diff --git a/Makefile b/Makefile
index 278ae63120..857cb8c978 100644
--- a/Makefile
+++ b/Makefile
@@ -2,31 +2,35 @@
 # with Go source code. If you know what GOPATH is then you probably
 # don't need to bother with make.
 
-.PHONY: geth all test lint clean devtools help
+.PHONY: geth all test lint fmt clean devtools help
 
 GOBIN = ./build/bin
 GO ?= latest
 GORUN = go run
 
-#? geth: Build geth
+#? geth: Build geth.
 geth:
 	$(GORUN) build/ci.go install ./cmd/geth
 	@echo "Done building."
 	@echo "Run \"$(GOBIN)/geth\" to launch geth."
 
-#? all: Build all packages and executables
+#? all: Build all packages and executables.
 all:
 	$(GORUN) build/ci.go install
 
-#? test: Run the tests
+#? test: Run the tests.
 test: all
 	$(GORUN) build/ci.go test
 
-#? lint: Run certain pre-selected linters
+#? lint: Run certain pre-selected linters.
 lint: ## Run linters.
 	$(GORUN) build/ci.go lint
 
-#? clean: Clean go cache, built executables, and the auto generated folder
+#? fmt: Ensure consistent code formatting.
+fmt:
+	gofmt -s -w $(shell find . -name "*.go")
+
+#? clean: Clean go cache, built executables, and the auto generated folder.
 clean:
 	go clean -cache
 	rm -fr build/_workspace/pkg/ $(GOBIN)/*
@@ -34,7 +38,7 @@ clean:
 # The devtools target installs tools required for 'go generate'.
 # You need to put $GOBIN (or $GOPATH/bin) in your PATH to use 'go generate'.
 
-#? devtools: Install recommended developer tools
+#? devtools: Install recommended developer tools.
 devtools:
 	env GOBIN= go install golang.org/x/tools/cmd/stringer@latest
 	env GOBIN= go install github.com/fjl/gencodec@latest
@@ -45,5 +49,9 @@ devtools:
 
 #? help: Get more info on make commands.
 help: Makefile
-	@echo " Choose a command run in go-ethereum:"
+	@echo ''
+	@echo 'Usage:'
+	@echo '  make [target]'
+	@echo ''
+	@echo 'Targets:'
 	@sed -n 's/^#?//p' $< | column -t -s ':' |  sort | sed -e 's/^/ /'
diff --git a/eth/tracers/api.go b/eth/tracers/api.go
index 30648c4753..51b55ffdbb 100644
--- a/eth/tracers/api.go
+++ b/eth/tracers/api.go
@@ -804,9 +804,13 @@ func (api *API) standardTraceBlockToFile(ctx context.Context, block *types.Block
 		// Execute the transaction and flush any traces to disk
 		vmenv := vm.NewEVM(vmctx, txContext, statedb, chainConfig, vmConf)
 		statedb.SetTxContext(tx.Hash(), i)
-		vmConf.Tracer.OnTxStart(vmenv.GetVMContext(), tx, msg.From)
+		if vmConf.Tracer.OnTxStart != nil {
+			vmConf.Tracer.OnTxStart(vmenv.GetVMContext(), tx, msg.From)
+		}
 		vmRet, err := core.ApplyMessage(vmenv, msg, new(core.GasPool).AddGas(msg.GasLimit))
-		vmConf.Tracer.OnTxEnd(&types.Receipt{GasUsed: vmRet.UsedGas}, err)
+		if vmConf.Tracer.OnTxEnd != nil {
+			vmConf.Tracer.OnTxEnd(&types.Receipt{GasUsed: vmRet.UsedGas}, err)
+		}
 		if writer != nil {
 			writer.Flush()
 		}
diff --git a/eth/tracers/logger/logger_json.go b/eth/tracers/logger/logger_json.go
index d66b8c4b8a..797f7ac658 100644
--- a/eth/tracers/logger/logger_json.go
+++ b/eth/tracers/logger/logger_json.go
@@ -58,6 +58,7 @@ type jsonLogger struct {
 	encoder *json.Encoder
 	cfg     *Config
 	env     *tracing.VMContext
+	hooks   *tracing.Hooks
 }
 
