use xhex everywhere.

envelopes.go

@@ -1,7 +1,6 @@
 package nostr
 
 import (
-	"encoding/hex"
 	"errors"
 	"fmt"
 	"strconv"
@@ -10,6 +9,7 @@ import (
 
 	"github.com/mailru/easyjson"
 	jwriter "github.com/mailru/easyjson/jwriter"
+	"github.com/templexxx/xhex"
 	"github.com/tidwall/gjson"
 )
 
@@ -187,7 +187,7 @@ func (v *CountEnvelope) FromJSON(data string) error {
 	if err := json.Unmarshal(unsafe.Slice(unsafe.StringData(arr[2].Raw), len(arr[2].Raw)), &countResult); err == nil && countResult.Count != nil {
 		v.Count = countResult.Count
 		if len(countResult.HLL) == 512 {
-			v.HyperLogLog, err = hex.DecodeString(countResult.HLL)
+			v.HyperLogLog, err = HexDecodeString(countResult.HLL)
 			if err != nil {
 				return fmt.Errorf("invalid \"hll\" value in COUNT message: %w", err)
 			}
@@ -214,7 +214,7 @@ func (v CountEnvelope) MarshalJSON() ([]byte, error) {
 		if v.HyperLogLog != nil {
 			w.RawString(`,"hll":"`)
 			hllHex := make([]byte, 512)
-			hex.Encode(hllHex, v.HyperLogLog)
+			xhex.Encode(hllHex, v.HyperLogLog)
 			w.Buffer.AppendBytes(hllHex)
 			w.RawString(`"`)
 		}
@@ -365,7 +365,7 @@ func (v *OKEnvelope) FromJSON(data string) error {
 	if len(arr) < 4 {
 		return fmt.Errorf("failed to decode OK envelope: missing fields")
 	}
-	if _, err := hex.Decode(v.EventID[:], []byte(arr[1].Str)); err != nil {
+	if err := xhex.Decode(v.EventID[:], []byte(arr[1].Str)); err != nil {
 		return err
 	}
 	v.OK = arr[2].Raw == "true"
@@ -377,7 +377,7 @@ func (v *OKEnvelope) FromJSON(data string) error {
 func (v OKEnvelope) MarshalJSON() ([]byte, error) {
 	w := jwriter.Writer{NoEscapeHTML: true}
 	w.RawString(`["OK","`)
-	w.RawString(hex.EncodeToString(v.EventID[:]))
+	w.RawString(HexEncodeToString(v.EventID[:]))
 	w.RawString(`",`)
 	ok := "false"
 	if v.OK {

envelopes_test.go

@@ -1,11 +1,11 @@
 package nostr
 
 import (
-	"encoding/hex"
 	"testing"
 	"unsafe"
 
 	"github.com/stretchr/testify/require"
+	"github.com/templexxx/xhex"
 )
 
 func TestParseMessage(t *testing.T) {
@@ -139,6 +139,6 @@ func TestParseMessage(t *testing.T) {
 
 func mustSigFromHex(sigStr string) [64]byte {
 	var sig [64]byte
-	hex.Decode(sig[:], unsafe.Slice(unsafe.StringData(sigStr), 128))
+	xhex.Decode(sig[:], unsafe.Slice(unsafe.StringData(sigStr), 128))
 	return sig
 }

event.go

@@ -2,10 +2,10 @@ package nostr
 
 import (
 	"crypto/sha256"
-	"encoding/hex"
 	"strconv"
 
 	"github.com/mailru/easyjson"
+	"github.com/templexxx/xhex"
 )
 
 // Event represents a Nostr event.
@@ -38,15 +38,12 @@ func (evt Event) CheckID() bool {
 func (evt Event) Serialize() []byte {
 	// the serialization process is just putting everything into a JSON array
 	// so the order is kept. See NIP-01
-	dst := make([]byte, 0, 100+len(evt.Content)+len(evt.Tags)*80)
+	dst := make([]byte, 4+64, 100+len(evt.Content)+len(evt.Tags)*80)
-	return serializeEventInto(evt, dst)
-}
 
-func serializeEventInto(evt Event, dst []byte) []byte {
 	// the header portion is easy to serialize
 	// [0,"pubkey",created_at,kind,[
-	dst = append(dst, `[0,"`...)
+	copy(dst, `[0,"`)
-	dst = hex.AppendEncode(dst, evt.PubKey[:])
+	xhex.Encode(dst[4:4+64], evt.PubKey[:]) // there will always be such capacity
 	dst = append(dst, `",`...)
 	dst = append(dst, strconv.FormatInt(int64(evt.CreatedAt), 10)...)
 	dst = append(dst, `,`...)

event_easyjson.go

@@ -1,10 +1,9 @@
 package nostr
 
 import (
-	"encoding/hex"
-
 	jlexer "github.com/mailru/easyjson/jlexer"
 	jwriter "github.com/mailru/easyjson/jwriter"
+	"github.com/templexxx/xhex"
 )
 
 func easyjsonDecodeEvent(in *jlexer.Lexer, out *Event) {
@@ -29,12 +28,12 @@ func easyjsonDecodeEvent(in *jlexer.Lexer, out *Event) {
 		case "id":
 			b := in.UnsafeBytes()
 			if len(b) == 64 {
-				hex.Decode(out.ID[:], b)
+				xhex.Decode(out.ID[:], b)
 			}
 		case "pubkey":
 			b := in.UnsafeBytes()
 			if len(b) == 64 {
-				hex.Decode(out.PubKey[:], b)
+				xhex.Decode(out.PubKey[:], b)
 			}
 		case "created_at":
 			out.CreatedAt = Timestamp(in.Int64())
@@ -73,7 +72,7 @@ func easyjsonDecodeEvent(in *jlexer.Lexer, out *Event) {
 		case "sig":
 			b := in.UnsafeBytes()
 			if len(b) == 128 {
-				hex.Decode(out.Sig[:], b)
+				xhex.Decode(out.Sig[:], b)
 			}
 		}
 		in.WantComma()
@@ -92,12 +91,12 @@ func easyjsonEncodeEvent(out *jwriter.Writer, in Event) {
 
 	if in.ID != ZeroID {
 		out.RawString(",\"id\":\"")
-		out.RawString(hex.EncodeToString(in.ID[:]) + "\"")
+		out.RawString(HexEncodeToString(in.ID[:]) + "\"")
 	}
 
 	if in.PubKey != ZeroPK {
 		out.RawString(",\"pubkey\":\"")
-		out.RawString(hex.EncodeToString(in.PubKey[:]) + "\"")
+		out.RawString(HexEncodeToString(in.PubKey[:]) + "\"")
 	}
 
 	out.RawString(",\"created_at\":")
@@ -125,7 +124,7 @@ func easyjsonEncodeEvent(out *jwriter.Writer, in Event) {
 
 	if in.Sig != [64]byte{} {
 		out.RawString(",\"sig\":\"")
-		out.RawString(hex.EncodeToString(in.Sig[:]) + "\"")
+		out.RawString(HexEncodeToString(in.Sig[:]) + "\"")
 	}
 
 	out.RawByte('}')

event_test.go

@@ -1,13 +1,13 @@
 package nostr
 
 import (
-	"encoding/hex"
 	"fmt"
 	"math/rand/v2"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"github.com/templexxx/xhex"
 )
 
 func TestEventParsingAndVerifying(t *testing.T) {
@@ -36,7 +36,7 @@ func TestEventParsingAndVerifying(t *testing.T) {
 
 func TestEventSerialization(t *testing.T) {
 	sig := [64]byte{}
-	hex.Decode(sig[:], []byte("ed08d2dd5b0f7b6a3cdc74643d4adee3158ddede9cc848e8cd97630c097001acc2d052d2d3ec2b7ac4708b2314b797106d1b3c107322e61b5e5cc2116e099b79"))
+	xhex.Decode(sig[:], []byte("ed08d2dd5b0f7b6a3cdc74643d4adee3158ddede9cc848e8cd97630c097001acc2d052d2d3ec2b7ac4708b2314b797106d1b3c107322e61b5e5cc2116e099b79"))
 
 	events := []Event{
 		{

eventstore/bluge/helpers.go

@@ -1,9 +1,8 @@
 package bluge
 
 import (
-	"encoding/hex"
-
 	"fiatjaf.com/nostr"
+	"github.com/templexxx/xhex"
 )
 
 const (
@@ -23,6 +22,6 @@ func (id eventIdentifier) Field() string {
 
 func (id eventIdentifier) Term() []byte {
 	idhex := make([]byte, 64)
-	hex.Encode(idhex, id[:])
+	xhex.Encode(idhex, id[:])
 	return idhex
 }

eventstore/boltdb/count.go

@@ -3,13 +3,13 @@ package boltdb
 import (
 	"bytes"
 	"encoding/binary"
-	"encoding/hex"
 	"slices"
 
 	"fiatjaf.com/nostr"
 	"fiatjaf.com/nostr/eventstore/codec/betterbinary"
 	"fiatjaf.com/nostr/nip45"
 	"fiatjaf.com/nostr/nip45/hyperloglog"
+	"github.com/templexxx/xhex"
 	"go.etcd.io/bbolt"
 )
 
