diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 545066e..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,21 +0,0 @@
-sudo: required
-dist: trusty
-language: go
-
-os:
-- linux
-- osx
-
-osx_image: xcode7.2
-
-go:
-- 1.6
-- 1.5
-
-env:
-- ARCH=x86_64
-- ARCH=i686
-
-script:
-- diff -au <(gofmt -d .) <(printf "")
-- go test -race -v ./...
diff --git a/appveyor.yml b/appveyor.yml
deleted file mode 100644
index 77595fe..0000000
--- a/appveyor.yml
+++ /dev/null
@@ -1,32 +0,0 @@
-# version format
-version: "{build}"
-
-# Operating system (build VM template)
-os: Windows Server 2012 R2
-
-# Platform.
-platform: x64
-
-clone_folder: c:\gopath\src\github.com\minio\blake2b-simd
-
-# environment variables
-environment:
-  GOPATH: c:\gopath
-  GO15VENDOREXPERIMENT: 1
-
-# scripts that run after cloning repository
-install:
-  - set PATH=%GOPATH%\bin;c:\go\bin;%PATH%
-  - go version
-  - go env
-
-# to run your custom scripts instead of automatic MSBuild
-build_script:
-  - go test .
-  - go test -race .
-
-# to disable automatic tests
-test: off
-
-# to disable deployment
-deploy: off
diff --git a/blake2b.go b/blake2b.go
index 538466a..b7d5a97 100644
--- a/blake2b.go
+++ b/blake2b.go
@@ -269,14 +269,7 @@ func (d *digest) checkSum() [Size]byte {
 	var out [Size]byte
 	j := 0
 	for _, s := range d.h[:(d.size-1)/8+1] {
-		out[j+0] = byte(s >> 0)
-		out[j+1] = byte(s >> 8)
-		out[j+2] = byte(s >> 16)
-		out[j+3] = byte(s >> 24)
-		out[j+4] = byte(s >> 32)
-		out[j+5] = byte(s >> 40)
-		out[j+6] = byte(s >> 48)
-		out[j+7] = byte(s >> 56)
+		binary.LittleEndian.PutUint64(out[j:j+8], s)
 		j += 8
 	}
 	return out
diff --git a/compressAvx2_amd64.go b/compressAvx2_amd64.go
index ec53599..0b7d484 100644
--- a/compressAvx2_amd64.go
+++ b/compressAvx2_amd64.go
@@ -1,5 +1,5 @@
-//+build !noasm
-//+build !appengine
+//go:build !noasm && !appengine
+// +build !noasm,!appengine
 
 /*
  * Minio Cloud Storage, (C) 2016 Minio, Inc.
diff --git a/compressAvx2_amd64.s b/compressAvx2_amd64.s
index 24df234..8be6ddc 100644
--- a/compressAvx2_amd64.s
+++ b/compressAvx2_amd64.s
@@ -1,4 +1,5 @@
-//+build !noasm !appengine
+//go:build !noasm && !appengine
+// +build !noasm,!appengine
 
 //
 // Minio Cloud Storage, (C) 2016 Minio, Inc.
diff --git a/compressAvx_amd64.go b/compressAvx_amd64.go
index cfa12c0..91901db 100644
--- a/compressAvx_amd64.go
+++ b/compressAvx_amd64.go
@@ -1,5 +1,5 @@
-//+build !noasm
-//+build !appengine
+//go:build !noasm && !appengine
+// +build !noasm,!appengine
 
 /*
  * Minio Cloud Storage, (C) 2016 Minio, Inc.
diff --git a/compressAvx_amd64.s b/compressAvx_amd64.s
index f68e173..5dea5d8 100644
--- a/compressAvx_amd64.s
+++ b/compressAvx_amd64.s
@@ -1,4 +1,5 @@
-//+build !noasm !appengine
+//go:build !noasm && !appengine
+// +build !noasm,!appengine
 
