diff --git a/accounts/abi/bind/backends/simulated.go b/accounts/abi/bind/backends/simulated.go
index cd14afa14755..82b2ee820a20 100644
--- a/accounts/abi/bind/backends/simulated.go
+++ b/accounts/abi/bind/backends/simulated.go
@@ -79,7 +79,7 @@ type SimulatedBackend struct {
 func NewSimulatedBackendWithDatabase(database ethdb.Database, alloc core.GenesisAlloc, gasLimit uint64) *SimulatedBackend {
 	genesis := core.Genesis{Config: params.AllEthashProtocolChanges, GasLimit: gasLimit, Alloc: alloc}
 	genesis.MustCommit(database)
-	blockchain, _ := core.NewBlockChain(database, nil, genesis.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := core.NewBlockChain(database, nil, &genesis, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 
 	backend := &SimulatedBackend{
 		database:   database,
diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go
index efea9349250d..7c33941126f5 100644
--- a/cmd/utils/flags.go
+++ b/cmd/utils/flags.go
@@ -33,7 +33,6 @@ import (
 	"github.com/ethereum/go-ethereum/accounts/keystore"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/fdlimit"
-	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/rawdb"
@@ -2142,20 +2141,20 @@ func MakeGenesis(ctx *cli.Context) *core.Genesis {
 }
 
 // MakeChain creates a chain manager from set command line flags.
-func MakeChain(ctx *cli.Context, stack *node.Node) (chain *core.BlockChain, chainDb ethdb.Database) {
-	var err error
-	chainDb = MakeChainDatabase(ctx, stack, false) // TODO(rjl493456442) support read-only database
-	config, _, err := core.SetupGenesisBlock(chainDb, MakeGenesis(ctx))
+func MakeChain(ctx *cli.Context, stack *node.Node) (*core.BlockChain, ethdb.Database) {
+	var (
+		gspec   = MakeGenesis(ctx)
+		chainDb = MakeChainDatabase(ctx, stack, false) // TODO(rjl493456442) support read-only database
+	)
+	cliqueConfig, err := core.LoadCliqueConfig(chainDb, gspec)
 	if err != nil {
 		Fatalf("%v", err)
 	}
-
-	var engine consensus.Engine
-	ethashConf := ethconfig.Defaults.Ethash
+	ethashConfig := ethconfig.Defaults.Ethash
 	if ctx.Bool(FakePoWFlag.Name) {
-		ethashConf.PowMode = ethash.ModeFake
+		ethashConfig.PowMode = ethash.ModeFake
 	}
-	engine = ethconfig.CreateConsensusEngine(stack, config, &ethashConf, nil, false, chainDb)
+	engine := ethconfig.CreateConsensusEngine(stack, &ethashConfig, cliqueConfig, nil, false, chainDb)
 	if gcmode := ctx.String(GCModeFlag.Name); gcmode != "full" && gcmode != "archive" {
 		Fatalf("--%s must be either 'full' or 'archive'", GCModeFlag.Name)
 	}
@@ -2185,7 +2184,7 @@ func MakeChain(ctx *cli.Context, stack *node.Node) (chain *core.BlockChain, chai
 
 	// TODO(rjl493456442) disable snapshot generation/wiping if the chain is read only.
 	// Disable transaction indexing/unindexing by default.
-	chain, err = core.NewBlockChain(chainDb, cache, config, engine, vmcfg, nil, nil)
+	chain, err := core.NewBlockChain(chainDb, cache, gspec, nil, engine, vmcfg, nil, nil)
 	if err != nil {
 		Fatalf("Can't create BlockChain: %v", err)
 	}
diff --git a/consensus/clique/clique_test.go b/consensus/clique/clique_test.go
index 1bd32acd3746..74d884a21b9f 100644
--- a/consensus/clique/clique_test.go
+++ b/consensus/clique/clique_test.go
@@ -45,6 +45,7 @@ func TestReimportMirroredState(t *testing.T) {
 		signer = new(types.HomesteadSigner)
 	)
 	genspec := &core.Genesis{
+		Config:    params.AllCliqueProtocolChanges,
 		ExtraData: make([]byte, extraVanity+common.AddressLength+extraSeal),
 		Alloc: map[common.Address]core.GenesisAccount{
 			addr: {Balance: big.NewInt(10000000000000000)},
@@ -55,7 +56,7 @@ func TestReimportMirroredState(t *testing.T) {
 	genesis := genspec.MustCommit(db)
 
 	// Generate a batch of blocks, each properly signed
-	chain, _ := core.NewBlockChain(db, nil, params.AllCliqueProtocolChanges, engine, vm.Config{}, nil, nil)
+	chain, _ := core.NewBlockChain(db, nil, genspec, nil, engine, vm.Config{}, nil, nil)
 	defer chain.Stop()
 
 	blocks, _ := core.GenerateChain(params.AllCliqueProtocolChanges, genesis, engine, db, 3, func(i int, block *core.BlockGen) {
@@ -89,7 +90,7 @@ func TestReimportMirroredState(t *testing.T) {
 	db = rawdb.NewMemoryDatabase()
 	genspec.MustCommit(db)
 
-	chain, _ = core.NewBlockChain(db, nil, params.AllCliqueProtocolChanges, engine, vm.Config{}, nil, nil)
+	chain, _ = core.NewBlockChain(db, nil, genspec, nil, engine, vm.Config{}, nil, nil)
 	defer chain.Stop()
 
 	if _, err := chain.InsertChain(blocks[:2]); err != nil {
@@ -102,7 +103,7 @@ func TestReimportMirroredState(t *testing.T) {
 	// Simulate a crash by creating a new chain on top of the database, without
 	// flushing the dirty states out. Insert the last block, triggering a sidechain
 	// reimport.
-	chain, _ = core.NewBlockChain(db, nil, params.AllCliqueProtocolChanges, engine, vm.Config{}, nil, nil)
+	chain, _ = core.NewBlockChain(db, nil, genspec, nil, engine, vm.Config{}, nil, nil)
 	defer chain.Stop()
 
 	if _, err := chain.InsertChain(blocks[2:]); err != nil {
diff --git a/consensus/clique/snapshot_test.go b/consensus/clique/snapshot_test.go
index b87ad8c23a7c..62d4e4634142 100644
--- a/consensus/clique/snapshot_test.go
+++ b/consensus/clique/snapshot_test.go
@@ -411,6 +411,7 @@ func TestClique(t *testing.T) {
 			Period: 1,
 			Epoch:  tt.epoch,
 		}
+		genesis.Config = &config
 		engine := New(config.Clique, db)
 		engine.fakeDiff = true
 
@@ -450,7 +451,7 @@ func TestClique(t *testing.T) {
 			batches[len(batches)-1] = append(batches[len(batches)-1], block)
 		}
 		// Pass all the headers through clique and ensure tallying succeeds
-		chain, err := core.NewBlockChain(db, nil, &config, engine, vm.Config{}, nil, nil)
+		chain, err := core.NewBlockChain(db, nil, genesis, nil, engine, vm.Config{}, nil, nil)
 		if err != nil {
 			t.Errorf("test %d: failed to create test chain: %v", i, err)
 			continue
diff --git a/core/bench_test.go b/core/bench_test.go
index 3006e5513171..e448310e4d58 100644
--- a/core/bench_test.go
+++ b/core/bench_test.go
@@ -196,7 +196,7 @@ func benchInsertChain(b *testing.B, disk bool, gen func(int, *BlockGen)) {
 
 	// Time the insertion of the new chain.
 	// State and blocks are stored in the same DB.
-	chainman, _ := NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chainman, _ := NewBlockChain(db, nil, &gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer chainman.Stop()
 	b.ReportAllocs()
 	b.ResetTimer()
@@ -262,6 +262,11 @@ func makeChainForBench(db ethdb.Database, full bool, count uint64) {
 		rawdb.WriteCanonicalHash(db, hash, n)
 		rawdb.WriteTd(db, hash, n, big.NewInt(int64(n+1)))
 
+		if n == 0 {
+			rawdb.WriteChainConfig(db, hash, params.AllEthashProtocolChanges)
+		}
+		rawdb.WriteHeadHeaderHash(db, hash)
+
 		if full || n == 0 {
 			block := types.NewBlockWithHeader(header)
 			rawdb.WriteBody(db, hash, n, block.Body())
@@ -303,7 +308,7 @@ func benchReadChain(b *testing.B, full bool, count uint64) {
 		if err != nil {
 			b.Fatalf("error opening database at %v: %v", dir, err)
 		}
-		chain, err := NewBlockChain(db, &cacheConfig, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, nil)
+		chain, err := NewBlockChain(db, &cacheConfig, nil, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 		if err != nil {
 			b.Fatalf("error creating chain: %v", err)
 		}
diff --git a/core/block_validator_test.go b/core/block_validator_test.go
index 8dee8d576070..815bc86552a7 100644
--- a/core/block_validator_test.go
+++ b/core/block_validator_test.go
@@ -49,7 +49,7 @@ func TestHeaderVerification(t *testing.T) {
 		headers[i] = block.Header()
 	}
 	// Run the header checker for blocks one-by-one, checking for both valid and invalid nonces
-	chain, _ := NewBlockChain(testdb, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chain, _ := NewBlockChain(testdb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer chain.Stop()
 
 	for i := 0; i < len(blocks); i++ {
@@ -89,12 +89,12 @@ func TestHeaderVerificationForMergingEthash(t *testing.T) { testHeaderVerificati
 // Tests the verification for eth1/2 merging, including pre-merge and post-merge
 func testHeaderVerificationForMerging(t *testing.T, isClique bool) {
 	var (
-		testdb      = rawdb.NewMemoryDatabase()
-		preBlocks   []*types.Block
-		postBlocks  []*types.Block
-		runEngine   consensus.Engine
-		chainConfig *params.ChainConfig
-		merger      = consensus.NewMerger(rawdb.NewMemoryDatabase())
+		testdb     = rawdb.NewMemoryDatabase()
+		preBlocks  []*types.Block
+		postBlocks []*types.Block
+		runEngine  consensus.Engine
+		genspec    *Genesis
+		merger     = consensus.NewMerger(rawdb.NewMemoryDatabase())
 	)
 	if isClique {
 		var (
@@ -102,7 +102,8 @@ func testHeaderVerificationForMerging(t *testing.T, isClique bool) {
 			addr   = crypto.PubkeyToAddress(key.PublicKey)
 			engine = clique.New(params.AllCliqueProtocolChanges.Clique, testdb)
 		)
-		genspec := &Genesis{
+		genspec = &Genesis{
+			Config:    params.AllCliqueProtocolChanges,
 			ExtraData: make([]byte, 32+common.AddressLength+crypto.SignatureLength),
 			Alloc: map[common.Address]GenesisAccount{
 				addr: {Balance: big.NewInt(1)},
@@ -133,11 +134,11 @@ func testHeaderVerificationForMerging(t *testing.T, isClique bool) {
 		config := *params.AllCliqueProtocolChanges
 		config.TerminalTotalDifficulty = big.NewInt(int64(td))
 		postBlocks, _ = GenerateChain(&config, preBlocks[len(preBlocks)-1], genEngine, testdb, 8, nil)
-		chainConfig = &config
 		runEngine = beacon.New(engine)
+		genspec.Config = &config
 	} else {
-		gspec := &Genesis{Config: params.TestChainConfig}
-		genesis := gspec.MustCommit(testdb)
+		genspec = &Genesis{Config: params.TestChainConfig}
+		genesis := genspec.MustCommit(testdb)
 		genEngine := beacon.New(ethash.NewFaker())
 
 		preBlocks, _ = GenerateChain(params.TestChainConfig, genesis, genEngine, testdb, 8, nil)
@@ -150,8 +151,8 @@ func testHeaderVerificationForMerging(t *testing.T, isClique bool) {
 		config.TerminalTotalDifficulty = big.NewInt(int64(td))
 		postBlocks, _ = GenerateChain(params.TestChainConfig, preBlocks[len(preBlocks)-1], genEngine, testdb, 8, nil)
 