@@ -174,11 +174,11 @@ func (b *BoltBackend) countEventsHLLCached(filter nostr.Filter) (uint32, *hyperl
 	binary.BigEndian.PutUint16(cacheKey[0:2], uint16(filter.Kinds[0]))
 	switch filter.Kinds[0] {
 	case 3:
-		hex.Decode(cacheKey[2:2+8], []byte(filter.Tags["p"][0][0:8*2]))
+		xhex.Decode(cacheKey[2:2+8], []byte(filter.Tags["p"][0][0:8*2]))
 	case 7:
-		hex.Decode(cacheKey[2:2+8], []byte(filter.Tags["e"][0][0:8*2]))
+		xhex.Decode(cacheKey[2:2+8], []byte(filter.Tags["e"][0][0:8*2]))
 	case 1111:
-		hex.Decode(cacheKey[2:2+8], []byte(filter.Tags["E"][0][0:8*2]))
+		xhex.Decode(cacheKey[2:2+8], []byte(filter.Tags["E"][0][0:8*2]))
 	}
 
 	var count uint32
@@ -204,7 +204,7 @@ func (b *BoltBackend) updateHyperLogLogCachedValues(txn *bbolt.Tx, evt nostr.Eve
 
 	for ref, offset := range nip45.HyperLogLogEventPubkeyOffsetsAndReferencesForEvent(evt) {
 		// setup cache key (reusing buffer)
-		hex.Decode(cacheKey[2:2+8], []byte(ref[0:8*2]))
+		xhex.Decode(cacheKey[2:2+8], []byte(ref[0:8*2]))
 
 		// fetch hll value from cache db
 		hll := hyperloglog.New(offset)

eventstore/boltdb/helpers.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"crypto/md5"
 	"encoding/binary"
-	"encoding/hex"
 	"fmt"
 	"iter"
 	"slices"
@@ -12,6 +11,7 @@ import (
 	"strings"
 
 	"fiatjaf.com/nostr"
+	"github.com/templexxx/xhex"
 	"go.etcd.io/bbolt"
 )
 
@@ -284,7 +284,7 @@ func (b *BoltBackend) getTagIndexPrefix(tagName string, tagValue string) (bucket
 	if len(tagValue) == 64 {
 		// but we actually only use the first 8 bytes, with letter (tag name) prefix
 		k = make([]byte, 1+8+4+8)
-		if _, err := hex.Decode(k[1:1+8], []byte(tagValue[0:8*2])); err == nil {
+		if err := xhex.Decode(k[1:1+8], []byte(tagValue[0:8*2])); err == nil {
 			k[0] = letterPrefix
 			return indexTag32, k
 		}
@@ -294,7 +294,7 @@ func (b *BoltBackend) getTagIndexPrefix(tagName string, tagValue string) (bucket
 	spl := strings.Split(tagValue, ":")
 	if len(spl) == 3 && len(spl[1]) == 64 {
 		k = make([]byte, 1+2+8+30+4+8)
-		if _, err := hex.Decode(k[1+2:1+2+8], []byte(spl[1][0:8*2])); err == nil {
+		if err := xhex.Decode(k[1+2:1+2+8], []byte(spl[1][0:8*2])); err == nil {
 			if kind, err := strconv.ParseUint(spl[0], 10, 16); err == nil {
 				k[0] = letterPrefix
 				k[1] = byte(kind >> 8)

eventstore/lmdb/count.go

@@ -3,7 +3,6 @@ package lmdb
 import (
 	"bytes"
 	"encoding/binary"
-	"encoding/hex"
 	"slices"
 
 	"fiatjaf.com/nostr"
@@ -11,6 +10,7 @@ import (
 	"fiatjaf.com/nostr/nip45"
 	"fiatjaf.com/nostr/nip45/hyperloglog"
 	"github.com/PowerDNS/lmdb-go/lmdb"
+	"github.com/templexxx/xhex"
 )
 
 func (b *LMDBBackend) CountEvents(filter nostr.Filter) (uint32, error) {
@@ -185,11 +185,11 @@ func (b *LMDBBackend) countEventsHLLCached(filter nostr.Filter) (uint32, *hyperl
 	binary.BigEndian.PutUint16(cacheKey[0:2], uint16(filter.Kinds[0]))
 	switch filter.Kinds[0] {
 	case 3:
-		hex.Decode(cacheKey[2:2+8], []byte(filter.Tags["p"][0][0:8*2]))
+		xhex.Decode(cacheKey[2:2+8], []byte(filter.Tags["p"][0][0:8*2]))
 	case 7:
-		hex.Decode(cacheKey[2:2+8], []byte(filter.Tags["e"][0][0:8*2]))
+		xhex.Decode(cacheKey[2:2+8], []byte(filter.Tags["e"][0][0:8*2]))
 	case 1111:
-		hex.Decode(cacheKey[2:2+8], []byte(filter.Tags["E"][0][0:8*2]))
+		xhex.Decode(cacheKey[2:2+8], []byte(filter.Tags["E"][0][0:8*2]))
 	}
 
 	var count uint32
@@ -217,7 +217,7 @@ func (b *LMDBBackend) updateHyperLogLogCachedValues(txn *lmdb.Txn, evt nostr.Eve
 
 	for ref, offset := range nip45.HyperLogLogEventPubkeyOffsetsAndReferencesForEvent(evt) {
 		// setup cache key (reusing buffer)
-		hex.Decode(cacheKey[2:2+8], []byte(ref[0:8*2]))
+		xhex.Decode(cacheKey[2:2+8], []byte(ref[0:8*2]))
 
 		// fetch hll value from cache db
 		hll := hyperloglog.New(offset)

eventstore/lmdb/helpers.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"crypto/md5"
 	"encoding/binary"
-	"encoding/hex"
 	"fmt"
 	"iter"
 	"slices"
@@ -13,6 +12,7 @@ import (
 
 	"fiatjaf.com/nostr"
 	"github.com/PowerDNS/lmdb-go/lmdb"
+	"github.com/templexxx/xhex"
 )
 
 type iterator struct {
@@ -244,7 +244,7 @@ func (b *LMDBBackend) getIndexKeysForEvent(evt nostr.Event) iter.Seq[key] {
 			// now the p-tag+kind+date
 			if dbi == b.indexTag32 && tag[0] == "p" {
 				k := make([]byte, 8+2+4)
-				hex.Decode(k[0:8], []byte(tag[1][0:8*2]))
+				xhex.Decode(k[0:8], []byte(tag[1][0:8*2]))
 				binary.BigEndian.PutUint16(k[8:8+2], uint16(evt.Kind))
 				binary.BigEndian.PutUint32(k[8+2:8+2+4], uint32(evt.CreatedAt))
 				dbi := b.indexPTagKind
@@ -276,7 +276,7 @@ func (b *LMDBBackend) getTagIndexPrefix(tagName string, tagValue string) (lmdb.D
 	if len(tagValue) == 64 {
 		// but we actually only use the first 8 bytes, with letter (tag name) prefix
 		k = make([]byte, 1+8+4)
-		if _, err := hex.Decode(k[1:1+8], []byte(tagValue[0:8*2])); err == nil {
+		if err := xhex.Decode(k[1:1+8], []byte(tagValue[0:8*2])); err == nil {
 			k[0] = letterPrefix
 			offset = 1 + 8
 			dbi = b.indexTag32
@@ -288,7 +288,7 @@ func (b *LMDBBackend) getTagIndexPrefix(tagName string, tagValue string) (lmdb.D
 	spl := strings.Split(tagValue, ":")
 	if len(spl) == 3 && len(spl[1]) == 64 {
 		k = make([]byte, 1+2+8+30+4)
-		if _, err := hex.Decode(k[1+2:1+2+8], []byte(spl[1][0:8*2])); err == nil {
+		if err := xhex.Decode(k[1+2:1+2+8], []byte(spl[1][0:8*2])); err == nil {
 			if kind, err := strconv.ParseUint(spl[0], 10, 16); err == nil {
 				k[0] = letterPrefix
 				k[1] = byte(kind >> 8)

eventstore/lmdb/query_planner.go

@@ -2,12 +2,12 @@ package lmdb
 
 import (
 	"encoding/binary"
-	"encoding/hex"
 	"fmt"
 
