feat: Windows Compability

.gitignore

@@ -50,4 +50,8 @@ examples/*/size.json
 ### AI Tooling ###
 .claude/settings.local.json
 examples/**/.claude
+
+## Local Development ##
+.env
+examples/*/size.json
 .gemini/

buildkit/build.go

@@ -273,7 +273,10 @@ func BuildWithBuildkitClient(appDir string, plan *plan.BuildPlan, opts BuildWith
 }
 
 func getImageName(appDir string) string {
-	parts := strings.Split(appDir, string(os.PathSeparator))
+	// Normalize path separators to forward slash for consistent splitting
+	// This handles both Unix (/path/to/app) and Windows (C:\path\to\app) paths
+	normalized := strings.ReplaceAll(appDir, "\\", "/")
+	parts := strings.Split(normalized, "/")
 	name := parts[len(parts)-1]
 	if name == "" {
 		name = "railpack-app" // Fallback if path ends in separator

buildkit/build_llb/build_graph.go

@@ -6,7 +6,7 @@ import (
 	"fmt"
 	"maps"
 	"os"
-	"path/filepath"
+	"path"
 	"slices"
 	"strings"
 
@@ -333,7 +333,8 @@ func (g *BuildGraph) convertFileCommandToLLB(cmd plan.FileCommand, state llb.Sta
 	}
 
 	// Create parent directories for the file
-	parentDir := filepath.Dir(cmd.Path)
+	// Use path.Dir for container paths (always forward slash)
+	parentDir := path.Dir(cmd.Path)
 	if parentDir != "/" {
 		s := state.File(llb.Mkdir(parentDir, 0755, llb.WithParents(true)))
 		state = s

buildkit/build_llb/layers.go

@@ -3,7 +3,6 @@ package build_llb
 import (
 	"fmt"
 	"path"
-	"path/filepath"
 	"slices"
 	"strings"
 
@@ -260,18 +259,21 @@ func hasPathOverlap(paths1, paths2 []string) bool {
 // resolvePaths determines source and destination paths based on the include path and whether it's local.
 // For local paths, only the basename is preserved when copying to /app directory.
 // For container paths, the full relative path structure is preserved under /app.
+// Note: Uses path.Join (not filepath.Join) for container paths to ensure forward slashes on all platforms.
 func resolvePaths(include string, isLocal bool) (srcPath, destPath string) {
 	if isLocal {
 		// convert a local path reference to fully qualified container path
-		return include, filepath.Join("/app", filepath.Base(include))
+		// Use path.Join and path.Base for container paths (always forward slash)
+		return include, path.Join("/app", path.Base(include))
 	}
 
 	switch {
 	case include == "." || include == "/app" || include == "/app/":
 		return "/app", "/app"
-	case filepath.IsAbs(include):
+	case path.IsAbs(include):
 		return include, include
 	default:
-		return filepath.Join("/app", include), filepath.Join("/app", include)
+		// Use path.Join for container paths (always forward slash)
+		return path.Join("/app", include), path.Join("/app", include)
 	}
 }

buildkit/build_test.go

@@ -1,7 +1,6 @@
 package buildkit
 
 import (
-	"path/filepath"
 	"testing"
 )
 
@@ -38,7 +37,7 @@ func TestGetImageName(t *testing.T) {
 		},
 		{
 			name:     "path ending with separator",
-			appDir:   "/path/to/myapp" + string(filepath.Separator),
+			appDir:   "/path/to/myapp/",
 			expected: "railpack-app",
 		},
 	}

core/generate/context.go

@@ -65,7 +65,7 @@ func (c CommandWrapper) IsSpread() bool {
 }
 
 func NewGenerateContext(app *a.App, env *a.Environment, config *config.Config, logger *logger.Logger) (*GenerateContext, error) {
-	resolver, err := resolver.NewResolver(mise.InstallDir)
+	resolver, err := resolver.NewResolver(mise.GetInstallDir())
 	if err != nil {
 		return nil, err
 	}

core/generate/mise_step_builder.go

@@ -120,7 +120,7 @@ func (b *MiseStepBuilder) SkipMiseInstall(name resolver.PackageRef) {
 // GetMisePackageVersions gets all package versions from mise that are defined in the app directory environment
 // this can include additional packages defined outside the app directory, but we filter those out
 func (b *MiseStepBuilder) GetMisePackageVersions(ctx *GenerateContext) (map[string]*MisePackageInfo, error) {
-	miseInstance, err := mise.New(mise.InstallDir)
+	miseInstance, err := mise.New(mise.GetInstallDir())
 	if err != nil {
 		return nil, err
 	}

core/mise/mise.go

@@ -19,11 +19,27 @@ import (
 )
 
 const (
-	InstallDir                = "/tmp/railpack/mise"
-	TestInstallDir            = "/tmp/railpack/mise-test"
+	DefaultInstallDir         = "/tmp/railpack/mise"
+	DefaultTestInstallDir     = "/tmp/railpack/mise-test"
 	IdiomaticVersionFileTools = "python,node,ruby,elixir,go,java,yarn"
 )
 
