diff --git a/.circleci/config.yml b/.circleci/config.yml
deleted file mode 100644
index 7401bbe..0000000
--- a/.circleci/config.yml
+++ /dev/null
@@ -1,10 +0,0 @@
-version: 2
-jobs:
-  build:
-    docker:
-      - image: circleci/golang:latest
-    working_directory: /go/src/github.com/koron-go/dialsrv
-    steps:
-      - checkout
-      - run: go get -v -t -d ./...
-      - run: go test -v ./...
diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..7745062
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1 @@
+*	-text
diff --git a/.github/workflows/go.yml b/.github/workflows/go.yml
new file mode 100644
index 0000000..63e9b4b
--- /dev/null
+++ b/.github/workflows/go.yml
@@ -0,0 +1,29 @@
+name: Go
+
+on: [push]
+
+env:
+  GO_VERSION: '>=1.21.0'
+
+jobs:
+
+  build:
+    name: Build
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      matrix:
+        os: [ ubuntu-latest, macos-latest, windows-latest ]
+    steps:
+
+    - uses: actions/checkout@v4
+
+    - uses: actions/setup-go@v5
+      with:
+        go-version: ${{ env.GO_VERSION }}
+
+    - run: go test
+
+    - run: go build
+
+# based on: github.com/koron-go/_skeleton/.github/workflows/go.yml
diff --git a/.gitignore b/.gitignore
index ec90525..1519234 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,4 @@
+*~
+default.pgo
 tags
 tmp/
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..876c2e5
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,42 @@
+TEST_PACKAGE ?= ./...
+
+.PHONY: build
+build:
+	go build -gcflags '-e'
+
+.PHONY: test
+test:
+	go test $(TEST_PACKAGE)
+
+.PHONY: bench
+bench:
+	go test -bench $(TEST_PACKAGE)
+
+.PHONY: tags
+tags:
+	gotags -f tags -R .
+
+.PHONY: cover
+cover:
+	mkdir -p tmp
+	go test -coverprofile tmp/_cover.out $(TEST_PACKAGE)
+	go tool cover -html tmp/_cover.out -o tmp/cover.html
+
+.PHONY: checkall
+checkall: vet staticcheck
+
+.PHONY: vet
+vet:
+	go vet $(TEST_PACKAGE)
+
+.PHONY: staticcheck
+staticcheck:
+	staticcheck $(TEST_PACKAGE)
+
+.PHONY: clean
+clean:
+	go clean
+	rm -f tags
+	rm -f tmp/_cover.out tmp/cover.html
+
+# based on: github.com/koron-go/_skeleton/Makefile
diff --git a/README.md b/README.md
index b8e3e81..1091027 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 # koron-go/dialsrv
 
-[![GoDoc](https://godoc.org/github.com/koron-go/dialsrv?status.svg)](https://godoc.org/github.com/koron-go/dialsrv)
-[![CircleCI](https://img.shields.io/circleci/project/github/koron-go/dialsrv/master.svg)](https://circleci.com/gh/koron-go/dialsrv/tree/master)
+[![PkgGoDev](https://pkg.go.dev/badge/github.com/koron-go/dialsrv)](https://pkg.go.dev/github.com/koron-go/dialsrv)
+[![Actions/Go](https://github.com/koron-go/dialsrv/workflows/Go/badge.svg)](https://github.com/koron-go/dialsrv/actions?query=workflow%3AGo)
 [![Go Report Card](https://goreportcard.com/badge/github.com/koron-go/dialsrv)](https://goreportcard.com/report/github.com/koron-go/dialsrv)
 
 Dialer with SRV lookup.
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..bf1b7da
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module github.com/koron-go/dialsrv
+
+go 1.21
diff --git a/staticcheck.conf b/staticcheck.conf
new file mode 100644
index 0000000..8b70bd6
--- /dev/null
+++ b/staticcheck.conf
@@ -0,0 +1,5 @@
+# vim:set ft=toml:
+
+checks = ["all"]
+
+# based on: github.com/koron-go/_skeleton/staticcheck.conf