Add support for build tags to the wails project schema and update pro… (#4439)

* Add support for build tags to the wails project schema and update project-config documentation for guidance

* Support project tags in dev mode

* Satisfy coderabbit nitpick relating to error variable name

* Added changelog entry for `build:tags` project feature

---------

Co-authored-by: symball <contact@simonball.me>
Co-authored-by: Lea Anthony <lea.anthony@gmail.com>

v2/cmd/wails/build.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"github.com/wailsapp/wails/v2/pkg/commands/buildtags"
 	"os"
 	"runtime"
 	"strings"
@@ -59,6 +60,13 @@ func buildApplication(f *flags.Build) error {
 		f.GarbleArgs = projectOptions.GarbleArgs
 	}
 
+	projectTags, err := buildtags.Parse(projectOptions.BuildTags)
+	if err != nil {
+		return err
+	}
+	userTags := f.GetTags()
+	compiledTags := append(projectTags, userTags...)
+
 	// Create BuildOptions
 	buildOptions := &build.Options{
 		Logger:            logger,
@@ -76,7 +84,7 @@ func buildApplication(f *flags.Build) error {
 		IgnoreFrontend:    f.SkipFrontend,
 		Compress:          f.Upx,
 		CompressFlags:     f.UpxFlags,
-		UserTags:          f.GetTags(),
+		UserTags:          compiledTags,
 		WebView2Strategy:  f.GetWebView2Strategy(),
 		TrimPath:          f.TrimPath,
 		RaceDetector:      f.RaceDetector,
@@ -106,7 +114,7 @@ func buildApplication(f *flags.Build) error {
 		{"Package", bool2Str(!f.NoPackage)},
 		{"Clean Bin Dir", bool2Str(f.Clean)},
 		{"LDFlags", f.LdFlags},
-		{"Tags", "[" + strings.Join(f.GetTags(), ",") + "]"},
+		{"Tags", "[" + strings.Join(compiledTags, ",") + "]"},
 		{"Race Detector", bool2Str(f.RaceDetector)},
 	}...)
 	if len(buildOptions.OutputFile) > 0 && f.GetTargets().Length() == 1 {

v2/cmd/wails/internal/dev/dev.go

@@ -76,10 +76,15 @@ func Application(f *flags.Dev, logger *clilogger.CLILogger) error {
 		return err
 	}
 
-	buildOptions.UserTags = userTags
-
 	projectConfig := f.ProjectConfig()
 
+	projectTags, err := buildtags.Parse(projectConfig.BuildTags)
+	if err != nil {
+		return err
+	}
+	compiledTags := append(projectTags, userTags...)
+	buildOptions.UserTags = compiledTags
+
 	// Setup signal handler
 	quitChannel := make(chan os.Signal, 1)
 	signal.Notify(quitChannel, os.Interrupt, syscall.SIGTERM)

v2/internal/project/project.go

@@ -42,6 +42,9 @@ type Project struct {
 	// Build directory
 	BuildDir string `json:"build:dir"`
 
+	// BuildTags Extra tags to process during build
+	BuildTags string `json:"build:tags"`
+
 	// The output filename
 	OutputFilename string `json:"outputfilename"`
 

website/docs/reference/project-config.mdx

@@ -18,6 +18,8 @@ The project config resides in the `wails.json` file in the project directory. Th
   "reloaddirs": "",
   // The directory where the build files reside. Defaults to 'build'
   "build:dir": "",
+  // Additional tags to include at build time regardless of environment
+  "build:tags": "",
   // Relative path to the frontend directory. Defaults to 'frontend'
   "frontend:dir": "",
   // The command to install node dependencies, run in the frontend directory - often `npm install`

website/src/pages/changelog.mdx

@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Configure Vite timeout by @leaanthony in [PR](https://github.com/wailsapp/wails/pull/4374)
 - Added `ContentProtection` option to allow hiding the application window from screen sharing software [#4241](https://github.com/wailsapp/wails/pull/4241) by [@Taiterbase](https://github.com/Taiterbase)
+- Added `build:tags` to project specification for automatically adding compilation tags by @symball in [PR](https://github.com/wailsapp/wails/pull/4439)
 
 ## v2.10.2 - 2025-07-06