diff --git a/.codecov.yml b/.codecov.yml
index 6397d2b4..194d876f 100644
--- a/.codecov.yml
+++ b/.codecov.yml
@@ -45,6 +45,18 @@ coverage:
         <<: *projects
         flags:
           - "macos-1.15"
+      windows-1.13:
+        <<: *projects
+        flags:
+          - "windows-1.13"
+      windows-1.14:
+        <<: *projects
+        flags:
+          - "windows-1.14"
+      windows-1.15:
+        <<: *projects
+        flags:
+          - "windows-1.15"
     patch:
       default: false
       linux-1.13:
@@ -59,6 +71,12 @@ coverage:
         <<: *patch
       macos-1.15:
         <<: *patch
+      windows-1.13:
+        <<: *patch
+      windows-1.14:
+        <<: *patch
+      windows-1.15:
+        <<: *patch
     changes:
       default:
         if_ci_failed: error
@@ -73,6 +91,9 @@ coverage:
           - "macos-1.13"
           - "macos-1.14"
           - "macos-1.15"
+          - "windows-1.13"
+          - "windows-1.14"
+          - "windows-1.15"
 
 flags:
   linux-1.13:
@@ -99,6 +120,18 @@ flags:
     paths:
       - /
     carryforward: true
+  windows-1.13:
+    paths:
+      - /
+    carryforward: true
+  windows-1.14:
+    paths:
+      - /
+    carryforward: true
+  windows-1.15:
+    paths:
+      - /
+    carryforward: true
 
 comment:
   behavior: default
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index c7071cbe..cd35e678 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -8,6 +8,10 @@ on:
   pull_request:
     branches: "*"
 
+defaults:
+  run:
+    shell: bash
+
 jobs:
   test:
     strategy:
@@ -17,6 +21,8 @@ jobs:
           - ubuntu-20.04
           # https://github.com/actions/virtual-environments/blob/macOS-10.15/20201212.1/images/macos/macos-10.15-Readme.md
           - macos-10.15
+          # https://github.com/actions/virtual-environments/blob/win19/20201210.0/images/win/Windows2019-Readme.md
+          - windows-2019
         go-version:
           - 1.13.x
           - 1.14.x
@@ -41,38 +47,56 @@ jobs:
       with:
         fetch-depth: 2
 
-    - uses: actions/cache@v2
+    - name: Cache Go module and build cache
+      uses: actions/cache@v2
       with:
+        key: ${{ env.OS }}-go-${{ hashFiles('**/go.sum') }}
         path: |
           ~/go/pkg/mod              # Module download cache
           ~/.cache/go-build         # Build cache (Linux)
           ~/Library/Caches/go-build # Build cache (Mac)
           '%LocalAppData%\go-build' # Build cache (Windows)
-        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
         restore-keys: |
-          ${{ runner.os }}-go-
+          ${{ env.OS }}-go-
 
-    - name: Install nvim binary for Linux
-      if: runner.os == 'Linux'
-      run: |
-        curl -SLO https://github.com/go-nvim/neovim/releases/download/nightly/nvim-linux64.tar.gz
-        tar xzf nvim-linux64.tar.gz
-        mv nvim-linux64 /home/runner/nvim
-        echo "/home/runner/nvim/bin" >> $GITHUB_PATH
+    - name: Cache nvim binary for linux and darwin
+      uses: actions/cache@v2
+      id: cache-nvim
+      if: env.OS != 'windows'
+      with:
+        key: ${{ env.OS }}-nvim-${{ hashFiles('~/nvim/bin/nvim') }}
+        path: |
+          ~/nvim
+        restore-keys: |
+          ${{ env.OS }}-nvim-
 