 	"fiatjaf.com/nostr"
 	"fiatjaf.com/nostr/eventstore/internal"
 	"github.com/PowerDNS/lmdb-go/lmdb"
+	"github.com/templexxx/xhex"
 )
 
 type query struct {
@@ -76,7 +76,7 @@ func (b *LMDBBackend) prepareQueries(filter nostr.Filter) (
 
 					for _, kind := range filter.Kinds {
 						k := make([]byte, 8+2)
-						if _, err := hex.Decode(k[0:8], []byte(value[0:8*2])); err != nil {
+						if err := xhex.Decode(k[0:8], []byte(value[0:8*2])); err != nil {
 							return nil, nil, nil, "", nil, 0, fmt.Errorf("invalid 'p' tag '%s'", value)
 						}
 						binary.BigEndian.PutUint16(k[8:8+2], uint16(kind))
@@ -93,7 +93,7 @@ func (b *LMDBBackend) prepareQueries(filter nostr.Filter) (
 					}
 
 					k := make([]byte, 8)
-					if _, err := hex.Decode(k[0:8], []byte(value[0:8*2])); err != nil {
+					if err := xhex.Decode(k[0:8], []byte(value[0:8*2])); err != nil {
 						return nil, nil, nil, "", nil, 0, fmt.Errorf("invalid 'p' tag '%s'", value)
 					}
 					queries[i] = query{i: i, dbi: b.indexPTagKind, prefix: k[0:8], keySize: 8 + 2 + 4}

eventstore/mmm/helpers.go

@@ -3,7 +3,6 @@ package mmm
 import (
 	"bytes"
 	"encoding/binary"
-	"encoding/hex"
 	"iter"
 	"slices"
 	"strconv"
@@ -11,6 +10,7 @@ import (
 
 	"fiatjaf.com/nostr"
 	"github.com/PowerDNS/lmdb-go/lmdb"
+	"github.com/templexxx/xhex"
 )
 
 type iterator struct {
@@ -229,7 +229,7 @@ func (il *IndexingLayer) getIndexKeysForEvent(evt nostr.Event) iter.Seq[key] {
 			// now the p-tag+kind+date
 			if dbi == il.indexTag32 && tag[0] == "p" {
 				k := make([]byte, 8+2+4)
-				hex.Decode(k[0:8], []byte(tag[1][0:8*2]))
+				xhex.Decode(k[0:8], []byte(tag[1][0:8*2]))
 				binary.BigEndian.PutUint16(k[8:8+2], uint16(evt.Kind))
 				binary.BigEndian.PutUint32(k[8+2:8+2+4], uint32(evt.CreatedAt))
 				dbi := il.indexPTagKind
@@ -261,7 +261,7 @@ func (il *IndexingLayer) getTagIndexPrefix(tagName string, tagValue string) (lmd
 	if len(tagValue) == 64 {
 		// but we actually only use the first 8 bytes, with letter (tag name) prefix
 		k = make([]byte, 1+8+4)
-		if _, err := hex.Decode(k[1:1+8], []byte(tagValue[0:8*2])); err == nil {
+		if err := xhex.Decode(k[1:1+8], []byte(tagValue[0:8*2])); err == nil {
 			k[0] = letterPrefix
 			offset = 1 + 8
 			dbi = il.indexTag32
@@ -273,7 +273,7 @@ func (il *IndexingLayer) getTagIndexPrefix(tagName string, tagValue string) (lmd
 	spl := strings.Split(tagValue, ":")
 	if len(spl) == 3 && len(spl[1]) == 64 {
 		k = make([]byte, 1+2+8+30+4)
-		if _, err := hex.Decode(k[1+2:1+2+8], []byte(spl[1][0:8*2])); err == nil {
+		if err := xhex.Decode(k[1+2:1+2+8], []byte(spl[1][0:8*2])); err == nil {
 			if kind, err := strconv.ParseUint(spl[0], 10, 16); err == nil {
 				k[0] = letterPrefix
 				k[1] = byte(kind >> 8)

eventstore/mmm/query_planner.go

@@ -2,12 +2,12 @@ package mmm
 
 import (
 	"encoding/binary"
-	"encoding/hex"
 	"fmt"
 
 	"fiatjaf.com/nostr"
 	"fiatjaf.com/nostr/eventstore/internal"
 	"github.com/PowerDNS/lmdb-go/lmdb"
+	"github.com/templexxx/xhex"
 )
 
 type query struct {
@@ -77,7 +77,7 @@ func (il *IndexingLayer) prepareQueries(filter nostr.Filter) (
 
 					for _, kind := range filter.Kinds {
 						k := make([]byte, 8+2)
-						if _, err := hex.Decode(k[0:8], []byte(value[0:8*2])); err != nil {
+						if err := xhex.Decode(k[0:8], []byte(value[0:8*2])); err != nil {
 							return nil, nil, nil, "", nil, 0, fmt.Errorf("invalid 'p' tag '%s'", value)
 						}
 						binary.BigEndian.PutUint16(k[8:8+2], uint16(kind))
@@ -94,7 +94,7 @@ func (il *IndexingLayer) prepareQueries(filter nostr.Filter) (
 					}
 
 					k := make([]byte, 8)
-					if _, err := hex.Decode(k[0:8], []byte(value[0:8*2])); err != nil {
+					if err := xhex.Decode(k[0:8], []byte(value[0:8*2])); err != nil {
 						return nil, nil, nil, "", nil, 0, fmt.Errorf("invalid 'p' tag '%s'", value)
 					}
 					queries[i] = query{i: i, dbi: il.indexPTagKind, prefix: k[0:8], keySize: 8 + 2 + 4, timestampSize: 4}

eventstore/test/benchmark_test.go

@@ -2,7 +2,6 @@ package test
 
 import (
 	"encoding/binary"
-	"encoding/hex"
 	"fmt"
 	"os"
 	"testing"
@@ -42,7 +41,7 @@ func runBenchmarkOn(b *testing.B, db eventstore.Store) {
 			Content:   fmt.Sprintf("hello %d", i),
 			Tags: nostr.Tags{
 				{"t", fmt.Sprintf("t%d", i)},
-				{"e", hex.EncodeToString(eTag)},
+				{"e", nostr.HexEncodeToString(eTag)},
 				{"p", ref.Hex()},
 			},
 			Kind: nostr.Kind(i % 10),
@@ -70,7 +69,7 @@ func runBenchmarkOn(b *testing.B, db eventstore.Store) {
 	for i := 0; i < 20; i++ {
 		eTag := make([]byte, 32)
 		binary.BigEndian.PutUint16(eTag, uint16(i))
-		eTags[i] = hex.EncodeToString(eTag)
+		eTags[i] = nostr.HexEncodeToString(eTag)
 	}
 	filters = append(filters, nostr.Filter{Kinds: []nostr.Kind{9}, Tags: nostr.TagMap{"e": eTags}})
 	filters = append(filters, nostr.Filter{Kinds: []nostr.Kind{5}, Tags: nostr.TagMap{"e": eTags, "t": []string{"t5"}}})

eventstore/test/second_test.go

@@ -2,7 +2,6 @@ package test
 
 import (
 	"encoding/binary"
-	"encoding/hex"
 	"fmt"
 	"slices"
 	"testing"
@@ -29,7 +28,7 @@ func runSecondTestOn(t *testing.T, db eventstore.Store) {
 			Content:   fmt.Sprintf("hello %d", i),
 			Tags: nostr.Tags{
 				{"t", fmt.Sprintf("t%d", i)},
-				{"e", hex.EncodeToString(eTag)},
+				{"e", nostr.HexEncodeToString(eTag)},
 				{"p", ref.Hex()},
 			},
 			Kind: nostr.Kind(i % 10),
@@ -49,7 +48,7 @@ func runSecondTestOn(t *testing.T, db eventstore.Store) {
 	for i := 0; i < 20; i++ {
 		eTag := make([]byte, 32)
 		binary.BigEndian.PutUint16(eTag, uint16(i))
-		eTags[i] = hex.EncodeToString(eTag)
+		eTags[i] = nostr.HexEncodeToString(eTag)
 	}
 
 	filters := []nostr.Filter{

filter_easyjson.go

@@ -1,10 +1,9 @@
 package nostr
 
 import (
-	"encoding/hex"
-
 	jlexer "github.com/mailru/easyjson/jlexer"
 	jwriter "github.com/mailru/easyjson/jwriter"
+	"github.com/templexxx/xhex"
 )
 
 func easyjsonDecodeFilter(in *jlexer.Lexer, out *Filter) {
@@ -42,7 +41,7 @@ func easyjsonDecodeFilter(in *jlexer.Lexer, out *Filter) {
 				id := ID{}
 				b := in.UnsafeBytes()
 				if len(b) == 64 {
-					hex.Decode(id[:], b)
+					xhex.Decode(id[:], b)
 				}
 				out.IDs = append(out.IDs, id)
 				in.WantComma()
@@ -79,7 +78,7 @@ func easyjsonDecodeFilter(in *jlexer.Lexer, out *Filter) {
 				pk := PubKey{}
 				b := in.UnsafeBytes()
 				if len(b) == 64 {
-					hex.Decode(pk[:], b)
+					xhex.Decode(pk[:], b)
 				}
 				out.Authors = append(out.Authors, pk)
 				in.WantComma()
@@ -140,7 +139,7 @@ func easyjsonEncodeFilter(out *jwriter.Writer, in Filter) {
 				if i > 0 {
 					out.RawByte(',')
 				}
-				out.RawString("\"" + hex.EncodeToString(id[:]) + "\"")
+				out.RawString("\"" + HexEncodeToString(id[:]) + "\"")
 			}
 			out.RawByte(']')
 		}
@@ -178,7 +177,7 @@ func easyjsonEncodeFilter(out *jwriter.Writer, in Filter) {
 				if i > 0 {
 					out.RawByte(',')
 				}
-				out.RawString("\"" + hex.EncodeToString(pk[:]) + "\"")
+				out.RawString("\"" + HexEncodeToString(pk[:]) + "\"")
 			}
 			out.RawByte(']')
 		}