 // NewJSONLogger creates a new EVM tracer that prints execution steps as JSON objects
@@ -67,12 +68,14 @@ func NewJSONLogger(cfg *Config, writer io.Writer) *tracing.Hooks {
 	if l.cfg == nil {
 		l.cfg = &Config{}
 	}
-	return &tracing.Hooks{
-		OnTxStart: l.OnTxStart,
-		OnExit:    l.OnExit,
-		OnOpcode:  l.OnOpcode,
-		OnFault:   l.OnFault,
+	l.hooks = &tracing.Hooks{
+		OnTxStart:         l.OnTxStart,
+		OnSystemCallStart: l.onSystemCallStart,
+		OnExit:            l.OnEnd,
+		OnOpcode:          l.OnOpcode,
+		OnFault:           l.OnFault,
 	}
+	return l.hooks
 }
 
 // NewJSONLoggerWithCallFrames creates a new EVM tracer that prints execution steps as JSON objects
@@ -82,13 +85,15 @@ func NewJSONLoggerWithCallFrames(cfg *Config, writer io.Writer) *tracing.Hooks {
 	if l.cfg == nil {
 		l.cfg = &Config{}
 	}
-	return &tracing.Hooks{
-		OnTxStart: l.OnTxStart,
-		OnEnter:   l.OnEnter,
-		OnExit:    l.OnExit,
-		OnOpcode:  l.OnOpcode,
-		OnFault:   l.OnFault,
+	l.hooks = &tracing.Hooks{
+		OnTxStart:         l.OnTxStart,
+		OnSystemCallStart: l.onSystemCallStart,
+		OnEnter:           l.OnEnter,
+		OnExit:            l.OnExit,
+		OnOpcode:          l.OnOpcode,
+		OnFault:           l.OnFault,
 	}
+	return l.hooks
 }
 
 func (l *jsonLogger) OnFault(pc uint64, op byte, gas uint64, cost uint64, scope tracing.OpContext, depth int, err error) {
@@ -122,6 +127,16 @@ func (l *jsonLogger) OnOpcode(pc uint64, op byte, gas, cost uint64, scope tracin
 	l.encoder.Encode(log)
 }
 
+func (l *jsonLogger) onSystemCallStart() {
+	// Process no events while in system call.
+	hooks := *l.hooks
+	*l.hooks = tracing.Hooks{
+		OnSystemCallEnd: func() {
+			*l.hooks = hooks
+		},
+	}
+}
+
 // OnEnter is not enabled by default.
 func (l *jsonLogger) OnEnter(depth int, typ byte, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
 	frame := callFrame{
diff --git a/internal/ethapi/api.go b/internal/ethapi/api.go
index d308cead62..8866a5b870 100644
--- a/internal/ethapi/api.go
+++ b/internal/ethapi/api.go
@@ -966,7 +966,7 @@ func (s *BlockChainAPI) GetBlockReceipts(ctx context.Context, blockNrOrHash rpc.
 // of a message call.
 // Note, state and stateDiff can't be specified at the same time. If state is
 // set, message execution will only use the data in the given state. Otherwise
-// if statDiff is set, all diff will be applied first and then execute the call
+// if stateDiff is set, all diff will be applied first and then execute the call
 // message.
 type OverrideAccount struct {
 	Nonce     *hexutil.Uint64              `json:"nonce"`
@@ -1203,7 +1203,7 @@ func DoEstimateGas(ctx context.Context, b Backend, args TransactionArgs, blockNr
 		return 0, err
 	}
 	call := args.ToMessage(header.BaseFee)
-	// Run the gas estimation andwrap any revertals into a custom return
+	// Run the gas estimation and wrap any revertals into a custom return
 	estimate, revert, err := gasestimator.Estimate(ctx, call, opts, gasCap)
 	if err != nil {
 		if len(revert) > 0 {
diff --git a/metrics/sample_test.go b/metrics/sample_test.go
index d3f092523e..0432437c86 100644
--- a/metrics/sample_test.go
+++ b/metrics/sample_test.go
@@ -114,7 +114,7 @@ func TestExpDecaySample(t *testing.T) {
 		}
 		for _, v := range values {
 			if v > int64(tc.updates) || v < 0 {
-				t.Errorf("out of range [0, %d): %v", tc.updates, v)
+				t.Errorf("out of range [0, %d]: %v", tc.updates, v)
 			}
 		}
 	}
@@ -192,7 +192,7 @@ func TestUniformSample(t *testing.T) {
 	}
 	for _, v := range values {
 		if v > 1000 || v < 0 {
-			t.Errorf("out of range [0, 100): %v\n", v)
+			t.Errorf("out of range [0, 1000]: %v\n", v)
 		}
 	}
 }