diff --git a/identifier.go b/identifier.go
index 763f5bb..b496a86 100644
--- a/identifier.go
+++ b/identifier.go
@@ -7,7 +7,6 @@ import (
 	"io"
 	"strings"
 	"sync"
-	"sync/atomic"
 )
 
 // Identifier is a unique id.
@@ -71,19 +70,6 @@ func cryptoRandIdentifierProvider() (output Identifier) {
 	return
 }
 
-func counterIdentifierProvider() (output Identifier) {
-	newCounter := atomic.AddUint64(&identifierCounter, 1)
-	output[15] = byte(newCounter)
-	output[14] = byte(newCounter >> 8)
-	output[13] = byte(newCounter >> 16)
-	output[12] = byte(newCounter >> 24)
-	output[11] = byte(newCounter >> 32)
-	output[10] = byte(newCounter >> 40)
-	output[9] = byte(newCounter >> 48)
-	output[8] = byte(newCounter >> 56)
-	return
-}
-
 const randPoolSize = 16 * 16
 
 var (
@@ -92,7 +78,6 @@ var (
 	identifierRandPoolPos = randPoolSize     // protected with poolMu
 	identifierRandPool    [randPoolSize]byte // protected with poolMu
 	randomSource          = rand.Reader      // random function
-	identifierCounter     uint64
 )
 
 var zero Identifier
diff --git a/identifier_test.go b/identifier_test.go
index b787f83..a2a3c27 100644
--- a/identifier_test.go
+++ b/identifier_test.go
@@ -4,6 +4,7 @@ import (
 	"encoding/hex"
 	"encoding/json"
 	"fmt"
+	"sync/atomic"
 	"testing"
 
 	"github.com/wcharczuk/go-incr/testutil"
@@ -20,6 +21,21 @@ func Test_Identifier(t *testing.T) {
 	testutil.Equal(t, hex.EncodeToString(id[12:]), id.Short())
 }
 
+var identifierCounter uint64
+
+func counterIdentifierProvider() (output Identifier) {
+	newCounter := atomic.AddUint64(&identifierCounter, 1)
+	output[15] = byte(newCounter)
+	output[14] = byte(newCounter >> 8)
+	output[13] = byte(newCounter >> 16)
+	output[12] = byte(newCounter >> 24)
+	output[11] = byte(newCounter >> 32)
+	output[10] = byte(newCounter >> 40)
+	output[9] = byte(newCounter >> 48)
+	output[8] = byte(newCounter >> 56)
+	return
+}
+
 func Test_SetIdentifierProvider(t *testing.T) {
 	t.Cleanup(func() {
 		SetIdentifierProvider(cryptoRandIdentifierProvider)