diff --git a/log/logger_test.go b/log/logger_test.go
index a633f5ad7..ff981fd01 100644
--- a/log/logger_test.go
+++ b/log/logger_test.go
@@ -2,6 +2,7 @@ package log
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"io"
 	"math/big"
@@ -77,7 +78,7 @@ func benchmarkLogger(b *testing.B, l Logger) {
 		tt     = time.Now()
 		bigint = big.NewInt(100)
 		nilbig *big.Int
-		err    = fmt.Errorf("Oh nooes it's crap")
+		err    = errors.New("Oh nooes it's crap")
 	)
 	b.ReportAllocs()
 	b.ResetTimer()
@@ -106,7 +107,7 @@ func TestLoggerOutput(t *testing.T) {
 		tt        = time.Time{}
 		bigint    = big.NewInt(100)
 		nilbig    *big.Int
-		err       = fmt.Errorf("Oh nooes it's crap")
+		err       = errors.New("Oh nooes it's crap")
 		smallUint = uint256.NewInt(500_000)
 		bigUint   = &uint256.Int{0xff, 0xff, 0xff, 0xff}
 	)
diff --git a/p2p/server.go b/p2p/server.go
index 8f42765a8..975a3bb91 100644
--- a/p2p/server.go
+++ b/p2p/server.go
@@ -914,13 +914,13 @@ func (srv *Server) checkInboundConn(remoteIP net.IP) error {
 	}
 	// Reject connections that do not match NetRestrict.
 	if srv.NetRestrict != nil && !srv.NetRestrict.Contains(remoteIP) {
-		return fmt.Errorf("not in netrestrict list")
+		return errors.New("not in netrestrict list")
 	}
 	// Reject Internet peers that try too often.
 	now := srv.clock.Now()
 	srv.inboundHistory.expire(now, nil)
 	if !netutil.IsLAN(remoteIP) && srv.inboundHistory.contains(remoteIP.String()) {
-		return fmt.Errorf("too many attempts")
+		return errors.New("too many attempts")
 	}
 	srv.inboundHistory.add(remoteIP.String(), now.Add(inboundThrottleTime))
 	return nil
diff --git a/p2p/transport.go b/p2p/transport.go
index 4f6bb569b..5fc7686fe 100644
--- a/p2p/transport.go
+++ b/p2p/transport.go
@@ -19,6 +19,7 @@ package p2p
 import (
 	"bytes"
 	"crypto/ecdsa"
+	"errors"
 	"fmt"
 	"io"
 	"net"
@@ -157,7 +158,7 @@ func readProtocolHandshake(rw MsgReader) (*protoHandshake, error) {
 		return nil, err
 	}
 	if msg.Size > baseProtocolMaxMsgSize {
-		return nil, fmt.Errorf("message too big")
+		return nil, errors.New("message too big")
 	}
 	if msg.Code == discMsg {
 		// Disconnect before protocol handshake is valid according to the
diff --git a/rpc/types.go b/rpc/types.go
index f88c37c59..d12408178 100644
--- a/rpc/types.go
+++ b/rpc/types.go
@@ -19,6 +19,7 @@ package rpc
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"math"
 	"strings"
@@ -104,7 +105,7 @@ func (bn *BlockNumber) UnmarshalJSON(data []byte) error {
 		return err
 	}
 	if blckNum > math.MaxInt64 {
-		return fmt.Errorf("block number larger than int64")
+		return errors.New("block number larger than int64")
 	}
 	*bn = BlockNumber(blckNum)
 	return nil
@@ -154,7 +155,7 @@ func (bnh *BlockNumberOrHash) UnmarshalJSON(data []byte) error {
 	err := json.Unmarshal(data, &e)
 	if err == nil {
 		if e.BlockNumber != nil && e.BlockHash != nil {
-			return fmt.Errorf("cannot specify both BlockHash and BlockNumber, choose one or the other")
+			return errors.New("cannot specify both BlockHash and BlockNumber, choose one or the other")
 		}
 		bnh.BlockNumber = e.BlockNumber
 		bnh.BlockHash = e.BlockHash
@@ -202,7 +203,7 @@ func (bnh *BlockNumberOrHash) UnmarshalJSON(data []byte) error {
 				return err
 			}
 			if blckNum > math.MaxInt64 {
-				return fmt.Errorf("blocknumber too high")
+				return errors.New("blocknumber too high")
 			}
 			bn := BlockNumber(blckNum)
 			bnh.BlockNumber = &bn