+// GetInstallDir returns the mise install directory, checking RAILPACK_MISE_DIR env var first
+func GetInstallDir() string {
+	if envDir := os.Getenv("RAILPACK_MISE_DIR"); envDir != "" {
+		return envDir
+	}
+	return DefaultInstallDir
+}
+
+// GetTestInstallDir returns the mise test install directory
+func GetTestInstallDir() string {
+	if envDir := os.Getenv("RAILPACK_MISE_TEST_DIR"); envDir != "" {
+		return envDir
+	}
+	return DefaultTestInstallDir
+}
+
 type Mise struct {
 	binaryPath  string
 	cacheDir    string

core/providers/golang/golang.go

@@ -2,6 +2,7 @@ package golang
 
 import (
 	"fmt"
+	"path"
 	"path/filepath"
 	"strings"
 
@@ -145,9 +146,11 @@ func (p *GoProvider) InstallGoDeps(ctx *generate.GenerateContext, install *gener
 
 	workspacePackages := p.GoWorkspacePackages(ctx)
 	for _, pkgPath := range workspacePackages {
-		install.AddCommand(plan.NewCopyCommand(filepath.Join(pkgPath, "go.mod")))
+		// Use path.Join for container paths (always forward slash)
+		install.AddCommand(plan.NewCopyCommand(path.Join(pkgPath, "go.mod")))
+		// Use filepath.Join for host filesystem checks
 		if ctx.App.HasFile(filepath.Join(pkgPath, "go.sum")) {
-			install.AddCommand(plan.NewCopyCommand(filepath.Join(pkgPath, "go.sum")))
+			install.AddCommand(plan.NewCopyCommand(path.Join(pkgPath, "go.sum")))
 		}
 	}
 

core/providers/node/workspace.go

@@ -2,7 +2,7 @@ package node
 
 import (
 	"fmt"
-	"path/filepath"
+	"path"
 
 	"github.com/railwayapp/railpack/core/app"
 )
@@ -68,7 +68,8 @@ func (w *Workspace) findWorkspacePackages(app *app.App) error {
 				continue
 			}
 
-			dir := filepath.Dir(match)
+			// Use path.Dir for consistent forward slash paths
+			dir := path.Dir(match)
 			w.Packages = append(w.Packages, &WorkspacePackage{
 				Path:        dir,
 				PackageJson: packageJson,
@@ -95,7 +96,7 @@ func convertWorkspacePattern(pattern string) string {
 	}
 
 	// Direct path or other pattern, just append package.json
-	return filepath.Join(pattern, "package.json")
+	return path.Join(pattern, "package.json")
 }
 
 // readPackageJson reads a package.json file from the given path

core/resolver/resolver_test.go

@@ -19,7 +19,7 @@ func TestPackagesWithDefaults(t *testing.T) {
 }
 
 func TestPackageResolver(t *testing.T) {
-	resolver, err := NewResolver(mise.TestInstallDir)
+	resolver, err := NewResolver(mise.GetTestInstallDir())
 	require.NoError(t, err)
 
 	// Set up Node.js
@@ -80,7 +80,7 @@ func TestPackageResolver(t *testing.T) {
 }
 
 func TestPackageResolverWithPreviousVersions(t *testing.T) {
-	resolver, err := NewResolver(mise.TestInstallDir)
+	resolver, err := NewResolver(mise.GetTestInstallDir())
 	require.NoError(t, err)
 
 	resolver.SetPreviousVersion("node", "16")
@@ -105,7 +105,7 @@ func TestPackageResolverWithPreviousVersions(t *testing.T) {
 }
 
 func TestResolvingPackagesNotAvailable(t *testing.T) {
-	resolver, err := NewResolver(mise.TestInstallDir)
+	resolver, err := NewResolver(mise.GetTestInstallDir())
 	require.NoError(t, err)
 
 	node := resolver.Default("node", "18.20")

mise.toml

@@ -1,6 +1,9 @@
 [env]
 BUILDKIT_HOST = "docker-container://buildkit"
 RAILPACK_MISE_VERSION = "{{exec(command='cat core/mise/version.txt')}}"
+# Mise installation directory (Windows users: change to e.g. C:\tmp\railpack\mise)
+RAILPACK_MISE_DIR = "/tmp/railpack/mise"
+RAILPACK_MISE_TEST_DIR = "/tmp/railpack/mise-test"
 
 _.path = './bin'