-    - name: Install nvim binary for macOS
-      if: runner.os == 'MacOS'
+    - name: Cache nvim binary for Windows
+      uses: actions/cache@v2
+      id: cache-nvim-windows
+      if: env.OS == 'windows'
+      with:
+        key: ${{ env.OS }}-nvim-${{ hashFiles('~/nvim/nvim.exe') }}
+        path: |
+          ~/nvim
+        restore-keys: |
+          ${{ env.OS }}-nvim-
+
+    - name: Install nvim binary
+      uses: rhysd/action-setup-vim@v1
+      if: steps.cache-nvim.outputs.cache-hit != 'true' || steps.cache-nvim-windows.outputs.cache-hit != 'true'
+      with:
+        neovim: true
+        version: nightly
+
+    - name: gofmt
+      if: env.OS != 'windows'
       run: |
-        curl -SLO https://github.com/go-nvim/neovim/releases/download/nightly/nvim-macos.tar.gz
-        tar xzf nvim-macos.tar.gz
-        mv nvim-osx64 /Users/runner/nvim
-        echo "/Users/runner/nvim/bin" >> $GITHUB_PATH
+        diff -u <(echo -n) <(gofmt -s -d .)
 
     - name: Test and vet
       run: |
-        diff -u <(echo -n) <(gofmt -s -d .)
         go vet ./...
-        go test -v -race -covermode=atomic -coverpkg=./... -coverprofile=coverage.out ./...
+        go test -v -race -count=1 -covermode=atomic -coverpkg=./... -coverprofile=coverage.out ./...
 
     - uses: codecov/codecov-action@v1
       with:
diff --git a/nvim/nvim_test.go b/nvim/nvim_test.go
index 901857e6..d1717a4b 100644
--- a/nvim/nvim_test.go
+++ b/nvim/nvim_test.go
@@ -9,6 +9,7 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"runtime"
 	"sort"
 	"strings"
 	"sync/atomic"
@@ -20,11 +21,15 @@ func newChildProcess(tb testing.TB) (v *Nvim, cleanup func()) {
 	tb.Helper()
 
 	ctx := context.Background()
-	n, err := NewChildProcess(
+	opts := []ChildProcessOption{
 		ChildProcessArgs("-u", "NONE", "-n", "--embed", "--headless", "--noplugin"),
 		ChildProcessContext(ctx),
 		ChildProcessLogf(tb.Logf),
-	)
+	}
+	if runtime.GOOS == "windows" {
+		opts = append(opts, ChildProcessCommand("nvim.exe"))
+	}
+	n, err := NewChildProcess(opts...)
 	if err != nil {
 		tb.Fatal(err)
 	}
@@ -1554,6 +1559,10 @@ func clearBuffer(tb testing.TB, v *Nvim, buffer Buffer) {
 }
 
 func TestDial(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("not supported dial unix socket on windows GOOS")
+	}
+
 	t.Parallel()
 
 	v1, cleanup := newChildProcess(t)
diff --git a/nvim/plugin/register_test.go b/nvim/plugin/register_test.go
index d3e1e54d..574c9175 100644
--- a/nvim/plugin/register_test.go
+++ b/nvim/plugin/register_test.go
@@ -2,6 +2,7 @@ package plugin_test
 
 import (
 	"os"
+	"runtime"
 	"strings"
 	"testing"
 
@@ -14,10 +15,16 @@ func newEmbeddedPlugin(t *testing.T) (*plugin.Plugin, func()) {
 	if v := os.Getenv("VIM"); v != "" {
 		env = append(env, "VIM="+v)
 	}
-	v, err := nvim.NewChildProcess(
+
+	opts := []nvim.ChildProcessOption{
 		nvim.ChildProcessArgs("-u", "NONE", "-n", "--embed"),
 		nvim.ChildProcessEnv(env),
-		nvim.ChildProcessLogf(t.Logf))
+		nvim.ChildProcessLogf(t.Logf),
+	}
+	if runtime.GOOS == "windows" {
+		opts = append(opts, nvim.ChildProcessCommand("nvim.exe"))
+	}
+	v, err := nvim.NewChildProcess(opts...)
 	if err != nil {
 		t.Fatal(err)
 	}