 //
 // Minio Cloud Storage, (C) 2016 Minio, Inc.
diff --git a/compressSse_amd64.go b/compressSse_amd64.go
index d539a7a..4eebf76 100644
--- a/compressSse_amd64.go
+++ b/compressSse_amd64.go
@@ -1,5 +1,5 @@
-//+build !noasm
-//+build !appengine
+//go:build !noasm && !appengine
+// +build !noasm,!appengine
 
 /*
  * Minio Cloud Storage, (C) 2016 Minio, Inc.
diff --git a/compressSse_amd64.s b/compressSse_amd64.s
index 6f31c94..b51b14b 100644
--- a/compressSse_amd64.s
+++ b/compressSse_amd64.s
@@ -1,4 +1,5 @@
-//+build !noasm !appengine
+//go:build !noasm && !appengine
+// +build !noasm,!appengine
 
 //
 // Minio Cloud Storage, (C) 2016 Minio, Inc.
diff --git a/compress_generic.go b/compress_generic.go
index e9e16e8..19ffda9 100644
--- a/compress_generic.go
+++ b/compress_generic.go
@@ -7,6 +7,8 @@
 
 package blake2b
 
+import "encoding/binary"
+
 func compressGeneric(d *digest, p []uint8) {
 	h0, h1, h2, h3, h4, h5, h6, h7 := d.h[0], d.h[1], d.h[2], d.h[3], d.h[4], d.h[5], d.h[6], d.h[7]
 
@@ -30,9 +32,7 @@ func compressGeneric(d *digest, p []uint8) {
 		j := 0
 		var m [16]uint64
 		for i := range m {
-			m[i] = uint64(p[j]) | uint64(p[j+1])<<8 | uint64(p[j+2])<<16 |
-				uint64(p[j+3])<<24 | uint64(p[j+4])<<32 | uint64(p[j+5])<<40 |
-				uint64(p[j+6])<<48 | uint64(p[j+7])<<56
+			m[i] = binary.LittleEndian.Uint64(p[j : j+8])
 			j += 8
 		}
 
diff --git a/compress_noasm.go b/compress_noasm.go
index d3c6758..9c94594 100644
--- a/compress_noasm.go
+++ b/compress_noasm.go
@@ -1,4 +1,5 @@
-//+build !amd64 noasm appengine
+//go:build !amd64 || noasm || appengine
+// +build !amd64 noasm appengine
 
 /*
  * Minio Cloud Storage, (C) 2016 Minio, Inc.
diff --git a/cpuid.go b/cpuid.go
index a9f9550..30f3ee1 100644
--- a/cpuid.go
+++ b/cpuid.go
@@ -1,3 +1,4 @@
+//go:build (386 && !gccgo) || (amd64 && !gccgo)
 // +build 386,!gccgo amd64,!gccgo
 
 // Copyright 2016 Frank Wessels <fwessels@xs4all.nl>
diff --git a/cpuid_386.s b/cpuid_386.s
index fa38814..bc2da9b 100644
--- a/cpuid_386.s
+++ b/cpuid_386.s
@@ -1,7 +1,8 @@
-// Copyright (c) 2015 Klaus Post, released under MIT License. See LICENSE file.
-
+//go:build 386 && !gccgo
 // +build 386,!gccgo
 
+// Copyright (c) 2015 Klaus Post, released under MIT License. See LICENSE file.
+
 // func cpuid(op uint32) (eax, ebx, ecx, edx uint32)
 TEXT ·cpuid(SB), 7, $0
         XORL CX, CX
diff --git a/cpuid_amd64.s b/cpuid_amd64.s
index fb45a65..b651034 100644
--- a/cpuid_amd64.s
+++ b/cpuid_amd64.s
@@ -1,7 +1,8 @@
-// Copyright (c) 2015 Klaus Post, released under MIT License. See LICENSE file.
-
+//go:build amd64 && !gccgo
 // +build amd64,!gccgo
 
+// Copyright (c) 2015 Klaus Post, released under MIT License. See LICENSE file.
+
 // func cpuid(op uint32) (eax, ebx, ecx, edx uint32)
 TEXT ·cpuid(SB), 7, $0
         XORQ CX, CX
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..b151cf4
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module github.com/fumiama/blake2b-simd
+
+go 1.17