-		chainConfig = &config
 		runEngine = beacon.New(ethash.NewFaker())
+		genspec.Config = &config
 	}
 
 	preHeaders := make([]*types.Header, len(preBlocks))
@@ -169,7 +170,7 @@ func testHeaderVerificationForMerging(t *testing.T, isClique bool) {
 		t.Logf("Log header after the merging %d: %v", block.NumberU64(), string(blob))
 	}
 	// Run the header checker for blocks one-by-one, checking for both valid and invalid nonces
-	chain, _ := NewBlockChain(testdb, nil, chainConfig, runEngine, vm.Config{}, nil, nil)
+	chain, _ := NewBlockChain(testdb, nil, genspec, nil, runEngine, vm.Config{}, nil, nil)
 	defer chain.Stop()
 
 	// Verify the blocks before the merging
@@ -280,11 +281,11 @@ func testHeaderConcurrentVerification(t *testing.T, threads int) {
 		var results <-chan error
 
 		if valid {
-			chain, _ := NewBlockChain(testdb, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, nil)
+			chain, _ := NewBlockChain(testdb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 			_, results = chain.engine.VerifyHeaders(chain, headers, seals)
 			chain.Stop()
 		} else {
-			chain, _ := NewBlockChain(testdb, nil, params.TestChainConfig, ethash.NewFakeFailer(uint64(len(headers)-1)), vm.Config{}, nil, nil)
+			chain, _ := NewBlockChain(testdb, nil, gspec, nil, ethash.NewFakeFailer(uint64(len(headers)-1)), vm.Config{}, nil, nil)
 			_, results = chain.engine.VerifyHeaders(chain, headers, seals)
 			chain.Stop()
 		}
@@ -347,7 +348,7 @@ func testHeaderConcurrentAbortion(t *testing.T, threads int) {
 	defer runtime.GOMAXPROCS(old)
 
 	// Start the verifications and immediately abort
-	chain, _ := NewBlockChain(testdb, nil, params.TestChainConfig, ethash.NewFakeDelayer(time.Millisecond), vm.Config{}, nil, nil)
+	chain, _ := NewBlockChain(testdb, nil, gspec, nil, ethash.NewFakeDelayer(time.Millisecond), vm.Config{}, nil, nil)
 	defer chain.Stop()
 
 	abort, results := chain.engine.VerifyHeaders(chain, headers, seals)
diff --git a/core/blockchain.go b/core/blockchain.go
index f35de404619b..e6daac5eda0f 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -23,6 +23,7 @@ import (
 	"io"
 	"math/big"
 	"sort"
+	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -218,7 +219,7 @@ type BlockChain struct {
 // NewBlockChain returns a fully initialised block chain using information
 // available in the database. It initialises the default Ethereum Validator
 // and Processor.
-func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *params.ChainConfig, engine consensus.Engine, vmConfig vm.Config, shouldPreserve func(header *types.Header) bool, txLookupLimit *uint64) (*BlockChain, error) {
+func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, genesis *Genesis, overrides *ChainOverrides, engine consensus.Engine, vmConfig vm.Config, shouldPreserve func(header *types.Header) bool, txLookupLimit *uint64) (*BlockChain, error) {
 	if cacheConfig == nil {
 		cacheConfig = defaultCacheConfig
 	}
@@ -229,6 +230,21 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *par
 	txLookupCache, _ := lru.New(txLookupCacheLimit)
 	futureBlocks, _ := lru.New(maxFutureBlocks)
 
+	// Setup the genesis block, commit the provided genesis specification
+	// to database if the genesis block is not present yet, or load the
+	// stored one from database.
+	chainConfig, genesisHash, genesisErr := SetupGenesisBlockWithOverride(db, genesis, overrides)
+	if _, ok := genesisErr.(*params.ConfigCompatError); genesisErr != nil && !ok {
+		return nil, genesisErr
+	}
+	log.Info("")
+	log.Info(strings.Repeat("-", 153))
+	for _, line := range strings.Split(chainConfig.String(), "\n") {
+		log.Info(line)
+	}
+	log.Info(strings.Repeat("-", 153))
+	log.Info("")
+
 	bc := &BlockChain{
 		chainConfig: chainConfig,
 		cacheConfig: cacheConfig,
@@ -409,6 +425,12 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *par
 			triedb.SaveCachePeriodically(bc.cacheConfig.TrieCleanJournal, bc.cacheConfig.TrieCleanRejournal, bc.quit)
 		}()
 	}
+	// Rewind the chain in case of an incompatible config upgrade.
+	if compat, ok := genesisErr.(*params.ConfigCompatError); ok {
+		log.Warn("Rewinding chain to upgrade configuration", "err", compat)
+		bc.SetHead(compat.RewindTo)
+		rawdb.WriteChainConfig(db, genesisHash, chainConfig)
+	}
 	return bc, nil
 }
 
diff --git a/core/blockchain_repair_test.go b/core/blockchain_repair_test.go
index 24309405d2b3..463e357c3834 100644
--- a/core/blockchain_repair_test.go
+++ b/core/blockchain_repair_test.go
@@ -1764,7 +1764,11 @@ func testRepair(t *testing.T, tt *rewindTest, snapshots bool) {
 
 	// Initialize a fresh chain
 	var (
-		genesis = (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+		gspec = &Genesis{
+			BaseFee: big.NewInt(params.InitialBaseFee),
+			Config:  params.AllEthashProtocolChanges,
+		}
+		genesis = gspec.MustCommit(db)
 		engine  = ethash.NewFullFaker()
 		config  = &CacheConfig{
 			TrieCleanLimit: 256,
@@ -1778,7 +1782,7 @@ func testRepair(t *testing.T, tt *rewindTest, snapshots bool) {
 		config.SnapshotLimit = 256
 		config.SnapshotWait = true
 	}
-	chain, err := NewBlockChain(db, config, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(db, config, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to create chain: %v", err)
 	}
@@ -1831,7 +1835,7 @@ func testRepair(t *testing.T, tt *rewindTest, snapshots bool) {
 	}
 	defer db.Close()
 
-	newChain, err := NewBlockChain(db, nil, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
+	newChain, err := NewBlockChain(db, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -1888,7 +1892,11 @@ func TestIssue23496(t *testing.T) {
 
 	// Initialize a fresh chain
 	var (
-		genesis = (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+		gspec = &Genesis{
+			Config:  params.TestChainConfig,
+			BaseFee: big.NewInt(params.InitialBaseFee),
+		}
+		genesis = gspec.MustCommit(db)
 		engine  = ethash.NewFullFaker()
 		config  = &CacheConfig{
 			TrieCleanLimit: 256,
@@ -1898,7 +1906,7 @@ func TestIssue23496(t *testing.T) {
 			SnapshotWait:   true,
 		}
 	)
-	chain, err := NewBlockChain(db, config, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(db, config, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to create chain: %v", err)
 	}
@@ -1942,7 +1950,7 @@ func TestIssue23496(t *testing.T) {
 	}
 	defer db.Close()
 
-	chain, err = NewBlockChain(db, nil, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
+	chain, err = NewBlockChain(db, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
diff --git a/core/blockchain_sethead_test.go b/core/blockchain_sethead_test.go
index d8103b5b5c50..c5df7949ef6c 100644
--- a/core/blockchain_sethead_test.go
+++ b/core/blockchain_sethead_test.go
@@ -1964,7 +1964,11 @@ func testSetHead(t *testing.T, tt *rewindTest, snapshots bool) {
 
 	// Initialize a fresh chain
 	var (
-		genesis = (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+		gspec = &Genesis{
+			BaseFee: big.NewInt(params.InitialBaseFee),
+			Config:  params.AllEthashProtocolChanges,
+		}
+		genesis = gspec.MustCommit(db)
 		engine  = ethash.NewFullFaker()
 		config  = &CacheConfig{
 			TrieCleanLimit: 256,
@@ -1977,7 +1981,7 @@ func testSetHead(t *testing.T, tt *rewindTest, snapshots bool) {
 		config.SnapshotLimit = 256
 		config.SnapshotWait = true
 	}
-	chain, err := NewBlockChain(db, config, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(db, config, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to create chain: %v", err)
 	}
diff --git a/core/blockchain_snapshot_test.go b/core/blockchain_snapshot_test.go
index 189eee59a009..01a88d7a3c7d 100644
--- a/core/blockchain_snapshot_test.go
+++ b/core/blockchain_snapshot_test.go
@@ -54,6 +54,7 @@ type snapshotTestBasic struct {
 	db      ethdb.Database
 	gendb   ethdb.Database
 	engine  consensus.Engine
+	gspec   *Genesis
 }
 
 func (basic *snapshotTestBasic) prepare(t *testing.T) (*BlockChain, []*types.Block) {
@@ -66,7 +67,11 @@ func (basic *snapshotTestBasic) prepare(t *testing.T) (*BlockChain, []*types.Blo
 	}
 	// Initialize a fresh chain
 	var (
-		genesis = (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+		gspec = &Genesis{
+			BaseFee: big.NewInt(params.InitialBaseFee),
+			Config:  params.AllEthashProtocolChanges,
+		}
+		genesis = gspec.MustCommit(db)
 		engine  = ethash.NewFullFaker()
 		gendb   = rawdb.NewMemoryDatabase()
 
@@ -75,7 +80,7 @@ func (basic *snapshotTestBasic) prepare(t *testing.T) (*BlockChain, []*types.Blo
 		// will happen during the block insertion.
 		cacheConfig = defaultCacheConfig
 	)
-	chain, err := NewBlockChain(db, cacheConfig, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(db, cacheConfig, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to create chain: %v", err)
 	}
@@ -118,6 +123,7 @@ func (basic *snapshotTestBasic) prepare(t *testing.T) (*BlockChain, []*types.Blo
 	basic.db = db
 	basic.gendb = gendb
 	basic.engine = engine
+	basic.gspec = gspec
 	return chain, blocks
 }
 
@@ -219,7 +225,7 @@ func (snaptest *snapshotTest) test(t *testing.T) {
 
 	// Restart the chain normally
 	chain.Stop()
-	newchain, err := NewBlockChain(snaptest.db, nil, params.AllEthashProtocolChanges, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(snaptest.db, nil, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -255,13 +261,13 @@ func (snaptest *crashSnapshotTest) test(t *testing.T) {
 	// the crash, we do restart twice here: one after the crash and one
 	// after the normal stop. It's used to ensure the broken snapshot
 	// can be detected all the time.
-	newchain, err := NewBlockChain(newdb, nil, params.AllEthashProtocolChanges, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(newdb, nil, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
 	newchain.Stop()
 
-	newchain, err = NewBlockChain(newdb, nil, params.AllEthashProtocolChanges, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err = NewBlockChain(newdb, nil, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -297,7 +303,7 @@ func (snaptest *gappedSnapshotTest) test(t *testing.T) {
 		TrieTimeLimit:  5 * time.Minute,
 		SnapshotLimit:  0,
 	}
-	newchain, err := NewBlockChain(snaptest.db, cacheConfig, params.AllEthashProtocolChanges, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(snaptest.db, cacheConfig, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -305,7 +311,7 @@ func (snaptest *gappedSnapshotTest) test(t *testing.T) {
 	newchain.Stop()
 
 	// Restart the chain with enabling the snapshot
-	newchain, err = NewBlockChain(snaptest.db, nil, params.AllEthashProtocolChanges, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err = NewBlockChain(snaptest.db, nil, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -333,7 +339,7 @@ func (snaptest *setHeadSnapshotTest) test(t *testing.T) {
 	chain.SetHead(snaptest.setHead)
 	chain.Stop()
 
-	newchain, err := NewBlockChain(snaptest.db, nil, params.AllEthashProtocolChanges, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(snaptest.db, nil, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -368,7 +374,7 @@ func (snaptest *wipeCrashSnapshotTest) test(t *testing.T) {
 		TrieTimeLimit:  5 * time.Minute,
 		SnapshotLimit:  0,
 	}
-	newchain, err := NewBlockChain(snaptest.db, config, params.AllEthashProtocolChanges, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err := NewBlockChain(snaptest.db, config, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
@@ -384,13 +390,13 @@ func (snaptest *wipeCrashSnapshotTest) test(t *testing.T) {
 		SnapshotLimit:  256,
 		SnapshotWait:   false, // Don't wait rebuild
 	}
-	_, err = NewBlockChain(snaptest.db, config, params.AllEthashProtocolChanges, snaptest.engine, vm.Config{}, nil, nil)
+	_, err = NewBlockChain(snaptest.db, config, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
 	// Simulate the blockchain crash.
 