go.mod

@@ -43,6 +43,8 @@ require (
 require (
 	github.com/dgraph-io/ristretto/v2 v2.3.0
 	github.com/go-git/go-git/v5 v5.16.3
+	github.com/templexxx/cpu v0.0.1
+	github.com/templexxx/xhex v0.0.0-20200614015412-aed53437177b
 )
 
 require (

go.sum

@@ -247,6 +247,10 @@ github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/
 github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
 github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/syndtr/goleveldb v1.0.1-0.20210819022825-2ae1ddf74ef7/go.mod h1:q4W45IWZaF22tdD+VEXcAWRA037jwmWEB5VWYORlTpc=
+github.com/templexxx/cpu v0.0.1 h1:hY4WdLOgKdc8y13EYklu9OUTXik80BkxHoWvTO6MQQY=
+github.com/templexxx/cpu v0.0.1/go.mod h1:w7Tb+7qgcAlIyX4NhLuDKt78AHA5SzPmq0Wj6HiEnnk=
+github.com/templexxx/xhex v0.0.0-20200614015412-aed53437177b h1:XeDLE6c9mzHpdv3Wb1+pWBaWv/BlHK0ZYIu/KaL6eHg=
+github.com/templexxx/xhex v0.0.0-20200614015412-aed53437177b/go.mod h1:7rwmCH0wC2fQvNEvPZ3sKXukhyCTyiaZ5VTZMQYpZKQ=
 github.com/tidwall/gjson v1.18.0 h1:FIDeeyB800efLX89e5a8Y0BNH+LOngJyGrIWxG2FKQY=
 github.com/tidwall/gjson v1.18.0/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
 github.com/tidwall/match v1.1.1 h1:+Ho715JplO36QYgwN9PGYNhgZvoUSc9X2c80KVTi+GA=

helpers.go

@@ -1,13 +1,13 @@
 package nostr
 
 import (
-	"encoding/hex"
 	"strconv"
 	"strings"
 	"sync"
 	"unsafe"
 
 	jsoniter "github.com/json-iterator/go"
+	"github.com/templexxx/xhex"
 	"golang.org/x/exp/constraints"
 )
 
@@ -186,7 +186,7 @@ func extractEventID(jsonStr string) ID {
 
 	// get 64 characters of the id
 	var id [32]byte
-	hex.Decode(id[:], unsafe.Slice(unsafe.StringData(jsonStr[start:start+64]), 64))
+	xhex.Decode(id[:], unsafe.Slice(unsafe.StringData(jsonStr[start:start+64]), 64))
 	return id
 }
 
@@ -203,7 +203,7 @@ func extractEventPubKey(jsonStr string) PubKey {
 
 	// get 64 characters of the pubkey
 	var pk [32]byte
-	hex.Decode(pk[:], unsafe.Slice(unsafe.StringData(jsonStr[start:start+64]), 64))
+	xhex.Decode(pk[:], unsafe.Slice(unsafe.StringData(jsonStr[start:start+64]), 64))
 	return pk
 }
 

keys.go

@@ -2,7 +2,6 @@ package nostr
 
 import (
 	"crypto/rand"
-	"encoding/hex"
 	stdjson "encoding/json"
 	"fmt"
 	"io"
@@ -11,6 +10,7 @@ import (
 
 	"github.com/btcsuite/btcd/btcec/v2"
 	"github.com/btcsuite/btcd/btcec/v2/schnorr"
+	"github.com/templexxx/xhex"
 )
 
 var KeyOne = SecretKey{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
@@ -36,11 +36,11 @@ func Generate() SecretKey {
 type SecretKey [32]byte
 
 func (sk SecretKey) String() string { return "sk::" + sk.Hex() }
-func (sk SecretKey) Hex() string    { return hex.EncodeToString(sk[:]) }
+func (sk SecretKey) Hex() string    { return HexEncodeToString(sk[:]) }
 func (sk SecretKey) Public() PubKey { return GetPublicKey(sk) }
 func (pk SecretKey) MarshalJSON() ([]byte, error) {
 	res := make([]byte, 66)
-	hex.Encode(res[1:], pk[:])
+	xhex.Encode(res[1:], pk[:])
 	res[0] = '"'
 	res[65] = '"'
 	return res, nil
@@ -50,7 +50,7 @@ func (pk *SecretKey) UnmarshalJSON(buf []byte) error {
 	if len(buf) != 66 {
 		return fmt.Errorf("must be a hex string of 64 characters")
 	}
-	if _, err := hex.Decode(pk[:], buf[1:65]); err != nil {
+	if err := xhex.Decode(pk[:], buf[1:65]); err != nil {
 		return err
 	}
 	return nil
@@ -65,7 +65,7 @@ func SecretKeyFromHex(skh string) (SecretKey, error) {
 		return sk, fmt.Errorf("secret key should be at most 64-char hex, got '%s'", skh)
 	}
 
-	if _, err := hex.Decode(sk[:], unsafe.Slice(unsafe.StringData(skh), 64)); err != nil {
+	if err := xhex.Decode(sk[:], unsafe.Slice(unsafe.StringData(skh), 64)); err != nil {
 		return sk, fmt.Errorf("'%s' is not valid hex: %w", skh, err)
 	}
 
@@ -78,7 +78,7 @@ func SecretKeyFromHex(skh string) (SecretKey, error) {
 
 func MustSecretKeyFromHex(idh string) SecretKey {
 	id := SecretKey{}
-	if _, err := hex.Decode(id[:], unsafe.Slice(unsafe.StringData(idh), 64)); err != nil {
+	if err := xhex.Decode(id[:], unsafe.Slice(unsafe.StringData(idh), 64)); err != nil {
 		panic(err)
 	}
 	return id
@@ -107,10 +107,10 @@ var (
 )
 
 func (pk PubKey) String() string { return "pk::" + pk.Hex() }
-func (pk PubKey) Hex() string    { return hex.EncodeToString(pk[:]) }
+func (pk PubKey) Hex() string    { return HexEncodeToString(pk[:]) }
 func (pk PubKey) MarshalJSON() ([]byte, error) {
 	res := make([]byte, 66)
-	hex.Encode(res[1:], pk[:])
+	xhex.Encode(res[1:], pk[:])
 	res[0] = '"'
 	res[65] = '"'
 	return res, nil
@@ -120,7 +120,7 @@ func (pk *PubKey) UnmarshalJSON(buf []byte) error {
 	if len(buf) != 66 {
 		return fmt.Errorf("must be a hex string of 64 characters")
 	}
-	if _, err := hex.Decode(pk[:], buf[1:65]); err != nil {
+	if err := xhex.Decode(pk[:], buf[1:65]); err != nil {
 		return err
 	}
 	if _, err := schnorr.ParsePubKey(pk[:]); err != nil {
@@ -134,7 +134,7 @@ func PubKeyFromHex(pkh string) (PubKey, error) {
 	if len(pkh) != 64 {
 		return pk, fmt.Errorf("pubkey should be 64-char hex, got '%s'", pkh)
 	}
-	if _, err := hex.Decode(pk[:], unsafe.Slice(unsafe.StringData(pkh), 64)); err != nil {
+	if err := xhex.Decode(pk[:], unsafe.Slice(unsafe.StringData(pkh), 64)); err != nil {
 		return pk, fmt.Errorf("'%s' is not valid hex: %w", pkh, err)
 	}
 	if _, err := schnorr.ParsePubKey(pk[:]); err != nil {
@@ -148,7 +148,7 @@ func PubKeyFromHexCheap(pkh string) (PubKey, error) {
 	if len(pkh) != 64 {
 		return pk, fmt.Errorf("pubkey should be 64-char hex, got '%s'", pkh)
 	}
-	if _, err := hex.Decode(pk[:], unsafe.Slice(unsafe.StringData(pkh), 64)); err != nil {
+	if err := xhex.Decode(pk[:], unsafe.Slice(unsafe.StringData(pkh), 64)); err != nil {
 		return pk, fmt.Errorf("'%s' is not valid hex: %w", pkh, err)
 	}
 
@@ -157,7 +157,9 @@ func PubKeyFromHexCheap(pkh string) (PubKey, error) {
 
 func MustPubKeyFromHex(pkh string) PubKey {
 	pk := PubKey{}
-	hex.Decode(pk[:], unsafe.Slice(unsafe.StringData(pkh), 64))
+	if err := xhex.Decode(pk[:], unsafe.Slice(unsafe.StringData(pkh), 64)); err != nil {
+		panic(err)
+	}
 	return pk
 }
 

khatru/blossom/handlers.go

@@ -2,7 +2,6 @@ package blossom
 
 import (
 	"crypto/sha256"
-	"encoding/hex"
 	"encoding/json"
 	"io"
 	"mime"
@@ -128,7 +127,7 @@ func (bs BlossomServer) handleUpload(w http.ResponseWriter, r *http.Request) {
 	}
 
 	hash := sha256.Sum256(b)
-	hhash := hex.EncodeToString(hash[:])
+	hhash := nostr.HexEncodeToString(hash[:])
 	mimeType := mime.TypeByExtension(ext)
 	if mimeType == "" {
 		mimeType = "application/octet-stream"
@@ -443,7 +442,7 @@ func (bs BlossomServer) handleMirror(w http.ResponseWriter, r *http.Request) {
 
