diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..19818e4
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,60 @@
+---
+name: CI
+on: [push]
+
+jobs:
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v2
+        with:
+          version: v1.31
+        env:
+          VERBOSE: "true"
+
+  tidy:
+    name: Tidy
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-go@v2
+        with:
+          go-version: 1.15
+      - name: Check if mods are tidy
+        run: make check-tidy
+
+  cov:
+    name: Code coverage
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-go@v2
+        with:
+          go-version: 1.15
+      - name: Publish coverage
+        uses: paambaati/codeclimate-action@v2.7.4
+        with:
+          coverageCommand: make cov
+          prefix: github.com/${{ github.repository }}
+          coverageLocations: |
+            ${{ github.workspace }}/coverage.out:gocov
+        env:
+          VERBOSE: "true"
+          GOMAXPROCS: 4
+          CC_TEST_REPORTER_ID: ${{ secrets.CC_TEST_REPORTER_ID }}
+
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-go@v2
+        with:
+          go-version: 1.15
+      - name: Run tests
+        run: make test
+        env:
+          VERBOSE: "true"
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..72bb60a
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+bin/*
+coverage.out
+tools/bin/*
diff --git a/.golangci.yml b/.golangci.yml
new file mode 100644
index 0000000..14b06be
--- /dev/null
+++ b/.golangci.yml
@@ -0,0 +1,75 @@
+linters-settings:
+  funlen:
+    lines: 100
+    statements: 150
+  gocyclo:
+    min-complexity: 20
+  golint:
+    min-confidence: 0
+  govet:
+    check-shadowing: true
+    enable-all: true
+  lll:
+    line-length: 80
+    tab-width: 4
+  maligned:
+    suggest-new: true
+  misspell:
+    locale: US
+
+linters:
+  disable-all: true
+  enable:
+    - bodyclose
+    - deadcode
+    - depguard
+    - dupl
+    - errcheck
+    - funlen
+    - gochecknoinits
+    - goconst
+    - gocritic
+    - gocyclo
+    - goimports
+    - golint
+    - goprintffuncname
+    - goprintffuncname
+    - gosec
+    - gosimple
+    - govet
+    - ineffassign
+    - lll
+    - misspell
+    - nakedret
+    - nlreturn
+    - noctx
+    - nolintlint
+    - scopelint
+    - sqlclosecheck
+    - staticcheck
+    - structcheck
+    - typecheck
+    - unconvert
+    - unused
+    - varcheck
+    - whitespace
+
+issues:
+  exclude:
+    - Using the variable on range scope `tt` in function literal
+    - Using the variable on range scope `tc` in function literal
+  exclude-rules:
+    - path: "_test\\.go"
+      linters:
+        - funlen
+    - source: "^//go:generate "
+      linters:
+        - lll
+    - source: "`json:"
+      linters:
+        - lll
+
+run:
+  timeout: 2m
+  allow-parallel-runners: true
+  modules-download-mode: readonly
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..8ab6b05
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,154 @@
+NAME := conver
+ROOT := $(CURDIR)
+SOURCES := $(shell find . -name "*.go" -or -name "go.mod" -or -name "go.sum" \
+	-or -name "Makefile")
+
+# Verbose output
+ifdef VERBOSE
+V = -v
+endif
+
+#
+# Environment
+#
+
+BINDIR := bin
+TOOLDIR := tools/bin
+
+# Global environment variables for all targets
+SHELL ?= /bin/bash
+SHELL := env \
+	GO111MODULE=on \
+	GOBIN=$(CURDIR)/$(TOOLDIR) \
+	CGO_ENABLED=1 \
+	PATH='$(CURDIR)/$(BINDIR):$(CURDIR)/$(TOOLDIR):$(PATH)' \
+	$(SHELL)
+
+#
+# Defaults
+#
+
+# Default target
+.DEFAULT_GOAL := build
+
+.PHONY: all
+all: lint test build
+
+#
+# Tools
+#
+
+TOOLS += $(TOOLDIR)/gobin
+gobin: $(TOOLDIR)/gobin
+$(TOOLDIR)/gobin:
+	GO111MODULE=off go get -u github.com/myitcv/gobin
+
+# external tool
+define tool # 1: binary-name, 2: go-import-path
+TOOLS += $(TOOLDIR)/$(1)
+
+.PHONY: $(1)
+$(1): $(TOOLDIR)/$(1)
+
+$(TOOLDIR)/$(1): $(TOOLDIR)/gobin Makefile
+	gobin $(V) "$(2)"
+endef
+
+$(eval $(call tool,gofumports,mvdan.cc/gofumpt/gofumports))
+$(eval $(call tool,golangci-lint,github.com/golangci/golangci-lint/cmd/golangci-lint@v1.31))
+
+.PHONY: tools
+tools: $(TOOLS)
+
+#
+# Build
+#
+
+BINARY=$(BINDIR)/$(NAME)
+LDFLAGS := -w -s
+
+VERSION ?= $(shell git describe --tags 2>/dev/null)
+GIT_SHA ?= $(shell git rev-parse --short HEAD 2>/dev/null)
+DATE ?= $(shell date +%s)
+
+ifeq ($(trim $(VERSION)),)
+	VERSION = dev
+endif
+
+.PHONY: build
+build: $(BINARY)
+
+$(BINARY): $(SOURCES)
+	go build $(V) -a -o "$@" -ldflags "$(LDFLAGS) \
+		-X main.Version=$(VERSION) \
+		-X main.Commit=$(GIT_SHA) \
+		-X main.Date=$(DATE)"
+
+#
+# Development
+#
+
+.PHONY: clean
+clean:
+	rm -rf $(BINS) $(TOOLS)
+	rm -f ./coverage.out ./go.mod.tidy-check ./go.sum.tidy-check
+
+.PHONY: test
+test:
+	go test $(V) -count=1 --race ./...
+
+.PHONY: lint
+lint: $(TOOLS)
+	$(info Running Go linters)
+	GOGC=off golangci-lint $(V) run
+
+.PHONY: format
+format: gofumports
+	gofumports -w .
+
+#
+# Coverage
+#
+
+.PHONY: cov
+cov: coverage.out
+
+.PHONY: cov-html
+cov-html: coverage.out
+	go tool cover -html=coverage.out
+
+.PHONY: cov-func
+cov-func: coverage.out
+	go tool cover -func=coverage.out
+
+coverage.out: $(SOURCES)
+	go test $(V) -covermode=count -coverprofile=coverage.out ./...
+
+#
+# Dependencies
+#
+
+.PHONY: deps
+deps:
+	$(info Downloading dependencies)
+	go mod download
+
+.PHONY: tidy
+tidy:
+	go mod tidy $(V)
+
+.PHONY: verify
+verify:
+	go mod verify
+
+.SILENT: check-tidy
+.PHONY: check-tidy
+check-tidy:
+	cp go.mod go.mod.tidy-check
+	cp go.sum go.sum.tidy-check
+	go mod tidy
+	-diff go.mod go.mod.tidy-check
+	-diff go.sum go.sum.tidy-check
+	-rm -f go.mod go.sum
+	-mv go.mod.tidy-check go.mod
+	-mv go.sum.tidy-check go.sum
diff --git a/main.go b/main.go
index 383963b..958ba21 100644
--- a/main.go
+++ b/main.go
@@ -4,9 +4,12 @@ import (
 	"bytes"
 	"errors"
 	"flag"
+	"fmt"
 	"html/template"
 	"io/ioutil"
 	"log"
+	"os"
+	"strconv"
 	"strings"
 	"time"
 