-	newchain, err = NewBlockChain(snaptest.db, nil, params.AllEthashProtocolChanges, snaptest.engine, vm.Config{}, nil, nil)
+	newchain, err = NewBlockChain(snaptest.db, nil, snaptest.gspec, nil, snaptest.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to recreate chain: %v", err)
 	}
diff --git a/core/blockchain_test.go b/core/blockchain_test.go
index 44256f6187da..713ac2809a2a 100644
--- a/core/blockchain_test.go
+++ b/core/blockchain_test.go
@@ -53,12 +53,16 @@ var (
 // header only chain.
 func newCanonical(engine consensus.Engine, n int, full bool) (ethdb.Database, *BlockChain, error) {
 	var (
-		db      = rawdb.NewMemoryDatabase()
-		genesis = (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+		db    = rawdb.NewMemoryDatabase()
+		gspec = &Genesis{
+			BaseFee: big.NewInt(params.InitialBaseFee),
+			Config:  params.AllEthashProtocolChanges,
+		}
+		genesis = gspec.MustCommit(db)
 	)
 
 	// Initialize a fresh chain with only a genesis block
-	blockchain, _ := NewBlockChain(db, nil, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	// Create and inject the requested chain
 	if n == 0 {
 		return db, blockchain, nil
@@ -654,7 +658,11 @@ func testReorgBadHashes(t *testing.T, full bool) {
 	blockchain.Stop()
 
 	// Create a new BlockChain and check that it rolled back the state.
-	ncm, err := NewBlockChain(blockchain.db, nil, blockchain.chainConfig, ethash.NewFaker(), vm.Config{}, nil, nil)
+	gspec := &Genesis{
+		BaseFee: big.NewInt(params.InitialBaseFee),
+		Config:  params.AllEthashProtocolChanges,
+	}
+	ncm, err := NewBlockChain(blockchain.db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create new chain manager: %v", err)
 	}
@@ -767,7 +775,7 @@ func TestFastVsFullChains(t *testing.T) {
 	// Import the chain as an archive node for the comparison baseline
 	archiveDb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(archiveDb)
-	archive, _ := NewBlockChain(archiveDb, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	archive, _ := NewBlockChain(archiveDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer archive.Stop()
 
 	if n, err := archive.InsertChain(blocks); err != nil {
@@ -776,7 +784,7 @@ func TestFastVsFullChains(t *testing.T) {
 	// Fast import the chain as a non-archive node to test
 	fastDb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(fastDb)
-	fast, _ := NewBlockChain(fastDb, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	fast, _ := NewBlockChain(fastDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer fast.Stop()
 
 	headers := make([]*types.Header, len(blocks))
@@ -797,7 +805,7 @@ func TestFastVsFullChains(t *testing.T) {
 	}
 	defer ancientDb.Close()
 	gspec.MustCommit(ancientDb)
-	ancient, _ := NewBlockChain(ancientDb, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancient, _ := NewBlockChain(ancientDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer ancient.Stop()
 
 	if n, err := ancient.InsertHeaderChain(headers, 1); err != nil {
@@ -915,7 +923,7 @@ func TestLightVsFastVsFullChainHeads(t *testing.T) {
 	archiveCaching := *defaultCacheConfig
 	archiveCaching.TrieDirtyDisabled = true
 
-	archive, _ := NewBlockChain(archiveDb, &archiveCaching, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	archive, _ := NewBlockChain(archiveDb, &archiveCaching, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	if n, err := archive.InsertChain(blocks); err != nil {
 		t.Fatalf("failed to process block %d: %v", n, err)
 	}
@@ -928,7 +936,7 @@ func TestLightVsFastVsFullChainHeads(t *testing.T) {
 	// Import the chain as a non-archive node and ensure all pointers are updated
 	fastDb := makeDb()
 	defer fastDb.Close()
-	fast, _ := NewBlockChain(fastDb, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	fast, _ := NewBlockChain(fastDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer fast.Stop()
 
 	headers := make([]*types.Header, len(blocks))
@@ -948,7 +956,7 @@ func TestLightVsFastVsFullChainHeads(t *testing.T) {
 	// Import the chain as a ancient-first node and ensure all pointers are updated
 	ancientDb := makeDb()
 	defer ancientDb.Close()
-	ancient, _ := NewBlockChain(ancientDb, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancient, _ := NewBlockChain(ancientDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer ancient.Stop()
 
 	if n, err := ancient.InsertHeaderChain(headers, 1); err != nil {
@@ -967,7 +975,7 @@ func TestLightVsFastVsFullChainHeads(t *testing.T) {
 	// Import the chain as a light node and ensure all pointers are updated
 	lightDb := makeDb()
 	defer lightDb.Close()
-	light, _ := NewBlockChain(lightDb, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	light, _ := NewBlockChain(lightDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	if n, err := light.InsertHeaderChain(headers, 1); err != nil {
 		t.Fatalf("failed to insert header %d: %v", n, err)
 	}
@@ -1036,7 +1044,7 @@ func TestChainTxReorgs(t *testing.T) {
 		}
 	})
 	// Import the chain. This runs all block validation rules.
-	blockchain, _ := NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	if i, err := blockchain.InsertChain(chain); err != nil {
 		t.Fatalf("failed to insert original chain[%d]: %v", i, err)
 	}
@@ -1106,7 +1114,7 @@ func TestLogReorgs(t *testing.T) {
 		signer  = types.LatestSigner(gspec.Config)
 	)
 
-	blockchain, _ := NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer blockchain.Stop()
 
 	rmLogsCh := make(chan RemovedLogsEvent)
@@ -1159,7 +1167,7 @@ func TestLogRebirth(t *testing.T) {
 		genesis       = gspec.MustCommit(db)
 		signer        = types.LatestSigner(gspec.Config)
 		engine        = ethash.NewFaker()
-		blockchain, _ = NewBlockChain(db, nil, gspec.Config, engine, vm.Config{}, nil, nil)
+		blockchain, _ = NewBlockChain(db, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	)
 
 	defer blockchain.Stop()
@@ -1222,7 +1230,7 @@ func TestSideLogRebirth(t *testing.T) {
 		gspec         = &Genesis{Config: params.TestChainConfig, Alloc: GenesisAlloc{addr1: {Balance: big.NewInt(10000000000000000)}}}
 		genesis       = gspec.MustCommit(db)
 		signer        = types.LatestSigner(gspec.Config)
-		blockchain, _ = NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+		blockchain, _ = NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	)
 
 	defer blockchain.Stop()
@@ -1296,7 +1304,7 @@ func TestReorgSideEvent(t *testing.T) {
 		signer  = types.LatestSigner(gspec.Config)
 	)
 
-	blockchain, _ := NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer blockchain.Stop()
 
 	chain, _ := GenerateChain(gspec.Config, genesis, ethash.NewFaker(), db, 3, func(i int, gen *BlockGen) {})
@@ -1427,7 +1435,7 @@ func TestEIP155Transition(t *testing.T) {
 		genesis = gspec.MustCommit(db)
 	)
 
-	blockchain, _ := NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer blockchain.Stop()
 
 	blocks, _ := GenerateChain(gspec.Config, genesis, ethash.NewFaker(), db, 4, func(i int, block *BlockGen) {
@@ -1535,7 +1543,7 @@ func TestEIP161AccountRemoval(t *testing.T) {
 		}
 		genesis = gspec.MustCommit(db)
 	)
-	blockchain, _ := NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer blockchain.Stop()
 
 	blocks, _ := GenerateChain(gspec.Config, genesis, ethash.NewFaker(), db, 3, func(i int, block *BlockGen) {
@@ -1592,7 +1600,11 @@ func TestBlockchainHeaderchainReorgConsistency(t *testing.T) {
 	engine := ethash.NewFaker()
 
 	db := rawdb.NewMemoryDatabase()
-	genesis := (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+	gspec := &Genesis{
+		Config:  params.TestChainConfig,
+		BaseFee: big.NewInt(params.InitialBaseFee),
+	}
+	genesis := gspec.MustCommit(db)
 	blocks, _ := GenerateChain(params.TestChainConfig, genesis, engine, db, 64, func(i int, b *BlockGen) { b.SetCoinbase(common.Address{1}) })
 
 	// Generate a bunch of fork blocks, each side forking from the canonical chain
@@ -1610,7 +1622,7 @@ func TestBlockchainHeaderchainReorgConsistency(t *testing.T) {
 	diskdb := rawdb.NewMemoryDatabase()
 	(&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(diskdb)
 
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -1637,7 +1649,11 @@ func TestTrieForkGC(t *testing.T) {
 	engine := ethash.NewFaker()
 
 	db := rawdb.NewMemoryDatabase()
-	genesis := (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+	gspec := &Genesis{
+		BaseFee: big.NewInt(params.InitialBaseFee),
+		Config:  params.TestChainConfig,
+	}
+	genesis := gspec.MustCommit(db)
 	blocks, _ := GenerateChain(params.TestChainConfig, genesis, engine, db, 2*TriesInMemory, func(i int, b *BlockGen) { b.SetCoinbase(common.Address{1}) })
 
 	// Generate a bunch of fork blocks, each side forking from the canonical chain
@@ -1652,9 +1668,9 @@ func TestTrieForkGC(t *testing.T) {
 	}
 	// Import the canonical and fork chain side by side, forcing the trie cache to cache both
 	diskdb := rawdb.NewMemoryDatabase()
-	(&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(diskdb)
+	gspec.MustCommit(diskdb)
 
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -1683,7 +1699,11 @@ func TestLargeReorgTrieGC(t *testing.T) {
 	engine := ethash.NewFaker()
 
 	db := rawdb.NewMemoryDatabase()
-	genesis := (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+	gspec := &Genesis{
+		BaseFee: big.NewInt(params.InitialBaseFee),
+		Config:  params.TestChainConfig,
+	}
+	genesis := gspec.MustCommit(db)
 
 	shared, _ := GenerateChain(params.TestChainConfig, genesis, engine, db, 64, func(i int, b *BlockGen) { b.SetCoinbase(common.Address{1}) })
 	original, _ := GenerateChain(params.TestChainConfig, shared[len(shared)-1], engine, db, 2*TriesInMemory, func(i int, b *BlockGen) { b.SetCoinbase(common.Address{2}) })
@@ -1691,9 +1711,9 @@ func TestLargeReorgTrieGC(t *testing.T) {
 