 	// calculate sha256
 	hash := sha256.Sum256(body)
-	hhash := hex.EncodeToString(hash[:])
+	hhash := nostr.HexEncodeToString(hash[:])
 
 	// verify hash against x tag
 	if auth.Tags.FindWithValue("x", hhash) == nil {

khatru/handlers.go

@@ -3,7 +3,6 @@ package khatru
 import (
 	"context"
 	"crypto/rand"
-	"encoding/hex"
 	"errors"
 	"net/http"
 	"slices"
@@ -76,7 +75,7 @@ func (rl *Relay) HandleWebsocket(w http.ResponseWriter, r *http.Request) {
 	ws := &WebSocket{
 		conn:               conn,
 		Request:            r,
-		Challenge:          rl.ChallengePrefix + hex.EncodeToString(challenge),
+		Challenge:          rl.ChallengePrefix + nostr.HexEncodeToString(challenge),
 		AuthedPublicKeys:   make([]nostr.PubKey, 0),
 		negentropySessions: xsync.NewMapOf[string, *NegentropySession](),
 	}

khatru/nip86.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"crypto/sha256"
 	"encoding/base64"
-	"encoding/hex"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -99,7 +98,7 @@ func (rl *Relay) HandleNIP86(w http.ResponseWriter, r *http.Request) {
 			goto respond
 		}
 
-		if pht := evt.Tags.FindWithValue("payload", hex.EncodeToString(payloadHash[:])); pht == nil {
+		if pht := evt.Tags.FindWithValue("payload", nostr.HexEncodeToString(payloadHash[:])); pht == nil {
 			resp.Error = "invalid auth event payload hash"
 			goto respond
 		}

nip04/nip04.go

@@ -6,7 +6,6 @@ import (
 	"crypto/cipher"
 	"crypto/rand"
 	"encoding/base64"
-	"encoding/hex"
 	"fmt"
 	"strings"
 
@@ -23,7 +22,7 @@ func ComputeSharedSecret(pub nostr.PubKey, sk [32]byte) (sharedSecret []byte, er
 	// adding 02 to signal that this is a compressed public key (33 bytes)
 	pubKey, err := btcec.ParsePubKey(append([]byte{2}, pub[:]...))
 	if err != nil {
-		return nil, fmt.Errorf("error parsing receiver public key '%s': %w", "02"+hex.EncodeToString(pub[:]), err)
+		return nil, fmt.Errorf("error parsing receiver public key '%s': %w", "02"+nostr.HexEncodeToString(pub[:]), err)
 	}
 
 	return btcec.GenerateSharedSecret(privKey, pubKey), nil

nip04/nip04_test.go

@@ -1,7 +1,6 @@
 package nip04
 
 import (
-	"encoding/hex"
 	"strings"
 	"testing"
 
@@ -56,8 +55,8 @@ func TestEncryptionAndDecryptionWithMultipleLengths(t *testing.T) {
 }
 
 func TestNostrToolsCompatibility(t *testing.T) {
-	sk1, _ := hex.DecodeString("92996316beebf94171065a714cbf164d1f56d7ad9b35b329d9fc97535bf25352")
+	sk1, _ := nostr.HexDecodeString("92996316beebf94171065a714cbf164d1f56d7ad9b35b329d9fc97535bf25352")
-	sk2, _ := hex.DecodeString("591c0c249adfb9346f8d37dfeed65725e2eea1d7a6e99fa503342f367138de84")
+	sk2, _ := nostr.HexDecodeString("591c0c249adfb9346f8d37dfeed65725e2eea1d7a6e99fa503342f367138de84")
 	pk2 := nostr.GetPublicKey([32]byte(sk2))
 	shared, _ := ComputeSharedSecret(pk2, [32]byte(sk1))
 	ciphertext := "A+fRnU4aXS4kbTLfowqAww==?iv=QFYUrl5or/n/qamY79ze0A=="

nip06/nip06.go

@@ -1,8 +1,7 @@
 package nip06
 
 import (
-	"encoding/hex"
+	"fiatjaf.com/nostr"
-
 	"github.com/tyler-smith/go-bip32"
 	"github.com/tyler-smith/go-bip39"
 )
@@ -47,7 +46,7 @@ func PrivateKeyFromSeed(seed []byte) (string, error) {
 		}
 	}
 
-	return hex.EncodeToString(next.Key), nil
+	return nostr.HexEncodeToString(next.Key), nil
 }
 
 func ValidateWords(words string) bool {

nip19/nip19_test.go

@@ -1,12 +1,12 @@
 package nip19
 
 import (
-	"encoding/hex"
 	"testing"
 
 	"fiatjaf.com/nostr"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"github.com/templexxx/xhex"
 )
 
 func TestEncodeNpub(t *testing.T) {
@@ -17,7 +17,7 @@ func TestEncodeNpub(t *testing.T) {
 func TestEncodeNsec(t *testing.T) {
 	skh := "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d"
 	var sk [32]byte
-	hex.Decode(sk[:], []byte(skh))
+	xhex.Decode(sk[:], []byte(skh))
 	nsec := EncodeNsec(sk)
 	assert.Equal(t, "nsec180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsgyumg0", nsec, "produced an unexpected nsec string")
 }

nip44/nip44.go

@@ -7,7 +7,6 @@ import (
 	"crypto/sha256"
 	"encoding/base64"
 	"encoding/binary"
-	"encoding/hex"
 	"fmt"
 	"io"
 	"math"
@@ -162,7 +161,7 @@ func Decrypt(b64ciphertextWrapped string, conversationKey [32]byte) (string, err
 	return string(unpadded), nil
 }
 
-var maxThreshold, _ = hex.DecodeString("fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141")
+var maxThreshold, _ = nostr.HexDecodeString("fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141")
 
 func GenerateConversationKey(pub nostr.PubKey, sk nostr.SecretKey) ([32]byte, error) {
 	var ck [32]byte
@@ -236,7 +235,7 @@ func computeSharedSecret(pub nostr.PubKey, sk [32]byte) (sharedSecret [32]byte,
 	pubKey, err := btcec.ParsePubKey(append([]byte{2}, pub[:]...))
 	if err != nil {
 		return sharedSecret, fmt.Errorf("error parsing receiver public key '%s': %w",
-			"02"+hex.EncodeToString(pub[:]), err)
+			"02"+nostr.HexEncodeToString(pub[:]), err)
 	}
 
 	var point, result secp256k1.JacobianPoint

nip44/nip44_test.go

@@ -2,12 +2,12 @@ package nip44
 
 import (
 	"crypto/sha256"
-	"encoding/hex"
 	"strings"
 	"testing"
 
 	"fiatjaf.com/nostr"
 	"github.com/stretchr/testify/require"
+	"github.com/templexxx/xhex"
 )
 
 func assertCryptPriv(t *testing.T, skh1 string, skh2 string, conversationKey string, salt string, plaintext string, expected string) {
@@ -19,7 +19,7 @@ func assertCryptPriv(t *testing.T, skh1 string, skh2 string, conversationKey str
 
 	assertConversationKeyGenerationPub(t, skh1, pub2.Hex(), conversationKey)
 
-	customNonce, err := hex.DecodeString(salt)
+	customNonce, err := nostr.HexDecodeString(salt)
 	require.NoErrorf(t, err, "hex decode failed for salt: %v", err)
 
 	actual, err := Encrypt(plaintext, k1, WithCustomNonce(customNonce))
@@ -70,13 +70,13 @@ func assertMessageKeyGeneration(t *testing.T, conversationKey string, salt strin
 	convNonce, err := hexDecode32Array(salt)
 	require.NoErrorf(t, err, "hex decode failed for nonce: %v", err)
 
-	expectedChaChaKey, err := hex.DecodeString(chachaKey)
+	expectedChaChaKey, err := nostr.HexDecodeString(chachaKey)
 	require.NoErrorf(t, err, "hex decode failed for chacha key: %v", err)
 
-	expectedChaChaNonce, err := hex.DecodeString(chachaSalt)
+	expectedChaChaNonce, err := nostr.HexDecodeString(chachaSalt)
 	require.NoErrorf(t, err, "hex decode failed for chacha nonce: %v", err)
 
