot":      head.ReceiptHash,
 	}
 
 	if inclTx {
@@ -648,26 +650,32 @@ type RPCTransaction struct {
 	Gas              *rpc.HexNumber  `json:"gas"`
 	GasPrice         *rpc.HexNumber  `json:"gasPrice"`
 	Hash             common.Hash     `json:"hash"`
-	Input            string          `json:"input"`
+	Input            rpc.HexBytes    `json:"input"`
 	Nonce            *rpc.HexNumber  `json:"nonce"`
 	To               *common.Address `json:"to"`
 	TransactionIndex *rpc.HexNumber  `json:"transactionIndex"`
 	Value            *rpc.HexNumber  `json:"value"`
+	V                *rpc.HexNumber  `json:"v"`
+	R                *rpc.HexNumber  `json:"r"`
+	S                *rpc.HexNumber  `json:"s"`
 }
 
 // newRPCPendingTransaction returns a pending transaction that will serialize to the RPC representation
 func newRPCPendingTransaction(tx *types.Transaction) *RPCTransaction {
 	from, _ := tx.FromFrontier()
-
+	v, r, s := tx.SignatureValues()
 	return &RPCTransaction{
 		From:     from,
 		Gas:      rpc.NewHexNumber(tx.Gas()),
 		GasPrice: rpc.NewHexNumber(tx.GasPrice()),
 		Hash:     tx.Hash(),
-		Input:    fmt.Sprintf("0x%x", tx.Data()),
+		Input:    rpc.HexBytes(tx.Data()),
 		Nonce:    rpc.NewHexNumber(tx.Nonce()),
 		To:       tx.To(),
 		Value:    rpc.NewHexNumber(tx.Value()),
+		V:        rpc.NewHexNumber(v),
+		R:        rpc.NewHexNumber(r),
+		S:        rpc.NewHexNumber(s),
 	}
 }
 
@@ -679,7 +687,7 @@ func newRPCTransactionFromBlockIndex(b *types.Block, txIndex int) (*RPCTransacti
 		if err != nil {
 			return nil, err
 		}
-
+		v, r, s := tx.SignatureValues()
 		return &RPCTransaction{
 			BlockHash:        b.Hash(),
 			BlockNumber:      rpc.NewHexNumber(b.Number()),
@@ -687,11 +695,14 @@ func newRPCTransactionFromBlockIndex(b *types.Block, txIndex int) (*RPCTransacti
 			Gas:              rpc.NewHexNumber(tx.Gas()),
 			GasPrice:         rpc.NewHexNumber(tx.GasPrice()),
 			Hash:             tx.Hash(),
-			Input:            fmt.Sprintf("0x%x", tx.Data()),
+			Input:            rpc.HexBytes(tx.Data()),
 			Nonce:            rpc.NewHexNumber(tx.Nonce()),
 			To:               tx.To(),
 			TransactionIndex: rpc.NewHexNumber(txIndex),
 			Value:            rpc.NewHexNumber(tx.Value()),
+			V:                rpc.NewHexNumber(v),
+			R:                rpc.NewHexNumber(r),
+			S:                rpc.NewHexNumber(s),
 		}, nil
 	}
 
@@ -861,7 +872,7 @@ func (s *PublicTransactionPoolAPI) GetTransactionReceipt(txHash common.Hash) (ma
 	}
 
 	fields := map[string]interface{}{
-		"root":              common.Bytes2Hex(receipt.PostState),
+		"root":              rpc.HexBytes(receipt.PostState),
 		"blockHash":         txBlock,
 		"blockNumber":       rpc.NewHexNumber(blockIndex),
 		"transactionHash":   txHash,
@@ -872,17 +883,15 @@ func (s *PublicTransactionPoolAPI) GetTransactionReceipt(txHash common.Hash) (ma
 		"cumulativeGasUsed": rpc.NewHexNumber(receipt.CumulativeGasUsed),
 		"contractAddress":   nil,
 		"logs":              receipt.Logs,
+		"logsBloom":         receipt.Bloom,
 	}
-
 	if receipt.Logs == nil {
 		fields["logs"] = []vm.Logs{}
 	}
-
 	// If the ContractAddress is 20 0x0 bytes, assume it is not a contract creation
-	if bytes.Compare(receipt.ContractAddress.Bytes(), bytes.Repeat([]byte{0}, 20)) != 0 {
+	if receipt.ContractAddress != (common.Address{}) {
 		fields["contractAddress"] = receipt.ContractAddress
 	}
-
 	return fields, nil
 }
 
diff --git a/rpc/types.go b/rpc/types.go
index 89c5b5bc9..ebe388373 100644
--- a/rpc/types.go
+++ b/rpc/types.go
@@ -17,6 +17,8 @@
 package rpc
 
 import (
+	"bytes"
+	"encoding/hex"
 	"fmt"
 	"math"
 	"math/big"
@@ -272,3 +274,31 @@ func (bn *BlockNumber) UnmarshalJSON(data []byte) error {
 func (bn BlockNumber) Int64() int64 {
 	return (int64)(bn)
 }
+
+// HexBytes JSON-encodes as hex with 0x prefix.
+type HexBytes []byte
+
+func (b HexBytes) MarshalJSON() ([]byte, error) {
+	result := make([]byte, len(b)*2+4)
+	copy(result, `"0x`)
+	hex.Encode(result[3:], b)
+	result[len(result)-1] = '"'
+	return result, nil
+}
+
+func (b *HexBytes) UnmarshalJSON(input []byte) error {
+	if len(input) >= 2 && input[0] == '"' && input[len(input)-1] == '"' {
+		input = input[1 : len(input)-1]
+	}
+	if !bytes.HasPrefix(input, []byte("0x")) {
+		return fmt.Errorf("missing 0x prefix for hex byte array")
+	}
+	input = input[2:]
+	if len(input) == 0 {
+		*b = nil
+		return nil
+	}
+	*b = make([]byte, len(input)/2)
+	_, err := hex.Decode(*b, input)
+	return err
+}
diff --git a/rpc/types_test.go b/rpc/types_test.go
index c2c5c6db6..5482557b8 100644
--- a/rpc/types_test.go
+++ b/rpc/types_test.go
@@ -71,3 +71,25 @@ func TestHexNumberMarshalJSON(t *testing.T) {
 		t.Fatalf("Invalid json.Marshal, expected '%s', got '%s'", exp, got)
 	}
 }
+
+var hexBytesTests = []struct{ in, out []byte }{
+	{in: []byte(`"0x"`), out: []byte{}},
+	{in: []byte(`"0x00"`), out: []byte{0}},
+	{in: []byte(`"0x01ff"`), out: []byte{0x01, 0xFF}},
+}
+
+func TestHexBytes(t *testing.T) {
+	for i, test := range hexBytesTests {
+		var dec HexBytes
+		if err := json.Unmarshal(test.in, &dec); err != nil {
+			t.Fatalf("test %d: can't decode: %v", i, err)
+		}
+		enc, _ := json.Marshal(HexBytes(test.out))
+		if !bytes.Equal(dec, test.out) {
+			t.Errorf("test %d: wrong decoded value 0x%x", i, dec)
+		}
+		if !bytes.Equal(enc, test.in) {
+			t.Errorf("test %d: wrong encoded value %#q", i, enc)
+		}
+	}
+}