 	// Import the shared chain and the original canonical one
 	diskdb := rawdb.NewMemoryDatabase()
-	(&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(diskdb)
+	gspec.MustCommit(diskdb)
 
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -1751,7 +1771,7 @@ func TestBlockchainRecovery(t *testing.T) {
 	}
 	defer ancientDb.Close()
 	gspec.MustCommit(ancientDb)
-	ancient, _ := NewBlockChain(ancientDb, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancient, _ := NewBlockChain(ancientDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 
 	headers := make([]*types.Header, len(blocks))
 	for i, block := range blocks {
@@ -1771,7 +1791,7 @@ func TestBlockchainRecovery(t *testing.T) {
 	rawdb.WriteHeadFastBlockHash(ancientDb, midBlock.Hash())
 
 	// Reopen broken blockchain again
-	ancient, _ = NewBlockChain(ancientDb, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancient, _ = NewBlockChain(ancientDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer ancient.Stop()
 	if num := ancient.CurrentBlock().NumberU64(); num != 0 {
 		t.Errorf("head block mismatch: have #%v, want #%v", num, 0)
@@ -1812,15 +1832,15 @@ func TestInsertReceiptChainRollback(t *testing.T) {
 	}
 
 	// Set up a BlockChain that uses the ancient store.
-	frdir := t.TempDir()
-	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "", false)
+	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), t.TempDir(), "", false)
 	if err != nil {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}
 	defer ancientDb.Close()
+
 	gspec := Genesis{Config: params.AllEthashProtocolChanges}
 	gspec.MustCommit(ancientDb)
-	ancientChain, _ := NewBlockChain(ancientDb, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	ancientChain, _ := NewBlockChain(ancientDb, nil, &gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer ancientChain.Stop()
 
 	// Import the canonical header chain.
@@ -1868,7 +1888,11 @@ func TestLowDiffLongChain(t *testing.T) {
 	// Generate a canonical chain to act as the main dataset
 	engine := ethash.NewFaker()
 	db := rawdb.NewMemoryDatabase()
-	genesis := (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+	gspec := &Genesis{
+		BaseFee: big.NewInt(params.InitialBaseFee),
+		Config:  params.TestChainConfig,
+	}
+	genesis := gspec.MustCommit(db)
 
 	// We must use a pretty long chain to ensure that the fork doesn't overtake us
 	// until after at least 128 blocks post tip
@@ -1879,9 +1903,9 @@ func TestLowDiffLongChain(t *testing.T) {
 
 	// Import the canonical chain
 	diskdb := rawdb.NewMemoryDatabase()
-	(&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(diskdb)
+	gspec.MustCommit(diskdb)
 
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -1947,7 +1971,7 @@ func testSideImport(t *testing.T, numCanonBlocksInSidechain, blocksBetweenCommon
 	// Generate and import the canonical chain
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
-	chain, err := NewBlockChain(diskdb, nil, &chainConfig, runEngine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, runEngine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2063,7 +2087,11 @@ func testInsertKnownChainData(t *testing.T, typ string) {
 	engine := ethash.NewFaker()
 
 	db := rawdb.NewMemoryDatabase()
-	genesis := (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+	gspec := &Genesis{
+		Config:  params.TestChainConfig,
+		BaseFee: big.NewInt(params.InitialBaseFee),
+	}
+	genesis := gspec.MustCommit(db)
 
 	blocks, receipts := GenerateChain(params.TestChainConfig, genesis, engine, db, 32, func(i int, b *BlockGen) { b.SetCoinbase(common.Address{1}) })
 	// A longer chain but total difficulty is lower.
@@ -2074,15 +2102,14 @@ func testInsertKnownChainData(t *testing.T, typ string) {
 		b.OffsetTime(-9) // A higher difficulty
 	})
 	// Import the shared chain and the original canonical one
-	dir := t.TempDir()
-	chaindb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), dir, "", false)
+	chaindb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), t.TempDir(), "", false)
 	if err != nil {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}
-	(&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(chaindb)
+	gspec.MustCommit(chaindb)
 	defer chaindb.Close()
 
-	chain, err := NewBlockChain(chaindb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(chaindb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2202,8 +2229,12 @@ func testInsertKnownChainDataWithMerging(t *testing.T, typ string, mergeHeight i
 	// Copy the TestChainConfig so we can modify it during tests
 	chainConfig := *params.TestChainConfig
 	var (
-		db        = rawdb.NewMemoryDatabase()
-		genesis   = (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee), Config: &chainConfig}).MustCommit(db)
+		db    = rawdb.NewMemoryDatabase()
+		gspec = &Genesis{
+			BaseFee: big.NewInt(params.InitialBaseFee),
+			Config:  &chainConfig,
+		}
+		genesis   = gspec.MustCommit(db)
 		runMerger = consensus.NewMerger(db)
 		runEngine = beacon.New(ethash.NewFaker())
 		genEngine = beacon.New(ethash.NewFaker())
@@ -2242,7 +2273,7 @@ func testInsertKnownChainDataWithMerging(t *testing.T, typ string, mergeHeight i
 	(&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(chaindb)
 	defer chaindb.Close()
 
-	chain, err := NewBlockChain(chaindb, nil, &chainConfig, runEngine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(chaindb, nil, gspec, nil, runEngine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2350,7 +2381,11 @@ func getLongAndShortChains() (bc *BlockChain, longChain []*types.Block, heavyCha
 	// Generate a canonical chain to act as the main dataset
 	engine := ethash.NewFaker()
 	db := rawdb.NewMemoryDatabase()
-	genesis := (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+	gspec := &Genesis{
+		BaseFee: big.NewInt(params.InitialBaseFee),
+		Config:  params.TestChainConfig,
+	}
+	genesis := gspec.MustCommit(db)
 
 	// Generate and import the canonical chain,
 	// Offset the time, to keep the difficulty low
@@ -2358,9 +2393,9 @@ func getLongAndShortChains() (bc *BlockChain, longChain []*types.Block, heavyCha
 		b.SetCoinbase(common.Address{1})
 	})
 	diskdb := rawdb.NewMemoryDatabase()
-	(&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(diskdb)
+	gspec.MustCommit(diskdb)
 
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		return nil, nil, nil, fmt.Errorf("failed to create tester chain: %v", err)
 	}
@@ -2390,12 +2425,12 @@ func getLongAndShortChains() (bc *BlockChain, longChain []*types.Block, heavyCha
 		shorterTd.Add(shorterTd, b.Difficulty())
 	}
 	if shorterTd.Cmp(longerTd) <= 0 {
-		return nil, nil, nil, fmt.Errorf("Test is moot, heavyChain td (%v) must be larger than canon td (%v)", shorterTd, longerTd)
+		return nil, nil, nil, fmt.Errorf("test is moot, heavyChain td (%v) must be larger than canon td (%v)", shorterTd, longerTd)
 	}
 	longerNum := longChain[len(longChain)-1].NumberU64()
 	shorterNum := heavyChain[len(heavyChain)-1].NumberU64()
 	if shorterNum >= longerNum {
-		return nil, nil, nil, fmt.Errorf("Test is moot, heavyChain num (%v) must be lower than canon num (%v)", shorterNum, longerNum)
+		return nil, nil, nil, fmt.Errorf("test is moot, heavyChain num (%v) must be lower than canon num (%v)", shorterNum, longerNum)
 	}
 	return chain, longChain, heavyChain, nil
 }
@@ -2549,7 +2584,7 @@ func TestTransactionIndices(t *testing.T) {
 
 	// Import all blocks into ancient db
 	l := uint64(0)
-	chain, err := NewBlockChain(ancientDb, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, &l)
+	chain, err := NewBlockChain(ancientDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, &l)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2575,7 +2610,7 @@ func TestTransactionIndices(t *testing.T) {
 		}
 		gspec.MustCommit(ancientDb)
 		l := l
-		chain, err = NewBlockChain(ancientDb, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, &l)
+		chain, err = NewBlockChain(ancientDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, &l)
 		if err != nil {
 			t.Fatalf("failed to create tester chain: %v", err)
 		}
@@ -2601,7 +2636,7 @@ func TestTransactionIndices(t *testing.T) {
 	tails := []uint64{0, 67 /* 130 - 64 + 1 */, 100 /* 131 - 32 + 1 */, 69 /* 132 - 64 + 1 */, 0}
 	for i, l := range limit {
 		l := l
-		chain, err = NewBlockChain(ancientDb, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, &l)
+		chain, err = NewBlockChain(ancientDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, &l)
 		if err != nil {
 			t.Fatalf("failed to create tester chain: %v", err)
 		}
@@ -2676,7 +2711,7 @@ func TestSkipStaleTxIndicesInSnapSync(t *testing.T) {
 
 	// Import all blocks into ancient db, only HEAD-32 indices are kept.
 	l := uint64(32)
-	chain, err := NewBlockChain(ancientDb, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, &l)
+	chain, err := NewBlockChain(ancientDb, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, &l)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2702,7 +2737,7 @@ func benchmarkLargeNumberOfValueToNonexisting(b *testing.B, numTxs, numBlocks in
 		testBankKey, _  = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
 		testBankAddress = crypto.PubkeyToAddress(testBankKey.PublicKey)
 		bankFunds       = big.NewInt(100000000000000000)
-		gspec           = Genesis{
+		gspec           = &Genesis{
 			Config: params.TestChainConfig,
 			Alloc: GenesisAlloc{
 				testBankAddress: {Balance: bankFunds},
@@ -2740,7 +2775,7 @@ func benchmarkLargeNumberOfValueToNonexisting(b *testing.B, numTxs, numBlocks in
 		diskdb := rawdb.NewMemoryDatabase()
 		gspec.MustCommit(diskdb)
 
-		chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+		chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 		if err != nil {
 			b.Fatalf("failed to create tester chain: %v", err)
 		}
@@ -2815,14 +2850,18 @@ func TestSideImportPrunedBlocks(t *testing.T) {
 	// Generate a canonical chain to act as the main dataset
 	engine := ethash.NewFaker()
 	db := rawdb.NewMemoryDatabase()
-	genesis := (&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(db)
+	gspec := &Genesis{
+		BaseFee: big.NewInt(params.InitialBaseFee),
+		Config:  params.TestChainConfig,
+	}
+	genesis := gspec.MustCommit(db)
 
 	// Generate and import the canonical chain
 	blocks, _ := GenerateChain(params.TestChainConfig, genesis, engine, db, 2*TriesInMemory, nil)
 	diskdb := rawdb.NewMemoryDatabase()
 
-	(&Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}).MustCommit(diskdb)
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+	gspec.MustCommit(diskdb)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -2916,7 +2955,7 @@ func TestDeleteCreateRevert(t *testing.T) {
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
 