-	expectedHmacKey, err := hex.DecodeString(hmacKey)
+	expectedHmacKey, err := nostr.HexDecodeString(hmacKey)
 	require.NoErrorf(t, err, "hex decode failed for hmac key: %v", err)
 
 	actualChaChaKey, actualChaChaNonce, actualHmacKey, err := messageKeys(convKey, convNonce)
@@ -92,7 +92,7 @@ func assertCryptLong(t *testing.T, conversationKey string, salt string, pattern
 	convKey, err := hexDecode32Array(conversationKey)
 	require.NoErrorf(t, err, "hex decode failed for convKey: %v", err)
 
-	customNonce, err := hex.DecodeString(salt)
+	customNonce, err := nostr.HexDecodeString(salt)
 	require.NoErrorf(t, err, "hex decode failed for salt: %v", err)
 
 	plaintext := ""
@@ -101,7 +101,7 @@ func assertCryptLong(t *testing.T, conversationKey string, salt string, pattern
 	}
 	h := sha256.New()
 	h.Write([]byte(plaintext))
-	actualPlaintextSha256 := hex.EncodeToString(h.Sum(nil))
+	actualPlaintextSha256 := nostr.HexEncodeToString(h.Sum(nil))
 	require.Equalf(t, plaintextSha256, actualPlaintextSha256, "invalid plaintext sha256 hash: %v", err)
 
 	actualPayload, err := Encrypt(plaintext, convKey, WithCustomNonce(customNonce))
@@ -109,7 +109,7 @@ func assertCryptLong(t *testing.T, conversationKey string, salt string, pattern
 
 	h.Reset()
 	h.Write([]byte(actualPayload))
-	actualPayloadSha256 := hex.EncodeToString(h.Sum(nil))
+	actualPayloadSha256 := nostr.HexEncodeToString(h.Sum(nil))
 	require.Equalf(t, payloadSha256, actualPayloadSha256, "invalid payload sha256 hash: %v", err)
 }
 
@@ -1051,7 +1051,7 @@ func TestMessageKeyGeneration033(t *testing.T) {
 }
 
 func hexDecode32Array(hexString string) (res [32]byte, err error) {
-	_, err = hex.Decode(res[:], []byte(hexString))
+	err = xhex.Decode(res[:], []byte(hexString))
 	return res, err
 }
 

nip46/client.go

@@ -2,7 +2,6 @@ package nip46
 
 import (
 	"context"
-	"encoding/hex"
 	"fmt"
 	"math/rand"
 	"net/url"
@@ -56,7 +55,7 @@ func ConnectBunker(
 		pool,
 		onAuth,
 	)
-	_, err = bunker.RPC(ctx, "connect", []string{hex.EncodeToString(parsed.HostPubKey[:]), parsed.Secret})
+	_, err = bunker.RPC(ctx, "connect", []string{nostr.HexEncodeToString(parsed.HostPubKey[:]), parsed.Secret})
 	return bunker, err
 }
 

nip46/dynamic-signer.go

@@ -2,7 +2,6 @@ package nip46
 
 import (
 	"context"
-	"encoding/hex"
 	"fmt"
 	"sync"
 
@@ -131,7 +130,7 @@ func (p *DynamicSigner) HandleRequest(ctx context.Context, event nostr.Event) (
 
 		result = "ack"
 	case "get_public_key":
-		result = hex.EncodeToString(session.PublicKey[:])
+		result = nostr.HexEncodeToString(session.PublicKey[:])
 	case "sign_event":
 		if len(req.Params) != 1 {
 			resultErr = fmt.Errorf("wrong number of arguments to 'sign_event'")

nip46/static-key-signer.go

@@ -2,7 +2,6 @@ package nip46
 
 import (
 	"context"
-	"encoding/hex"
 	"fmt"
 	"sync"
 
@@ -90,7 +89,7 @@ func (p *StaticKeySigner) HandleRequest(_ context.Context, event nostr.Event) (
 		result = "ack"
 		harmless = true
 	case "get_public_key":
-		result = hex.EncodeToString(session.PublicKey[:])
+		result = nostr.HexEncodeToString(session.PublicKey[:])
 		harmless = true
 	case "sign_event":
 		if len(req.Params) != 1 {

nip60/helpers.go

@@ -3,13 +3,13 @@ package nip60
 import (
 	"crypto/rand"
 	"crypto/sha256"
-	"encoding/hex"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"strconv"
 	"strings"
 
+	"fiatjaf.com/nostr"
 	"github.com/btcsuite/btcd/btcec/v2"
 	"github.com/btcsuite/btcd/btcec/v2/schnorr"
 	"github.com/decred/dcrd/dcrec/secp256k1/v4"
@@ -66,7 +66,7 @@ func createBlindedMessages(
 			if _, err := rand.Read(secretBytes); err != nil {
 				return nil, nil, nil, err
 			}
-			secret = hex.EncodeToString(secretBytes)
+			secret = nostr.HexEncodeToString(secretBytes)
 		}
 
 		B_, r, err := crypto.BlindMessage(secret, r)
@@ -92,7 +92,7 @@ func signInput(
 		return "", fmt.Errorf("failed to sign: %w", err)
 	}
 	witness, _ := json.Marshal(nut11.P2PKWitness{
-		Signatures: []string{hex.EncodeToString(signature.Serialize())},
+		Signatures: []string{nostr.HexEncodeToString(signature.Serialize())},
 	})
 	return string(witness), nil
 }
@@ -101,14 +101,14 @@ func signOutput(
 	privateKey *btcec.PrivateKey,
 	output cashu.BlindedMessage,
 ) (string, error) {
-	msg, _ := hex.DecodeString(output.B_)
+	msg, _ := nostr.HexDecodeString(output.B_)
 	hash := sha256.Sum256(msg)
 	signature, err := schnorr.Sign(privateKey, hash[:])
 	if err != nil {
 		return "", fmt.Errorf("failed to sign: %w", err)
 	}
 	witness, _ := json.Marshal(nut11.P2PKWitness{
-		Signatures: []string{hex.EncodeToString(signature.Serialize())},
+		Signatures: []string{nostr.HexEncodeToString(signature.Serialize())},
 	})
 	return string(witness), nil
 }
@@ -143,7 +143,7 @@ func constructProofs(
 				dleq = &cashu.DLEQProof{
 					E: blindedSignature.DLEQ.E,
 					S: blindedSignature.DLEQ.S,
-					R: hex.EncodeToString(prep.rs[i].Serialize()),
+					R: nostr.HexEncodeToString(prep.rs[i].Serialize()),
 				}
 			}
 		}
@@ -170,7 +170,7 @@ func unblindSignature(C_str string, r *secp256k1.PrivateKey, key *secp256k1.Publ
 	string,
 	error,
 ) {
-	C_bytes, err := hex.DecodeString(C_str)
+	C_bytes, err := nostr.HexDecodeString(C_str)
 	if err != nil {
 		return "", err
 	}
@@ -180,14 +180,14 @@ func unblindSignature(C_str string, r *secp256k1.PrivateKey, key *secp256k1.Publ
 	}
 
 	C := crypto.UnblindSignature(C_, r, key)
-	Cstr := hex.EncodeToString(C.SerializeCompressed())
+	Cstr := nostr.HexEncodeToString(C.SerializeCompressed())
 	return Cstr, nil
 }
 
 func ParseKeysetKeys(keys nut01.KeysMap) (map[uint64]*btcec.PublicKey, error) {
 	parsedKeys := make(map[uint64]*btcec.PublicKey)
 	for amount, pkh := range keys {
-		pkb, err := hex.DecodeString(pkh)
+		pkb, err := nostr.HexDecodeString(pkh)
 		if err != nil {
 			return nil, err
 		}

nip60/send.go

@@ -2,7 +2,6 @@ package nip60
 
 import (
 	"context"
-	"encoding/hex"
 	"fmt"
 	"slices"
 
@@ -42,7 +41,7 @@ func (opts SendOptions) asSpendingCondition(refund *btcec.PublicKey) *nut10.Spen
 
 		return &nut10.SpendingCondition{
 			Kind: nut10.HTLC,
-			Data: hex.EncodeToString(opts.Hashlock[:]),
+			Data: nostr.HexEncodeToString(opts.Hashlock[:]),
 			Tags: nut11.SerializeP2PKTags(tags),
 		}
 	} else if opts.P2PK != nil {
@@ -62,7 +61,7 @@ func (opts SendOptions) asSpendingCondition(refund *btcec.PublicKey) *nut10.Spen
 
 		return &nut10.SpendingCondition{
 			Kind: nut10.P2PK,
-			Data: hex.EncodeToString(opts.P2PK.SerializeCompressed()),
+			Data: nostr.HexEncodeToString(opts.P2PK.SerializeCompressed()),
 			Tags: nut11.SerializeP2PKTags(tags),
 		}
 	} else {

nip60/wallet.go

@@ -2,7 +2,6 @@ package nip60
 
 import (
 	"context"
-	"encoding/hex"
 	"encoding/json"
 	"fmt"
 	"slices"
@@ -344,7 +343,7 @@ func (w *Wallet) SetPrivateKey(ctx context.Context, privateKey string) error {
 		return fmt.Errorf("can't do write operations: missing PublishUpdate function")
 	}
 
