diff --git a/caddytls/config.go b/caddytls/config.go
index d3468e34..f008d1ea 100644
--- a/caddytls/config.go
+++ b/caddytls/config.go
@@ -23,7 +23,7 @@ import (
 	"net/url"
 	"strings"
 
-	"github.com/codahale/aesnicheck"
+	"github.com/klauspost/cpuid"
 	"github.com/mholt/caddy"
 	"github.com/xenolf/lego/acme"
 )
@@ -505,7 +505,7 @@ var defaultCiphersNonAESNI = []uint16{
 //
 // See https://github.com/mholt/caddy/issues/1674
 func getPreferredDefaultCiphers() []uint16 {
-	if aesnicheck.HasAESNI() {
+	if cpuid.CPU.AesNi() {
 		return defaultCiphers
 	}
 
diff --git a/caddytls/config_test.go b/caddytls/config_test.go
index 0294e031..c69f2d55 100644
--- a/caddytls/config_test.go
+++ b/caddytls/config_test.go
@@ -21,7 +21,7 @@ import (
 	"reflect"
 	"testing"
 
-	"github.com/codahale/aesnicheck"
+	"github.com/klauspost/cpuid"
 )
 
 func TestConvertTLSConfigProtocolVersions(t *testing.T) {
@@ -98,7 +98,7 @@ func TestConvertTLSConfigCipherSuites(t *testing.T) {
 
 func TestGetPreferredDefaultCiphers(t *testing.T) {
 	expectedCiphers := defaultCiphers
-	if !aesnicheck.HasAESNI() {
+	if !cpuid.CPU.AesNi() {
 		expectedCiphers = defaultCiphersNonAESNI
 	}
 
diff --git a/vendor/github.com/codahale/aesnicheck/LICENSE b/vendor/github.com/codahale/aesnicheck/LICENSE
deleted file mode 100644
index f9835c24..00000000
--- a/vendor/github.com/codahale/aesnicheck/LICENSE
+++ /dev/null
@@ -1,21 +0,0 @@
-The MIT License (MIT)
-
-Copyright (c) 2014 Coda Hale
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in
-all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-THE SOFTWARE.
diff --git a/vendor/github.com/codahale/aesnicheck/asm_amd64.s b/vendor/github.com/codahale/aesnicheck/asm_amd64.s
deleted file mode 100644
index d7ee7ee3..00000000
--- a/vendor/github.com/codahale/aesnicheck/asm_amd64.s
+++ /dev/null
@@ -1,9 +0,0 @@
-// func HasAESNI() bool
-TEXT ·HasAESNI(SB),$0
-	XORQ AX, AX
-	INCL AX
-	CPUID
-	SHRQ $25, CX
-	ANDQ $1, CX
-	MOVB CX, ret+0(FP)
-	RET
diff --git a/vendor/github.com/codahale/aesnicheck/check_asm.go b/vendor/github.com/codahale/aesnicheck/check_asm.go
deleted file mode 100644
index 7b4d332c..00000000
--- a/vendor/github.com/codahale/aesnicheck/check_asm.go
+++ /dev/null
@@ -1,6 +0,0 @@
-// +build amd64
-
-package aesnicheck
-
-// HasAESNI returns whether AES-NI is supported by the CPU.
-func HasAESNI() bool
diff --git a/vendor/github.com/codahale/aesnicheck/check_generic.go b/vendor/github.com/codahale/aesnicheck/check_generic.go
deleted file mode 100644
index b8081603..00000000
--- a/vendor/github.com/codahale/aesnicheck/check_generic.go
+++ /dev/null
@@ -1,8 +0,0 @@
-// +build !amd64
-
-package aesnicheck
-
-// HasAESNI returns whether AES-NI is supported by the CPU.
-func HasAESNI() bool {
-	return false
-}
diff --git a/vendor/github.com/codahale/aesnicheck/cmd/aesnicheck/aesnicheck.go b/vendor/github.com/codahale/aesnicheck/cmd/aesnicheck/aesnicheck.go
deleted file mode 100644
index ecfe1ce8..00000000
--- a/vendor/github.com/codahale/aesnicheck/cmd/aesnicheck/aesnicheck.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Command aesnicheck queries the CPU for AES-NI support. If AES-NI is supported,
-// aesnicheck will print "supported" and exit with a status of 0. If AES-NI is
-// not supported, aesnicheck will print "unsupported" and exit with a status of
-// -1.
-package main
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/codahale/aesnicheck"
-)
-
-func main() {
-	if aesnicheck.HasAESNI() {
-		fmt.Println("supported")
-		os.Exit(0)
-	} else {
-		fmt.Println("unsupported")
-		os.Exit(-1)
-	}
-}
diff --git a/vendor/github.com/codahale/aesnicheck/docs.go b/vendor/github.com/codahale/aesnicheck/docs.go
deleted file mode 100644
index 54fa03e6..00000000
--- a/vendor/github.com/codahale/aesnicheck/docs.go
+++ /dev/null
@@ -1,9 +0,0 @@
-// Package aesnicheck provides a simple check to see if crypto/aes is using
-// AES-NI instructions or if the AES transform is being done in software. AES-NI
-// is constant-time, which makes it impervious to cache-level timing attacks. For
-// security-conscious deployments on public cloud infrastructure (Amazon EC2,
-// Google Compute Engine, Microsoft Azure, etc.) this may be critical.
-//
-// See http://eprint.iacr.org/2014/248 for details on cross-VM timing attacks on
-// AES keys.
-package aesnicheck
diff --git a/vendor/manifest b/vendor/manifest
index b8d13653..a2475e60 100644
--- a/vendor/manifest
+++ b/vendor/manifest
@@ -34,14 +34,6 @@
 			"branch": "master",
 			"notests": true
 		},
-		{
-			"importpath": "github.com/codahale/aesnicheck",
-			"repository": "https://github.com/codahale/aesnicheck",
-			"vcs": "git",
-			"revision": "349fcc471aaccc29cd074e1275f1a494323826cd",
-			"branch": "master",
-			"notests": true
-		},
 		{
 			"importpath": "github.com/dustin/go-humanize",
 			"repository": "https://github.com/dustin/go-humanize",