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3027,7 +3066,7 @@ func TestDeleteRecreateSlots(t *testing.T) {
 	// Import the canonical chain
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{
 		Debug:  true,
 		Tracer: logger.NewJSONLogger(nil, os.Stdout),
 	}, nil, nil)
@@ -3107,7 +3146,7 @@ func TestDeleteRecreateAccount(t *testing.T) {
 	// Import the canonical chain
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{
 		Debug:  true,
 		Tracer: logger.NewJSONLogger(nil, os.Stdout),
 	}, nil, nil)
@@ -3280,7 +3319,7 @@ func TestDeleteRecreateSlotsAcrossManyBlocks(t *testing.T) {
 	// Import the canonical chain
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{
 		//Debug:  true,
 		//Tracer: vm.NewJSONLogger(nil, os.Stdout),
 	}, nil, nil)
@@ -3414,7 +3453,7 @@ func TestInitThenFailCreateContract(t *testing.T) {
 	// Import the canonical chain
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{
 		//Debug:  true,
 		//Tracer: vm.NewJSONLogger(nil, os.Stdout),
 	}, nil, nil)
@@ -3504,7 +3543,7 @@ func TestEIP2718Transition(t *testing.T) {
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
 
-	chain, err := NewBlockChain(diskdb, nil, gspec.Config, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3598,7 +3637,7 @@ func TestEIP1559Transition(t *testing.T) {
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
 
-	chain, err := NewBlockChain(diskdb, nil, gspec.Config, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3705,7 +3744,7 @@ func TestSetCanonical(t *testing.T) {
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
 
-	chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+	chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -3811,7 +3850,7 @@ func TestCanonicalHashMarker(t *testing.T) {
 		// Initialize test chain
 		diskdb := rawdb.NewMemoryDatabase()
 		gspec.MustCommit(diskdb)
-		chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil, nil)
+		chain, err := NewBlockChain(diskdb, nil, gspec, nil, engine, vm.Config{}, nil, nil)
 		if err != nil {
 			t.Fatalf("failed to create tester chain: %v", err)
 		}
diff --git a/core/chain_makers_test.go b/core/chain_makers_test.go
index 85a029f7c757..166ac3f227fc 100644
--- a/core/chain_makers_test.go
+++ b/core/chain_makers_test.go
@@ -79,7 +79,7 @@ func ExampleGenerateChain() {
 	})
 
 	// Import the chain. This runs all block validation rules.
-	blockchain, _ := NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer blockchain.Stop()
 
 	if i, err := blockchain.InsertChain(chain); err != nil {
diff --git a/core/dao_test.go b/core/dao_test.go
index c9c765a3832a..8089b5470aaf 100644
--- a/core/dao_test.go
+++ b/core/dao_test.go
@@ -30,32 +30,45 @@ import (
 // blocks based on their extradata fields.
 func TestDAOForkRangeExtradata(t *testing.T) {
 	forkBlock := big.NewInt(32)
+	chainConfig := *params.NonActivatedConfig
+	chainConfig.HomesteadBlock = big.NewInt(0)
 
 	// Generate a common prefix for both pro-forkers and non-forkers
 	db := rawdb.NewMemoryDatabase()
-	gspec := &Genesis{BaseFee: big.NewInt(params.InitialBaseFee)}
+	gspec := &Genesis{
+		BaseFee: big.NewInt(params.InitialBaseFee),
+		Config:  &chainConfig,
+	}
 	genesis := gspec.MustCommit(db)
-	prefix, _ := GenerateChain(params.TestChainConfig, genesis, ethash.NewFaker(), db, int(forkBlock.Int64()-1), func(i int, gen *BlockGen) {})
+	prefix, _ := GenerateChain(&chainConfig, genesis, ethash.NewFaker(), db, int(forkBlock.Int64()-1), func(i int, gen *BlockGen) {})
 
 	// Create the concurrent, conflicting two nodes
 	proDb := rawdb.NewMemoryDatabase()
-	gspec.MustCommit(proDb)
-
-	proConf := *params.TestChainConfig
+	proConf := *params.NonActivatedConfig
+	proConf.HomesteadBlock = big.NewInt(0)
 	proConf.DAOForkBlock = forkBlock
 	proConf.DAOForkSupport = true
+	progspec := &Genesis{
+		BaseFee: big.NewInt(params.InitialBaseFee),
+		Config:  &proConf,
+	}
+	gspec.MustCommit(proDb)
 
-	proBc, _ := NewBlockChain(proDb, nil, &proConf, ethash.NewFaker(), vm.Config{}, nil, nil)
+	proBc, _ := NewBlockChain(proDb, nil, progspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer proBc.Stop()
 
 	conDb := rawdb.NewMemoryDatabase()
-	gspec.MustCommit(conDb)
-
-	conConf := *params.TestChainConfig
+	conConf := *params.NonActivatedConfig
+	conConf.HomesteadBlock = big.NewInt(0)
 	conConf.DAOForkBlock = forkBlock
 	conConf.DAOForkSupport = false
+	congspec := &Genesis{
+		BaseFee: big.NewInt(params.InitialBaseFee),
+		Config:  &conConf,
+	}
+	gspec.MustCommit(conDb)
 
-	conBc, _ := NewBlockChain(conDb, nil, &conConf, ethash.NewFaker(), vm.Config{}, nil, nil)
+	conBc, _ := NewBlockChain(conDb, nil, congspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer conBc.Stop()
 
 	if _, err := proBc.InsertChain(prefix); err != nil {
@@ -68,8 +81,8 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 	for i := int64(0); i < params.DAOForkExtraRange.Int64(); i++ {
 		// Create a pro-fork block, and try to feed into the no-fork chain
 		db = rawdb.NewMemoryDatabase()
-		gspec.MustCommit(db)
-		bc, _ := NewBlockChain(db, nil, &conConf, ethash.NewFaker(), vm.Config{}, nil, nil)
+		congspec.MustCommit(db)
+		bc, _ := NewBlockChain(db, nil, congspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 		defer bc.Stop()
 
 		blocks := conBc.GetBlocksFromHash(conBc.CurrentBlock().Hash(), int(conBc.CurrentBlock().NumberU64()))
@@ -93,8 +106,8 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 		}
 		// Create a no-fork block, and try to feed into the pro-fork chain
 		db = rawdb.NewMemoryDatabase()
-		gspec.MustCommit(db)
-		bc, _ = NewBlockChain(db, nil, &proConf, ethash.NewFaker(), vm.Config{}, nil, nil)
+		progspec.MustCommit(db)
+		bc, _ = NewBlockChain(db, nil, progspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 		defer bc.Stop()
 
 		blocks = proBc.GetBlocksFromHash(proBc.CurrentBlock().Hash(), int(proBc.CurrentBlock().NumberU64()))
@@ -119,8 +132,8 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 	}
 	// Verify that contra-forkers accept pro-fork extra-datas after forking finishes
 	db = rawdb.NewMemoryDatabase()
-	gspec.MustCommit(db)
-	bc, _ := NewBlockChain(db, nil, &conConf, ethash.NewFaker(), vm.Config{}, nil, nil)
+	congspec.MustCommit(db)
+	bc, _ := NewBlockChain(db, nil, congspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer bc.Stop()
 
 	blocks := conBc.GetBlocksFromHash(conBc.CurrentBlock().Hash(), int(conBc.CurrentBlock().NumberU64()))
@@ -139,8 +152,8 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 	}
 	// Verify that pro-forkers accept contra-fork extra-datas after forking finishes
 	db = rawdb.NewMemoryDatabase()
-	gspec.MustCommit(db)
-	bc, _ = NewBlockChain(db, nil, &proConf, ethash.NewFaker(), vm.Config{}, nil, nil)
+	progspec.MustCommit(db)
+	bc, _ = NewBlockChain(db, nil, progspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	defer bc.Stop()
 
 	blocks = proBc.GetBlocksFromHash(proBc.CurrentBlock().Hash(), int(proBc.CurrentBlock().NumberU64()))
diff --git a/core/genesis.go b/core/genesis.go
index 71214e84f505..fd692259dc6d 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -211,7 +211,6 @@ func (h *storageJSON) UnmarshalText(text []byte) error {
 	}
 	offset := len(h) - len(text)/2 // pad on the left
 	if _, err := hex.Decode(h[offset:], text); err != nil {
-		fmt.Println(err)
 		return fmt.Errorf("invalid hex storage key/value %q", text)
 	}
 	return nil
@@ -231,6 +230,12 @@ func (e *GenesisMismatchError) Error() string {
 	return fmt.Sprintf("database contains incompatible genesis (have %x, new %x)", e.Stored, e.New)
 }
 
+// ChainOverrides contains the changes to chain config.
+type ChainOverrides struct {
+	OverrideTerminalTotalDifficulty       *big.Int
+	OverrideTerminalTotalDifficultyPassed *bool
+}
+
 // SetupGenesisBlock writes or updates the genesis block in db.
 // The block that will be used is:
 //
@@ -245,21 +250,21 @@ func (e *GenesisMismatchError) Error() string {
 //
 // The returned chain configuration is never nil.
 func SetupGenesisBlock(db ethdb.Database, genesis *Genesis) (*params.ChainConfig, common.Hash, error) {
-	return SetupGenesisBlockWithOverride(db, genesis, nil, nil)
+	return SetupGenesisBlockWithOverride(db, genesis, nil)
 }
 
-func SetupGenesisBlockWithOverride(db ethdb.Database, genesis *Genesis, overrideTerminalTotalDifficulty *big.Int, overrideTerminalTotalDifficultyPassed *bool) (*params.ChainConfig, common.Hash, error) {
+func SetupGenesisBlockWithOverride(db ethdb.Database, genesis *Genesis, overrides *ChainOverrides) (*params.ChainConfig, common.Hash, error) {
 	if genesis != nil && genesis.Config == nil {
 		return params.AllEthashProtocolChanges, common.Hash{}, errGenesisNoConfig
 	}
 
 	applyOverrides := func(config *params.ChainConfig) {
 		if config != nil {
-			if overrideTerminalTotalDifficulty != nil {
-				config.TerminalTotalDifficulty = overrideTerminalTotalDifficulty
+			if overrides != nil && overrides.OverrideTerminalTotalDifficulty != nil {
+				config.TerminalTotalDifficulty = overrides.OverrideTerminalTotalDifficulty
 			}
-			if overrideTerminalTotalDifficultyPassed != nil {
-				config.TerminalTotalDifficultyPassed = *overrideTerminalTotalDifficultyPassed
+			if overrides != nil && overrides.OverrideTerminalTotalDifficultyPassed != nil {
+				config.TerminalTotalDifficultyPassed = *overrides.OverrideTerminalTotalDifficultyPassed
 			}
 		}
 	}
@@ -341,6 +346,42 @@ func SetupGenesisBlockWithOverride(db ethdb.Database, genesis *Genesis, override
 	return newcfg, stored, nil
 }
 
+// LoadCliqueConfig loads the stored clique config if the chain config
+// is already present in database, otherwise, return the config in the
+// provided genesis specification. Note the returned clique config can
+// be nil if we are not in the clique network.
+func LoadCliqueConfig(db ethdb.Database, genesis *Genesis) (*params.CliqueConfig, error) {
+	// Load the stored chain config from the database. It can be nil
+	// in case the database is empty. Notably, we only care about the
+	// chain config corresponds to the canonical chain.
+	stored := rawdb.ReadCanonicalHash(db, 0)
+	if stored != (common.Hash{}) {
+		storedcfg := rawdb.ReadChainConfig(db, stored)
+		if storedcfg != nil {
+			return storedcfg.Clique, nil
+		}
+	}
+	// Load the clique config from the provided genesis specification.
+	if genesis != nil {
+		// Reject invalid genesis spec without valid chain config
+		if genesis.Config == nil {
+			return nil, errGenesisNoConfig
+		}
+		// If the canonical genesis header is present, but the chain
+		// config is missing(initialize the empty leveldb with an
+		// external ancient chain segment), ensure the provided genesis
+		// is matched.
+		if stored != (common.Hash{}) && genesis.ToBlock().Hash() != stored {
+			return nil, &GenesisMismatchError{stored, genesis.ToBlock().Hash()}
+		}
+		return genesis.Config.Clique, nil
+	}
+	// There is no stored chain config and no new config provided,
+	// In this case the default chain config(mainnet) will be used,
+	// namely ethash is the specified consensus engine, return nil.
+	return nil, nil
+}
+
 func (g *Genesis) configOrDefault(ghash common.Hash) *params.ChainConfig {
 	switch {
 	case g != nil:
diff --git a/core/genesis_test.go b/core/genesis_test.go
index ba3423e32a08..a7d04f53fe23 100644
--- a/core/genesis_test.go
+++ b/core/genesis_test.go
@@ -117,7 +117,7 @@ func TestSetupGenesis(t *testing.T) {
 				// Advance to block #4, past the homestead transition block of customg.
 				genesis := oldcustomg.MustCommit(db)
 