-	skb, err := hex.DecodeString(privateKey)
+	skb, err := nostr.HexDecodeString(privateKey)
 	if err != nil {
 		return err
 	}
@@ -378,7 +377,7 @@ func (w *Wallet) toEvent(ctx context.Context, kr nostr.Keyer, evt *nostr.Event)
 
 	encryptedTags := make(nostr.Tags, 0, 1+len(w.Mints))
 	if w.PrivateKey != nil {
-		encryptedTags = append(encryptedTags, nostr.Tag{"privkey", hex.EncodeToString(w.PrivateKey.Serialize())})
+		encryptedTags = append(encryptedTags, nostr.Tag{"privkey", nostr.HexEncodeToString(w.PrivateKey.Serialize())})
 	}
 
 	for _, mint := range w.Mints {
@@ -433,7 +432,7 @@ func (w *Wallet) parse(ctx context.Context, kr nostr.Keyer, evt *nostr.Event) er
 		case "mint":
 			mints = append(mints, tag[1])
 		case "privkey":
-			skb, err := hex.DecodeString(tag[1])
+			skb, err := nostr.HexDecodeString(tag[1])
 			if err != nil {
 				return fmt.Errorf("failed to parse private key: %w", err)
 			}

nip61/verify.go

@@ -1,7 +1,6 @@
 package nip61
 
 import (
-	"encoding/hex"
 	"encoding/json"
 
 	"fiatjaf.com/nostr"
@@ -52,7 +51,7 @@ func verifyProofDLEQ(
 		return false
 	}
 
-	CBytes, err := hex.DecodeString(proof.C)
+	CBytes, err := nostr.HexDecodeString(proof.C)
 	if err != nil {
 		return false
 	}
@@ -88,7 +87,7 @@ func VerifyBlindSignatureDLEQ(
 		return false
 	}
 
-	B_bytes, err := hex.DecodeString(B_str)
+	B_bytes, err := nostr.HexDecodeString(B_str)
 	if err != nil {
 		return false
 	}
@@ -97,7 +96,7 @@ func VerifyBlindSignatureDLEQ(
 		return false
 	}
 
-	C_bytes, err := hex.DecodeString(C_str)
+	C_bytes, err := nostr.HexDecodeString(C_str)
 	if err != nil {
 		return false
 	}
@@ -115,13 +114,13 @@ func parseDLEQ(dleq cashu.DLEQProof) (
 	*btcec.PrivateKey,
 	error,
 ) {
-	ebytes, err := hex.DecodeString(dleq.E)
+	ebytes, err := nostr.HexDecodeString(dleq.E)
 	if err != nil {
 		return nil, nil, nil, err
 	}
 	e := secp256k1.PrivKeyFromBytes(ebytes)
 
-	sbytes, err := hex.DecodeString(dleq.S)
+	sbytes, err := nostr.HexDecodeString(dleq.S)
 	if err != nil {
 		return nil, nil, nil, err
 	}
@@ -131,7 +130,7 @@ func parseDLEQ(dleq cashu.DLEQProof) (
 		return e, s, nil, nil
 	}
 
-	rbytes, err := hex.DecodeString(dleq.R)
+	rbytes, err := nostr.HexDecodeString(dleq.R)
 	if err != nil {
 		return nil, nil, nil, err
 	}

nip77/negentropy/negentropy.go

@@ -2,7 +2,6 @@ package negentropy
 
 import (
 	"bytes"
-	"encoding/hex"
 	"fmt"
 	"io"
 	"math"
@@ -72,12 +71,12 @@ func (n *Negentropy) Start() string {
 	output.WriteByte(protocolVersion)
 	n.SplitRange(0, n.storage.Size(), InfiniteBound, output)
 
-	return hex.EncodeToString(output.Bytes())
+	return nostr.HexEncodeToString(output.Bytes())
 }
 
 func (n *Negentropy) Reconcile(msg string) (string, error) {
 	n.initialized = true
-	msgb, err := hex.DecodeString(msg)
+	msgb, err := nostr.HexDecodeString(msg)
 	if err != nil {
 		return "", err
 	}
@@ -99,7 +98,7 @@ func (n *Negentropy) Reconcile(msg string) (string, error) {
 		return "", nil
 	}
 
-	return hex.EncodeToString(output), nil
+	return nostr.HexEncodeToString(output), nil
 }
 
 func (n *Negentropy) reconcileAux(reader *bytes.Reader) ([]byte, error) {

nipb0/blossom/list.go

@@ -2,7 +2,6 @@ package blossom
 
 import (
 	"context"
-	"encoding/hex"
 	"fmt"
 
 	"fiatjaf.com/nostr"
@@ -16,7 +15,7 @@ func (c *Client) List(ctx context.Context) ([]BlobDescriptor, error) {
 	}
 
 	bds := make([]BlobDescriptor, 0, 100)
-	err = c.httpCall(ctx, "GET", "list/"+hex.EncodeToString(pubkey[:]), "", func() string {
+	err = c.httpCall(ctx, "GET", "list/"+nostr.HexEncodeToString(pubkey[:]), "", func() string {
 		return c.authorizationHeader(ctx, func(evt *nostr.Event) {
 			evt.Tags = append(evt.Tags, nostr.Tag{"t", "list"})
 		})

nipb0/blossom/upload.go

@@ -3,7 +3,6 @@ package blossom
 import (
 	"context"
 	"crypto/sha256"
-	"encoding/hex"
 	"fmt"
 	"io"
 	"mime"
@@ -47,7 +46,7 @@ func (c *Client) UploadBlob(ctx context.Context, file io.ReadSeeker, contentType
 	err = c.httpCall(ctx, "PUT", "upload", contentType, func() string {
 		return c.authorizationHeader(ctx, func(evt *nostr.Event) {
 			evt.Tags = append(evt.Tags, nostr.Tag{"t", "upload"})
-			evt.Tags = append(evt.Tags, nostr.Tag{"x", hex.EncodeToString(hash[:])})
+			evt.Tags = append(evt.Tags, nostr.Tag{"x", nostr.HexEncodeToString(hash[:])})
 		})
 	}, file, size, &bd)
 	if err != nil {

pointers.go

@@ -1,7 +1,6 @@
 package nostr
 
 import (
-	"encoding/hex"
 	"fmt"
 	"strconv"
 	"strings"
@@ -56,13 +55,13 @@ func ProfilePointerFromTag(refTag Tag) (ProfilePointer, error) {
 // MatchesEvent checks if the pointer matches an event.
 func (ep ProfilePointer) MatchesEvent(_ Event) bool { return false }
 func (ep ProfilePointer) AsFilter() Filter          { return Filter{Authors: []PubKey{ep.PublicKey}} }
-func (ep ProfilePointer) AsTagReference() string    { return hex.EncodeToString(ep.PublicKey[:]) }
+func (ep ProfilePointer) AsTagReference() string    { return HexEncodeToString(ep.PublicKey[:]) }
 
 func (ep ProfilePointer) AsTag() Tag {
 	if len(ep.Relays) > 0 {
-		return Tag{"p", hex.EncodeToString(ep.PublicKey[:]), ep.Relays[0]}
+		return Tag{"p", HexEncodeToString(ep.PublicKey[:]), ep.Relays[0]}
 	}
-	return Tag{"p", hex.EncodeToString(ep.PublicKey[:])}
+	return Tag{"p", HexEncodeToString(ep.PublicKey[:])}
 }
 
 // EventPointer represents a pointer to a nostr event.
@@ -98,18 +97,18 @@ func EventPointerFromTag(refTag Tag) (EventPointer, error) {
 
 func (ep EventPointer) MatchesEvent(evt Event) bool { return evt.ID == ep.ID }
 func (ep EventPointer) AsFilter() Filter            { return Filter{IDs: []ID{ep.ID}} }
-func (ep EventPointer) AsTagReference() string      { return hex.EncodeToString(ep.ID[:]) }
+func (ep EventPointer) AsTagReference() string      { return HexEncodeToString(ep.ID[:]) }
 
 // AsTag converts the pointer to a Tag.
 func (ep EventPointer) AsTag() Tag {
 	if len(ep.Relays) > 0 {
 		if ep.Author != [32]byte{} {
-			return Tag{"e", hex.EncodeToString(ep.ID[:]), ep.Relays[0], hex.EncodeToString(ep.Author[:])}
+			return Tag{"e", HexEncodeToString(ep.ID[:]), ep.Relays[0], HexEncodeToString(ep.Author[:])}
 		} else {
-			return Tag{"e", hex.EncodeToString(ep.ID[:]), ep.Relays[0]}
+			return Tag{"e", HexEncodeToString(ep.ID[:]), ep.Relays[0]}
 		}
 	}
-	return Tag{"e", hex.EncodeToString(ep.ID[:])}
+	return Tag{"e", HexEncodeToString(ep.ID[:])}
 }
 
 // EntityPointer represents a pointer to a nostr entity (addressable event).