@@ -28,6 +31,12 @@ const changelogTemplate = `
 {{ end }}
 `
 
+var (
+	Version string
+	Commit  string
+	Date    string
+)
+
 type (
 	config struct {
 		// action
@@ -49,6 +58,8 @@ type (
 		// changelog config
 		ChangelogUpdate bool   `flag:"changelog-update" desc:"Update changelog"`
 		ChangelogPath   string `flag:"changelog-path" desc:"Changelog file path"`
+
+		PrintVersion bool `flag:"version" desc:"print version"`
 	}
 	changelogEntry struct {
 		Version         string
@@ -374,7 +385,7 @@ func changelogUpdate(c *config) error {
 	mergedBody := append(newBody.Bytes(), changelogBody...)
 
 	// and update file
-	return ioutil.WriteFile(c.ChangelogPath, mergedBody, 0644)
+	return ioutil.WriteFile(c.ChangelogPath, mergedBody, 0o644)
 }
 
 func fileUpdate(c *config) error {
@@ -394,7 +405,7 @@ func fileUpdate(c *config) error {
 	if err != nil {
 		return err
 	}
-	return ioutil.WriteFile(c.FilePath, []byte(newVersion), 0644)
+	return ioutil.WriteFile(c.FilePath, []byte(newVersion), 0o644)
 }
 
 func bumpAtLeastMinor(c *config) error {
@@ -423,6 +434,16 @@ func bumpVersion(currentVersion string, c *config) (string, error) {
 	return c.VersionPrefix + cleanNewVersion.String(), nil
 }
 
+func printVersion() {
+	if Date != "" {
+		ts, err := strconv.Atoi(Date)
+		if err == nil {
+			Date = time.Unix(int64(ts), 0).UTC().String()
+		}
+	}
+	fmt.Printf("conver %s (%s, %s)\n", Version, Commit, Date)
+}
+
 func main() {
 	c := &config{
 		FilePath:      "VERSION",
@@ -435,6 +456,11 @@ func main() {
 	}
 	flag.Parse()
 
+	if c.PrintVersion {
+		printVersion()
+		os.Exit(0)
+	}
+
 	actions := []func(*config) error{
 		autodetectBump,
 		bumpAtLeastMinor,