-				bc, _ := NewBlockChain(db, nil, oldcustomg.Config, ethash.NewFullFaker(), vm.Config{}, nil, nil)
+				bc, _ := NewBlockChain(db, nil, &oldcustomg, nil, ethash.NewFullFaker(), vm.Config{}, nil, nil)
 				defer bc.Stop()
 
 				blocks, _ := GenerateChain(oldcustomg.Config, genesis, ethash.NewFaker(), db, 4, nil)
diff --git a/core/state_processor_test.go b/core/state_processor_test.go
index aa8e4bebf9d4..42faa28d058f 100644
--- a/core/state_processor_test.go
+++ b/core/state_processor_test.go
@@ -92,7 +92,7 @@ func TestStateProcessorErrors(t *testing.T) {
 				},
 			}
 			genesis       = gspec.MustCommit(db)
-			blockchain, _ = NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+			blockchain, _ = NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 		)
 		defer blockchain.Stop()
 		bigNumber := new(big.Int).SetBytes(common.FromHex("0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"))
@@ -233,7 +233,7 @@ func TestStateProcessorErrors(t *testing.T) {
 				},
 			}
 			genesis       = gspec.MustCommit(db)
-			blockchain, _ = NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+			blockchain, _ = NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 		)
 		defer blockchain.Stop()
 		for i, tt := range []struct {
@@ -273,7 +273,7 @@ func TestStateProcessorErrors(t *testing.T) {
 				},
 			}
 			genesis       = gspec.MustCommit(db)
-			blockchain, _ = NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+			blockchain, _ = NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 		)
 		defer blockchain.Stop()
 		for i, tt := range []struct {
diff --git a/eth/backend.go b/eth/backend.go
index ebe7001c7994..243c5dd4e6b7 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -22,7 +22,6 @@ import (
 	"fmt"
 	"math/big"
 	"runtime"
-	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -128,38 +127,30 @@ func New(stack *node.Node, config *ethconfig.Config) (*Ethereum, error) {
 	}
 	log.Info("Allocated trie memory caches", "clean", common.StorageSize(config.TrieCleanCache)*1024*1024, "dirty", common.StorageSize(config.TrieDirtyCache)*1024*1024)
 
-	// Transfer mining-related config to the ethash config.
-	ethashConfig := config.Ethash
-	ethashConfig.NotifyFull = config.Miner.NotifyFull
-
 	// Assemble the Ethereum object
 	chainDb, err := stack.OpenDatabaseWithFreezer("chaindata", config.DatabaseCache, config.DatabaseHandles, config.DatabaseFreezer, "eth/db/chaindata/", false)
 	if err != nil {
 		return nil, err
 	}
-	chainConfig, genesisHash, genesisErr := core.SetupGenesisBlockWithOverride(chainDb, config.Genesis, config.OverrideTerminalTotalDifficulty, config.OverrideTerminalTotalDifficultyPassed)
-	if _, ok := genesisErr.(*params.ConfigCompatError); genesisErr != nil && !ok {
-		return nil, genesisErr
-	}
-	log.Info("")
-	log.Info(strings.Repeat("-", 153))
-	for _, line := range strings.Split(chainConfig.String(), "\n") {
-		log.Info(line)
-	}
-	log.Info(strings.Repeat("-", 153))
-	log.Info("")
-
 	if err := pruner.RecoverPruning(stack.ResolvePath(""), chainDb, stack.ResolvePath(config.TrieCleanCacheJournal)); err != nil {
 		log.Error("Failed to recover state", "error", err)
 	}
-	merger := consensus.NewMerger(chainDb)
+	// Transfer mining-related config to the ethash config.
+	ethashConfig := config.Ethash
+	ethashConfig.NotifyFull = config.Miner.NotifyFull
+	cliqueConfig, err := core.LoadCliqueConfig(chainDb, config.Genesis)
+	if err != nil {
+		return nil, err
+	}
+	engine := ethconfig.CreateConsensusEngine(stack, &ethashConfig, cliqueConfig, config.Miner.Notify, config.Miner.Noverify, chainDb)
+
 	eth := &Ethereum{
 		config:            config,
-		merger:            merger,
+		merger:            consensus.NewMerger(chainDb),
 		chainDb:           chainDb,
 		eventMux:          stack.EventMux(),
 		accountManager:    stack.AccountManager(),
-		engine:            ethconfig.CreateConsensusEngine(stack, chainConfig, &ethashConfig, config.Miner.Notify, config.Miner.Noverify, chainDb),
+		engine:            engine,
 		closeBloomHandler: make(chan struct{}),
 		networkID:         config.NetworkId,
 		gasPrice:          config.Miner.GasPrice,
@@ -203,34 +194,36 @@ func New(stack *node.Node, config *ethconfig.Config) (*Ethereum, error) {
 			Preimages:           config.Preimages,
 		}
 	)
-	eth.blockchain, err = core.NewBlockChain(chainDb, cacheConfig, chainConfig, eth.engine, vmConfig, eth.shouldPreserve, &config.TxLookupLimit)
+	// Override the chain config with provided settings.
+	var overrides core.ChainOverrides
+	if config.OverrideTerminalTotalDifficulty != nil {
+		overrides.OverrideTerminalTotalDifficulty = config.OverrideTerminalTotalDifficulty
+	}
+	if config.OverrideTerminalTotalDifficultyPassed != nil {
+		overrides.OverrideTerminalTotalDifficultyPassed = config.OverrideTerminalTotalDifficultyPassed
+	}
+	eth.blockchain, err = core.NewBlockChain(chainDb, cacheConfig, config.Genesis, &overrides, eth.engine, vmConfig, eth.shouldPreserve, &config.TxLookupLimit)
 	if err != nil {
 		return nil, err
 	}
-	// Rewind the chain in case of an incompatible config upgrade.
-	if compat, ok := genesisErr.(*params.ConfigCompatError); ok {
-		log.Warn("Rewinding chain to upgrade configuration", "err", compat)
-		eth.blockchain.SetHead(compat.RewindTo)
-		rawdb.WriteChainConfig(chainDb, genesisHash, chainConfig)
-	}
 	eth.bloomIndexer.Start(eth.blockchain)
 
 	if config.TxPool.Journal != "" {
 		config.TxPool.Journal = stack.ResolvePath(config.TxPool.Journal)
 	}
-	eth.txPool = core.NewTxPool(config.TxPool, chainConfig, eth.blockchain)
+	eth.txPool = core.NewTxPool(config.TxPool, eth.blockchain.Config(), eth.blockchain)
 
 	// Permit the downloader to use the trie cache allowance during fast sync
 	cacheLimit := cacheConfig.TrieCleanLimit + cacheConfig.TrieDirtyLimit + cacheConfig.SnapshotLimit
 	checkpoint := config.Checkpoint
 	if checkpoint == nil {
-		checkpoint = params.TrustedCheckpoints[genesisHash]
+		checkpoint = params.TrustedCheckpoints[eth.blockchain.Genesis().Hash()]
 	}
 	if eth.handler, err = newHandler(&handlerConfig{
 		Database:       chainDb,
 		Chain:          eth.blockchain,
 		TxPool:         eth.txPool,
-		Merger:         merger,
+		Merger:         eth.merger,
 		Network:        config.NetworkId,
 		Sync:           config.SyncMode,
 		BloomCache:     uint64(cacheLimit),
@@ -241,7 +234,7 @@ func New(stack *node.Node, config *ethconfig.Config) (*Ethereum, error) {
 		return nil, err
 	}
 
-	eth.miner = miner.New(eth, &config.Miner, chainConfig, eth.EventMux(), eth.engine, eth.isLocalBlock)
+	eth.miner = miner.New(eth, &config.Miner, eth.blockchain.Config(), eth.EventMux(), eth.engine, eth.isLocalBlock)
 	eth.miner.SetExtra(makeExtraData(config.Miner.ExtraData))
 
 	eth.APIBackend = &EthAPIBackend{stack.Config().ExtRPCEnabled(), stack.Config().AllowUnprotectedTxs, eth, nil}
diff --git a/eth/downloader/downloader_test.go b/eth/downloader/downloader_test.go
index 1c126bdaed38..013452a54014 100644
--- a/eth/downloader/downloader_test.go
+++ b/eth/downloader/downloader_test.go
@@ -68,13 +68,14 @@ func newTesterWithNotification(t *testing.T, success func()) *downloadTester {
 	t.Cleanup(func() {
 		db.Close()
 	})
-	gspec := core.Genesis{
+	gspec := &core.Genesis{
+		Config:  params.TestChainConfig,
 		Alloc:   core.GenesisAlloc{testAddress: {Balance: big.NewInt(1000000000000000)}},
 		BaseFee: big.NewInt(params.InitialBaseFee),
 	}
 	gspec.MustCommit(db)
 
-	chain, err := core.NewBlockChain(db, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	if err != nil {
 		panic(err)
 	}
diff --git a/eth/downloader/testchain_test.go b/eth/downloader/testchain_test.go
index 785da40b5989..1c96681e2f5b 100644
--- a/eth/downloader/testchain_test.go
+++ b/eth/downloader/testchain_test.go
@@ -39,6 +39,7 @@ var (
 	testDB      = rawdb.NewMemoryDatabase()
 
 	testGspec = core.Genesis{
+		Config:  params.TestChainConfig,
 		Alloc:   core.GenesisAlloc{testAddress: {Balance: big.NewInt(1000000000000000)}},
 		BaseFee: big.NewInt(params.InitialBaseFee),
 	}
@@ -219,7 +220,7 @@ func newTestBlockchain(blocks []*types.Block) *core.BlockChain {
 		db := rawdb.NewMemoryDatabase()
 		testGspec.MustCommit(db)
 
-		chain, err := core.NewBlockChain(db, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, nil)
+		chain, err := core.NewBlockChain(db, nil, &testGspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 		if err != nil {
 			panic(err)
 		}
diff --git a/eth/ethconfig/config.go b/eth/ethconfig/config.go
index 7ba2faf791b4..6d271171f47c 100644
--- a/eth/ethconfig/config.go
+++ b/eth/ethconfig/config.go
@@ -213,13 +213,13 @@ type Config struct {
 }
 