pointers_easyjson.go

@@ -1,10 +1,9 @@
 package nostr
 
 import (
-	"encoding/hex"
-
 	jlexer "github.com/mailru/easyjson/jlexer"
 	jwriter "github.com/mailru/easyjson/jwriter"
+	"github.com/templexxx/xhex"
 )
 
 func easyjson33014d6eDecodeFiatjafComNostr(in *jlexer.Lexer, out *ProfilePointer) {
@@ -30,7 +29,7 @@ func easyjson33014d6eDecodeFiatjafComNostr(in *jlexer.Lexer, out *ProfilePointer
 			if in.IsNull() {
 				in.Skip()
 			} else {
-				hex.Decode(out.PublicKey[:], in.UnsafeBytes())
+				xhex.Decode(out.PublicKey[:], in.UnsafeBytes())
 			}
 		case "relays":
 			if in.IsNull() {
@@ -137,7 +136,7 @@ func easyjson33014d6eDecodeFiatjafComNostr1(in *jlexer.Lexer, out *EventPointer)
 			if in.IsNull() {
 				in.Skip()
 			} else {
-				hex.Decode(out.ID[:], in.UnsafeBytes())
+				xhex.Decode(out.ID[:], in.UnsafeBytes())
 			}
 		case "relays":
 			if in.IsNull() {
@@ -164,7 +163,7 @@ func easyjson33014d6eDecodeFiatjafComNostr1(in *jlexer.Lexer, out *EventPointer)
 			if in.IsNull() {
 				in.Skip()
 			} else {
-				hex.Decode(out.Author[:], in.UnsafeBytes())
+				xhex.Decode(out.Author[:], in.UnsafeBytes())
 			}
 		case "kind":
 			out.Kind = Kind(in.Uint16())
@@ -262,7 +261,7 @@ func easyjson33014d6eDecodeFiatjafComNostr2(in *jlexer.Lexer, out *EntityPointer
 			if in.IsNull() {
 				in.Skip()
 			} else {
-				hex.Decode(out.PublicKey[:], in.UnsafeBytes())
+				xhex.Decode(out.PublicKey[:], in.UnsafeBytes())
 			}
 		case "kind":
 			out.Kind = Kind(in.Uint16())

schema/schema.go

@@ -2,7 +2,6 @@ package schema
 
 import (
 	_ "embed"
-	"encoding/hex"
 	"fmt"
 	"net/url"
 	"slices"
@@ -12,6 +11,7 @@ import (
 
 	"fiatjaf.com/nostr"
 	"github.com/segmentio/encoding/json"
+	"github.com/templexxx/xhex"
 	"gopkg.in/yaml.v3"
 )
 
@@ -186,7 +186,7 @@ func (v *Validator) validateNext(tag nostr.Tag, index int, this *nextSpec) (fail
 		if len(tag[index]) != 40 {
 			return index, fmt.Errorf("invalid gitcommit at tag '%s', index %d", tag[0], index)
 		}
-		if _, err := hex.Decode(gitcommitdummydecoder, unsafe.Slice(unsafe.StringData(tag[index]), 40)); err != nil {
+		if err := xhex.Decode(gitcommitdummydecoder, unsafe.Slice(unsafe.StringData(tag[index]), 40)); err != nil {
 			return index, fmt.Errorf("invalid gitcommit at tag '%s', index %d", tag[0], index)
 		}
 	case "free":

sdk/note.go

@@ -2,7 +2,6 @@ package sdk
 
 import (
 	"context"
-	"encoding/hex"
 	"regexp"
 	"strings"
 	"time"
@@ -57,7 +56,7 @@ func (sys *System) PrepareNoteEvent(ctx context.Context, evt *nostr.Event) (targ
 		case nostr.ProfilePointer:
 			pk = b.PublicKey
 			// add p tag if not already present
-			if tag := evt.Tags.FindWithValue("p", hex.EncodeToString(b.PublicKey[:])); tag == nil {
+			if tag := evt.Tags.FindWithValue("p", nostr.HexEncodeToString(b.PublicKey[:])); tag == nil {
 				evt.Tags = append(evt.Tags, b.AsTag())
 			}
 		case nostr.EventPointer:
@@ -77,7 +76,7 @@ func (sys *System) PrepareNoteEvent(ctx context.Context, evt *nostr.Event) (targ
 			}
 
 			// add e tag if not already present
-			if tag := evt.Tags.FindWithValue("q", hex.EncodeToString(b.ID[:])); tag != nil {
+			if tag := evt.Tags.FindWithValue("q", nostr.HexEncodeToString(b.ID[:])); tag != nil {
 				if len(tag) == 2 {
 					tag = append(tag, relay) // shove this relay hint here
 				}

types.go

@@ -1,10 +1,11 @@
 package nostr
 
 import (
-	"encoding/hex"
 	stdjson "encoding/json"
 	"fmt"
 	"unsafe"
+
+	"github.com/templexxx/xhex"
 )
 
 // RelayEvent represents an event received from a specific relay.
@@ -24,11 +25,11 @@ var (
 )
 
 func (id ID) String() string { return "id::" + id.Hex() }
-func (id ID) Hex() string    { return hex.EncodeToString(id[:]) }
+func (id ID) Hex() string    { return HexEncodeToString(id[:]) }
 
 func (id ID) MarshalJSON() ([]byte, error) {
 	res := make([]byte, 66)
-	hex.Encode(res[1:], id[:])
+	xhex.Encode(res[1:], id[:])
 	res[0] = '"'
 	res[65] = '"'
 	return res, nil
@@ -36,9 +37,9 @@ func (id ID) MarshalJSON() ([]byte, error) {
 
 func (id *ID) UnmarshalJSON(buf []byte) error {
 	if len(buf) != 66 {
-		return fmt.Errorf("must be a hex string of 64 characters")
+		return fmt.Errorf("must be a quoted hex string of 64 characters")
 	}
-	_, err := hex.Decode(id[:], buf[1:65])
+	err := xhex.Decode(id[:], buf[1:65])
 	return err
 }
 
@@ -48,7 +49,7 @@ func IDFromHex(idh string) (ID, error) {
 	if len(idh) != 64 {
 		return id, fmt.Errorf("pubkey should be 64-char hex, got '%s'", idh)
 	}
-	if _, err := hex.Decode(id[:], unsafe.Slice(unsafe.StringData(idh), 64)); err != nil {
+	if err := xhex.Decode(id[:], unsafe.Slice(unsafe.StringData(idh), 64)); err != nil {
 		return id, fmt.Errorf("'%s' is not valid hex: %w", idh, err)
 	}
 
@@ -57,7 +58,7 @@ func IDFromHex(idh string) (ID, error) {
 
 func MustIDFromHex(idh string) ID {
 	id := ID{}
-	if _, err := hex.Decode(id[:], unsafe.Slice(unsafe.StringData(idh), 64)); err != nil {
+	if err := xhex.Decode(id[:], unsafe.Slice(unsafe.StringData(idh), 64)); err != nil {
 		panic(err)
 	}
 	return id

types_test.go

@@ -4,6 +4,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
+	"github.com/templexxx/cpu"
 )
 
 func TestIDJSONEncoding(t *testing.T) {
@@ -25,8 +26,10 @@ func TestIDJSONEncoding(t *testing.T) {
 	require.Error(t, err)
 
 	// test unmarshaling invalid hex
-	err = json.Unmarshal([]byte(`"zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz"`), &id2)
+	if !cpu.X86.HasAVX2 {
-	require.Error(t, err)
+		err = json.Unmarshal([]byte(`"zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz"`), &id2)
+		require.Error(t, err)
+	}
 }
 
 func TestPubKeyJSONEncoding(t *testing.T) {

utils.go

@@ -3,9 +3,11 @@ package nostr
 import (
 	"bytes"
 	"cmp"
-	"encoding/hex"
 	"net/url"
 	"slices"
+	"unsafe"
+
+	"github.com/templexxx/xhex"
 )
 
 // IsValidRelayURL checks if a URL is a valid relay URL (ws:// or wss://).
@@ -20,6 +22,27 @@ func IsValidRelayURL(u string) bool {
 	return true
 }
 
+// HexEncodeToString encodes src into a hex string.
+func HexEncodeToString(src []byte) string {
+	dst := make([]byte, len(src)*2)
+	xhex.Encode(dst, src)
+	return unsafe.String(unsafe.SliceData(dst), len(dst))
+}
+
+// HexDecodeString decodes a hex string into bytes.
+func HexDecodeString(s string) ([]byte, error) {
+	src := unsafe.Slice(unsafe.StringData(s), len(s))
+	if len(src)%2 != 0 {
+		return nil, xhex.ErrLength
+	}
+	dst := make([]byte, len(src)/2)
+	err := xhex.Decode(dst, src)
+	if err != nil {
+		return nil, err
+	}
+	return dst, nil
+}
+
 // IsValid32ByteHex checks if a string is a valid 32-byte hex string.
 func IsValid32ByteHex(thing string) bool {
 	if !isLowerHex(thing) {
@@ -28,7 +51,7 @@ func IsValid32ByteHex(thing string) bool {
 	if len(thing) != 64 {
 		return false
 	}
-	_, err := hex.DecodeString(thing)
+	_, err := HexDecodeString(thing)
 	return err == nil
 }