diff --git a/client/interop_test.go b/client/interop_test.go
index 9f28f67f..86ab8c3f 100644
--- a/client/interop_test.go
+++ b/client/interop_test.go
@@ -12,10 +12,10 @@ import (
 	"path/filepath"
 	"strings"
 
-	"github.com/agl/ed25519"
 	"github.com/flynn/go-tuf"
 	"github.com/flynn/go-tuf/data"
 	"github.com/flynn/go-tuf/util"
+	"golang.org/x/crypto/ed25519"
 	. "gopkg.in/check.v1"
 )
 
diff --git a/keys/db.go b/keys/db.go
index c932b0d7..13964dd0 100644
--- a/keys/db.go
+++ b/keys/db.go
@@ -4,8 +4,8 @@ import (
 	"crypto/rand"
 	"errors"
 
-	"github.com/agl/ed25519"
 	"github.com/flynn/go-tuf/data"
+	"golang.org/x/crypto/ed25519"
 )
 
 var (
diff --git a/repo_test.go b/repo_test.go
index 1c656276..9ddc4e93 100644
--- a/repo_test.go
+++ b/repo_test.go
@@ -10,12 +10,12 @@ import (
 	"testing"
 	"time"
 
-	"github.com/agl/ed25519"
 	"github.com/flynn/go-tuf/data"
 	"github.com/flynn/go-tuf/encrypted"
 	"github.com/flynn/go-tuf/keys"
 	"github.com/flynn/go-tuf/signed"
 	"github.com/flynn/go-tuf/util"
+	"golang.org/x/crypto/ed25519"
 	. "gopkg.in/check.v1"
 )
 
diff --git a/signed/verifiers.go b/signed/verifiers.go
index 3eeb9cf9..54d9f3bc 100644
--- a/signed/verifiers.go
+++ b/signed/verifiers.go
@@ -1,7 +1,7 @@
 package signed
 
 import (
-	"github.com/agl/ed25519"
+	"golang.org/x/crypto/ed25519"
 )
 
 // Verifier describes the verification interface. Implement this interface
@@ -10,7 +10,7 @@ type Verifier interface {
 	// Verify takes a key, message and signature, all as byte slices,
 	// and determines whether the signature is valid for the given
 	// key and message.
-	Verify(key []byte, msg []byte, sig []byte) error
+	Verify(key, msg, sig []byte) error
 }
 
 // Verifiers is used to map algorithm names to Verifier instances.
@@ -28,16 +28,7 @@ func RegisterVerifier(name string, v Verifier) {
 type Ed25519Verifier struct{}
 
 func (v Ed25519Verifier) Verify(key []byte, msg []byte, sig []byte) error {
-	var sigBytes [ed25519.SignatureSize]byte
-	if len(sig) != len(sigBytes) {
-		return ErrInvalid
-	}
-	copy(sigBytes[:], sig)
-
-	var keyBytes [ed25519.PublicKeySize]byte
-	copy(keyBytes[:], key)
-
-	if !ed25519.Verify(&keyBytes, msg, &sigBytes) {
+	if !ed25519.Verify(key, msg, sig) {
 		return ErrInvalid
 	}
 	return nil
diff --git a/signed/verify.go b/signed/verify.go
index e5a6cb4d..7a52aaed 100644
--- a/signed/verify.go
+++ b/signed/verify.go
@@ -6,10 +6,10 @@ import (
 	"strings"
 	"time"
 
-	"github.com/agl/ed25519"
 	"github.com/flynn/go-tuf/data"
 	"github.com/flynn/go-tuf/keys"
 	"github.com/tent/canonical-json-go"
+	"golang.org/x/crypto/ed25519"
 )
 
 var (
diff --git a/signed/verify_test.go b/signed/verify_test.go
index c8c374dd..47ec59ad 100644
--- a/signed/verify_test.go
+++ b/signed/verify_test.go
@@ -4,9 +4,9 @@ import (
 	"testing"
 	"time"
 
-	"github.com/agl/ed25519"
 	"github.com/flynn/go-tuf/data"
 	"github.com/flynn/go-tuf/keys"
+	"golang.org/x/crypto/ed25519"
 
 	. "gopkg.in/check.v1"
 )