 // CreateConsensusEngine creates a consensus engine for the given chain configuration.
-func CreateConsensusEngine(stack *node.Node, chainConfig *params.ChainConfig, config *ethash.Config, notify []string, noverify bool, db ethdb.Database) consensus.Engine {
+func CreateConsensusEngine(stack *node.Node, ethashConfig *ethash.Config, cliqueConfig *params.CliqueConfig, notify []string, noverify bool, db ethdb.Database) consensus.Engine {
 	// If proof-of-authority is requested, set it up
 	var engine consensus.Engine
-	if chainConfig.Clique != nil {
-		engine = clique.New(chainConfig.Clique, db)
+	if cliqueConfig != nil {
+		engine = clique.New(cliqueConfig, db)
 	} else {
-		switch config.PowMode {
+		switch ethashConfig.PowMode {
 		case ethash.ModeFake:
 			log.Warn("Ethash used in fake mode")
 		case ethash.ModeTest:
@@ -228,16 +228,16 @@ func CreateConsensusEngine(stack *node.Node, chainConfig *params.ChainConfig, co
 			log.Warn("Ethash used in shared mode")
 		}
 		engine = ethash.New(ethash.Config{
-			PowMode:          config.PowMode,
-			CacheDir:         stack.ResolvePath(config.CacheDir),
-			CachesInMem:      config.CachesInMem,
-			CachesOnDisk:     config.CachesOnDisk,
-			CachesLockMmap:   config.CachesLockMmap,
-			DatasetDir:       config.DatasetDir,
-			DatasetsInMem:    config.DatasetsInMem,
-			DatasetsOnDisk:   config.DatasetsOnDisk,
-			DatasetsLockMmap: config.DatasetsLockMmap,
-			NotifyFull:       config.NotifyFull,
+			PowMode:          ethashConfig.PowMode,
+			CacheDir:         stack.ResolvePath(ethashConfig.CacheDir),
+			CachesInMem:      ethashConfig.CachesInMem,
+			CachesOnDisk:     ethashConfig.CachesOnDisk,
+			CachesLockMmap:   ethashConfig.CachesLockMmap,
+			DatasetDir:       ethashConfig.DatasetDir,
+			DatasetsInMem:    ethashConfig.DatasetsInMem,
+			DatasetsOnDisk:   ethashConfig.DatasetsOnDisk,
+			DatasetsLockMmap: ethashConfig.DatasetsLockMmap,
+			NotifyFull:       ethashConfig.NotifyFull,
 		}, notify, noverify)
 		engine.(*ethash.Ethash).SetThreads(-1) // Disable CPU mining
 	}
diff --git a/eth/gasprice/gasprice_test.go b/eth/gasprice/gasprice_test.go
index d405188f8194..5830312fd139 100644
--- a/eth/gasprice/gasprice_test.go
+++ b/eth/gasprice/gasprice_test.go
@@ -162,7 +162,7 @@ func newTestBackend(t *testing.T, londonBlock *big.Int, pending bool) *testBacke
 	// Construct testing chain
 	diskdb := rawdb.NewMemoryDatabase()
 	gspec.MustCommit(diskdb)
-	chain, err := core.NewBlockChain(diskdb, &core.CacheConfig{TrieCleanNoPrefetch: true}, gspec.Config, engine, vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(diskdb, &core.CacheConfig{TrieCleanNoPrefetch: true}, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("Failed to create local chain, %v", err)
 	}
diff --git a/eth/handler_eth_test.go b/eth/handler_eth_test.go
index 453bc5e98e31..9c2fcd36f7ab 100644
--- a/eth/handler_eth_test.go
+++ b/eth/handler_eth_test.go
@@ -105,8 +105,8 @@ func testForkIDSplit(t *testing.T, protocol uint) {
 		genesisNoFork  = gspecNoFork.MustCommit(dbNoFork)
 		genesisProFork = gspecProFork.MustCommit(dbProFork)
 
-		chainNoFork, _  = core.NewBlockChain(dbNoFork, nil, configNoFork, engine, vm.Config{}, nil, nil)
-		chainProFork, _ = core.NewBlockChain(dbProFork, nil, configProFork, engine, vm.Config{}, nil, nil)
+		chainNoFork, _  = core.NewBlockChain(dbNoFork, nil, gspecNoFork, nil, engine, vm.Config{}, nil, nil)
+		chainProFork, _ = core.NewBlockChain(dbProFork, nil, gspecProFork, nil, engine, vm.Config{}, nil, nil)
 
 		blocksNoFork, _  = core.GenerateChain(configNoFork, genesisNoFork, engine, dbNoFork, 2, nil)
 		blocksProFork, _ = core.GenerateChain(configProFork, genesisProFork, engine, dbProFork, 2, nil)
diff --git a/eth/handler_test.go b/eth/handler_test.go
index d967b6df935e..044130f40f8c 100644
--- a/eth/handler_test.go
+++ b/eth/handler_test.go
@@ -133,12 +133,13 @@ func newTestHandler() *testHandler {
 func newTestHandlerWithBlocks(blocks int) *testHandler {
 	// Create a database pre-initialize with a genesis block
 	db := rawdb.NewMemoryDatabase()
-	(&core.Genesis{
+	gspec := &core.Genesis{
 		Config: params.TestChainConfig,
 		Alloc:  core.GenesisAlloc{testAddr: {Balance: big.NewInt(1000000)}},
-	}).MustCommit(db)
+	}
+	gspec.MustCommit(db)
 
-	chain, _ := core.NewBlockChain(db, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chain, _ := core.NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 
 	bs, _ := core.GenerateChain(params.TestChainConfig, chain.Genesis(), ethash.NewFaker(), db, blocks, nil)
 	if _, err := chain.InsertChain(bs); err != nil {
diff --git a/eth/protocols/eth/handler_test.go b/eth/protocols/eth/handler_test.go
index bf836e8f5132..844c5887f793 100644
--- a/eth/protocols/eth/handler_test.go
+++ b/eth/protocols/eth/handler_test.go
@@ -63,12 +63,13 @@ func newTestBackend(blocks int) *testBackend {
 func newTestBackendWithGenerator(blocks int, generator func(int, *core.BlockGen)) *testBackend {
 	// Create a database pre-initialize with a genesis block
 	db := rawdb.NewMemoryDatabase()
-	(&core.Genesis{
+	gspec := &core.Genesis{
 		Config: params.TestChainConfig,
 		Alloc:  core.GenesisAlloc{testAddr: {Balance: big.NewInt(100_000_000_000_000_000)}},
-	}).MustCommit(db)
+	}
+	gspec.MustCommit(db)
 
-	chain, _ := core.NewBlockChain(db, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, nil)
+	chain, _ := core.NewBlockChain(db, nil, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 
 	bs, _ := core.GenerateChain(params.TestChainConfig, chain.Genesis(), ethash.NewFaker(), db, blocks, generator)
 	if _, err := chain.InsertChain(bs); err != nil {
diff --git a/eth/tracers/api_test.go b/eth/tracers/api_test.go
index bc12b9275160..b75b6793592c 100644
--- a/eth/tracers/api_test.go
+++ b/eth/tracers/api_test.go
@@ -82,7 +82,7 @@ func newTestBackend(t *testing.T, n int, gspec *core.Genesis, generator func(i i
 		SnapshotLimit:     0,
 		TrieDirtyDisabled: true, // Archive mode
 	}
-	chain, err := core.NewBlockChain(backend.chaindb, cacheConfig, backend.chainConfig, backend.engine, vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(backend.chaindb, cacheConfig, gspec, nil, backend.engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("failed to create tester chain: %v", err)
 	}
@@ -182,11 +182,14 @@ func TestTraceCall(t *testing.T) {
 
 	// Initialize test accounts
 	accounts := newAccounts(3)
-	genesis := &core.Genesis{Alloc: core.GenesisAlloc{
-		accounts[0].addr: {Balance: big.NewInt(params.Ether)},
-		accounts[1].addr: {Balance: big.NewInt(params.Ether)},
-		accounts[2].addr: {Balance: big.NewInt(params.Ether)},
-	}}
+	genesis := &core.Genesis{
+		Config: params.TestChainConfig,
+		Alloc: core.GenesisAlloc{
+			accounts[0].addr: {Balance: big.NewInt(params.Ether)},
+			accounts[1].addr: {Balance: big.NewInt(params.Ether)},
+			accounts[2].addr: {Balance: big.NewInt(params.Ether)},
+		},
+	}
 	genBlocks := 10
 	signer := types.HomesteadSigner{}
 	api := NewAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
@@ -312,10 +315,13 @@ func TestTraceTransaction(t *testing.T) {
 
 	// Initialize test accounts
 	accounts := newAccounts(2)
-	genesis := &core.Genesis{Alloc: core.GenesisAlloc{
-		accounts[0].addr: {Balance: big.NewInt(params.Ether)},
-		accounts[1].addr: {Balance: big.NewInt(params.Ether)},
-	}}
+	genesis := &core.Genesis{
+		Config: params.TestChainConfig,
+		Alloc: core.GenesisAlloc{
+			accounts[0].addr: {Balance: big.NewInt(params.Ether)},
+			accounts[1].addr: {Balance: big.NewInt(params.Ether)},
+		},
+	}
 	target := common.Hash{}
 	signer := types.HomesteadSigner{}
 	api := NewAPI(newTestBackend(t, 1, genesis, func(i int, b *core.BlockGen) {
@@ -349,11 +355,14 @@ func TestTraceBlock(t *testing.T) {
 
 	// Initialize test accounts
 	accounts := newAccounts(3)
-	genesis := &core.Genesis{Alloc: core.GenesisAlloc{
-		accounts[0].addr: {Balance: big.NewInt(params.Ether)},
-		accounts[1].addr: {Balance: big.NewInt(params.Ether)},
-		accounts[2].addr: {Balance: big.NewInt(params.Ether)},
-	}}
+	genesis := &core.Genesis{
+		Config: params.TestChainConfig,
+		Alloc: core.GenesisAlloc{
+			accounts[0].addr: {Balance: big.NewInt(params.Ether)},
+			accounts[1].addr: {Balance: big.NewInt(params.Ether)},
+			accounts[2].addr: {Balance: big.NewInt(params.Ether)},
+		},
+	}
 	genBlocks := 10
 	signer := types.HomesteadSigner{}
 	api := NewAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
@@ -424,11 +433,14 @@ func TestTracingWithOverrides(t *testing.T) {
 	t.Parallel()
 	// Initialize test accounts
 	accounts := newAccounts(3)
-	genesis := &core.Genesis{Alloc: core.GenesisAlloc{
-		accounts[0].addr: {Balance: big.NewInt(params.Ether)},
-		accounts[1].addr: {Balance: big.NewInt(params.Ether)},
-		accounts[2].addr: {Balance: big.NewInt(params.Ether)},
-	}}
+	genesis := &core.Genesis{
+		Config: params.TestChainConfig,
+		Alloc: core.GenesisAlloc{
+			accounts[0].addr: {Balance: big.NewInt(params.Ether)},
+			accounts[1].addr: {Balance: big.NewInt(params.Ether)},
+			accounts[2].addr: {Balance: big.NewInt(params.Ether)},
+		},
+	}
 	genBlocks := 10
 	signer := types.HomesteadSigner{}
 	api := NewAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
diff --git a/les/client.go b/les/client.go
index 7caaf2c18a58..ff810f0843c2 100644
--- a/les/client.go
+++ b/les/client.go
@@ -93,7 +93,14 @@ func New(stack *node.Node, config *ethconfig.Config) (*LightEthereum, error) {
 	if err != nil {
 		return nil, err
 	}
-	chainConfig, genesisHash, genesisErr := core.SetupGenesisBlockWithOverride(chainDb, config.Genesis, config.OverrideTerminalTotalDifficulty, config.OverrideTerminalTotalDifficultyPassed)
+	var overrides core.ChainOverrides
+	if config.OverrideTerminalTotalDifficulty != nil {
+		overrides.OverrideTerminalTotalDifficulty = config.OverrideTerminalTotalDifficulty
+	}
+	if config.OverrideTerminalTotalDifficultyPassed != nil {
+		overrides.OverrideTerminalTotalDifficultyPassed = config.OverrideTerminalTotalDifficultyPassed
+	}
+	chainConfig, genesisHash, genesisErr := core.SetupGenesisBlockWithOverride(chainDb, config.Genesis, &overrides)
 	if _, isCompat := genesisErr.(*params.ConfigCompatError); genesisErr != nil && !isCompat {
 		return nil, genesisErr
 	}
@@ -122,7 +129,7 @@ func New(stack *node.Node, config *ethconfig.Config) (*LightEthereum, error) {
 		reqDist:         newRequestDistributor(peers, &mclock.System{}),
 		accountManager:  stack.AccountManager(),
 		merger:          merger,
-		engine:          ethconfig.CreateConsensusEngine(stack, chainConfig, &config.Ethash, nil, false, chainDb),
+		engine:          ethconfig.CreateConsensusEngine(stack, &config.Ethash, chainConfig.Clique, nil, false, chainDb),
 		bloomRequests:   make(chan chan *bloombits.Retrieval),
 		bloomIndexer:    core.NewBloomIndexer(chainDb, params.BloomBitsBlocksClient, params.HelperTrieConfirmations),
 		p2pServer:       stack.Server(),
diff --git a/light/odr_test.go b/light/odr_test.go
index ec109f61f2bf..d08963af6628 100644
--- a/light/odr_test.go
+++ b/light/odr_test.go
@@ -253,7 +253,8 @@ func testChainOdr(t *testing.T, protocol int, fn odrTestFn) {
 	var (
 		sdb   = rawdb.NewMemoryDatabase()
 		ldb   = rawdb.NewMemoryDatabase()
-		gspec = core.Genesis{
+		gspec = &core.Genesis{
+			Config:  params.TestChainConfig,
 			Alloc:   core.GenesisAlloc{testBankAddress: {Balance: testBankFunds}},
 			BaseFee: big.NewInt(params.InitialBaseFee),
 		}
@@ -261,7 +262,7 @@ func testChainOdr(t *testing.T, protocol int, fn odrTestFn) {
 	)
 	gspec.MustCommit(ldb)
 	// Assemble the test environment
-	blockchain, _ := core.NewBlockChain(sdb, nil, params.TestChainConfig, ethash.NewFullFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := core.NewBlockChain(sdb, nil, gspec, nil, ethash.NewFullFaker(), vm.Config{}, nil, nil)
 	gchain, _ := core.GenerateChain(params.TestChainConfig, genesis, ethash.NewFaker(), sdb, 4, testChainGen)
 	if _, err := blockchain.InsertChain(gchain); err != nil {
 		t.Fatal(err)
diff --git a/light/trie_test.go b/light/trie_test.go
index 63dd9020f20c..581469c41f49 100644
--- a/light/trie_test.go
+++ b/light/trie_test.go
@@ -37,14 +37,15 @@ func TestNodeIterator(t *testing.T) {
 	var (
 		fulldb  = rawdb.NewMemoryDatabase()
 		lightdb = rawdb.NewMemoryDatabase()
-		gspec   = core.Genesis{
+		gspec   = &core.Genesis{
+			Config:  params.TestChainConfig,
 			Alloc:   core.GenesisAlloc{testBankAddress: {Balance: testBankFunds}},
 			BaseFee: big.NewInt(params.InitialBaseFee),
 		}
 		genesis = gspec.MustCommit(fulldb)
 	)
 	gspec.MustCommit(lightdb)
-	blockchain, _ := core.NewBlockChain(fulldb, nil, params.TestChainConfig, ethash.NewFullFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := core.NewBlockChain(fulldb, nil, gspec, nil, ethash.NewFullFaker(), vm.Config{}, nil, nil)
 	gchain, _ := core.GenerateChain(params.TestChainConfig, genesis, ethash.NewFaker(), fulldb, 4, testChainGen)
 	if _, err := blockchain.InsertChain(gchain); err != nil {
 		panic(err)
diff --git a/light/txpool_test.go b/light/txpool_test.go
index cc2651d29ae5..78cac513cbaf 100644
--- a/light/txpool_test.go
+++ b/light/txpool_test.go
@@ -83,7 +83,8 @@ func TestTxPool(t *testing.T) {
 	var (
 		sdb   = rawdb.NewMemoryDatabase()
 		ldb   = rawdb.NewMemoryDatabase()
-		gspec = core.Genesis{
+		gspec = &core.Genesis{
+			Config:  params.TestChainConfig,
 			Alloc:   core.GenesisAlloc{testBankAddress: {Balance: testBankFunds}},
 			BaseFee: big.NewInt(params.InitialBaseFee),
 		}
@@ -91,7 +92,7 @@ func TestTxPool(t *testing.T) {
 	)
 	gspec.MustCommit(ldb)
 	// Assemble the test environment
-	blockchain, _ := core.NewBlockChain(sdb, nil, params.TestChainConfig, ethash.NewFullFaker(), vm.Config{}, nil, nil)
+	blockchain, _ := core.NewBlockChain(sdb, nil, gspec, nil, ethash.NewFullFaker(), vm.Config{}, nil, nil)
 	gchain, _ := core.GenerateChain(params.TestChainConfig, genesis, ethash.NewFaker(), sdb, poolTestBlocks, txPoolTestChainGen)
 	if _, err := blockchain.InsertChain(gchain); err != nil {
 		panic(err)
diff --git a/miner/miner_test.go b/miner/miner_test.go
index 5bf344fd7076..d49c07d964ca 100644
--- a/miner/miner_test.go
+++ b/miner/miner_test.go
@@ -256,7 +256,7 @@ func createMiner(t *testing.T) (*Miner, *event.TypeMux, func(skipMiner bool)) {
 	// Create consensus engine
 	engine := clique.New(chainConfig.Clique, chainDB)
 	// Create Ethereum backend
-	bc, err := core.NewBlockChain(chainDB, nil, chainConfig, engine, vm.Config{}, nil, nil)
+	bc, err := core.NewBlockChain(chainDB, nil, genesis, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		t.Fatalf("can't create new chain %v", err)
 	}
diff --git a/miner/worker_test.go b/miner/worker_test.go
index bda0fd4899b0..a69daa1164e5 100644
--- a/miner/worker_test.go
+++ b/miner/worker_test.go
@@ -136,7 +136,7 @@ func newTestWorkerBackend(t *testing.T, chainConfig *params.ChainConfig, engine
 	}
 	genesis := gspec.MustCommit(db)
 
-	chain, _ := core.NewBlockChain(db, &core.CacheConfig{TrieDirtyDisabled: true}, gspec.Config, engine, vm.Config{}, nil, nil)
+	chain, _ := core.NewBlockChain(db, &core.CacheConfig{TrieDirtyDisabled: true}, &gspec, nil, engine, vm.Config{}, nil, nil)
 	txpool := core.NewTxPool(testTxPoolConfig, chainConfig, chain)
 
 	// Generate a small n-block chain and an uncle block for it
@@ -236,7 +236,7 @@ func testGenerateBlockAndImport(t *testing.T, isClique bool) {
 	// This test chain imports the mined blocks.
 	db2 := rawdb.NewMemoryDatabase()
 	b.genesis.MustCommit(db2)
-	chain, _ := core.NewBlockChain(db2, nil, b.chain.Config(), engine, vm.Config{}, nil, nil)
+	chain, _ := core.NewBlockChain(db2, nil, b.genesis, nil, engine, vm.Config{}, nil, nil)
 	defer chain.Stop()
 
 	// Ignore empty commit here for less noise.
diff --git a/params/config.go b/params/config.go
index fda4c1aecda3..0d0c9708f8ed 100644
--- a/params/config.go
+++ b/params/config.go
@@ -274,8 +274,9 @@ var (
 	// adding flags to the config to also have to set these fields.
 	AllCliqueProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, nil, nil, nil, nil, false, nil, &CliqueConfig{Period: 0, Epoch: 30000}}
 
-	TestChainConfig = &ChainConfig{big.NewInt(1), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, nil, nil, false, new(EthashConfig), nil}
-	TestRules       = TestChainConfig.Rules(new(big.Int), false)
+	TestChainConfig    = &ChainConfig{big.NewInt(1), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, nil, nil, false, new(EthashConfig), nil}
+	NonActivatedConfig = &ChainConfig{big.NewInt(1), nil, nil, false, nil, common.Hash{}, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, false, new(EthashConfig), nil}
+	TestRules          = TestChainConfig.Rules(new(big.Int), false)
 )
 
 // NetworkNames are user friendly names to use in the chain spec banner.
diff --git a/tests/block_test_util.go b/tests/block_test_util.go
index 76f0b880b4a8..80f93d7c08b3 100644
--- a/tests/block_test_util.go
+++ b/tests/block_test_util.go
@@ -106,7 +106,8 @@ func (t *BlockTest) Run(snapshotter bool) error {
 
 	// import pre accounts & construct test genesis block & state root
 	db := rawdb.NewMemoryDatabase()
-	gblock, err := t.genesis(config).Commit(db)
+	gspec := t.genesis(config)
+	gblock, err := gspec.Commit(db)
 	if err != nil {
 		return err
 	}
@@ -127,7 +128,7 @@ func (t *BlockTest) Run(snapshotter bool) error {
 		cache.SnapshotLimit = 1
 		cache.SnapshotWait = true
 	}
-	chain, err := core.NewBlockChain(db, cache, config, engine, vm.Config{}, nil, nil)
+	chain, err := core.NewBlockChain(db, cache, gspec, nil, engine, vm.Config{}, nil, nil)
 	if err != nil {
 		return err
 	}
diff --git a/tests/fuzzers/les/les-fuzzer.go b/tests/fuzzers/les/les-fuzzer.go
index 677702208871..bb50da2bd841 100644
--- a/tests/fuzzers/les/les-fuzzer.go
+++ b/tests/fuzzers/les/les-fuzzer.go
@@ -80,7 +80,7 @@ func makechain() (bc *core.BlockChain, addrHashes, txHashes []common.Hash) {
 			addrHashes = append(addrHashes, crypto.Keccak256Hash(addr[:]))
 			txHashes = append(txHashes, tx.Hash())
 		})
-	bc, _ = core.NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	bc, _ = core.NewBlockChain(db, nil, &gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	if _, err := bc.InsertChain(blocks); err != nil {
 		panic(err)
 	}
diff --git a/tests/fuzzers/snap/fuzz_handler.go b/tests/fuzzers/snap/fuzz_handler.go
index 1ae61df29dc7..6c370b043e72 100644
--- a/tests/fuzzers/snap/fuzz_handler.go
+++ b/tests/fuzzers/snap/fuzz_handler.go
@@ -62,7 +62,7 @@ func getChain() *core.BlockChain {
 		}
 		ga[common.BytesToAddress(a)] = acc
 	}
-	gspec := core.Genesis{
+	gspec := &core.Genesis{
 		Config: params.TestChainConfig,
 		Alloc:  ga,
 	}
@@ -79,7 +79,7 @@ func getChain() *core.BlockChain {
 		SnapshotWait:        true,
 	}
 	trieRoot = blocks[len(blocks)-1].Root()
-	bc, _ := core.NewBlockChain(db, cacheConf, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+	bc, _ := core.NewBlockChain(db, cacheConf, gspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
 	if _, err := bc.InsertChain(blocks); err != nil {
 		panic(err)
 	}