feat: add asobi init --template backend

cmd/asobi/main.go

@@ -89,8 +89,9 @@ Usage:
   asobi logout                 Clear stored credentials
   asobi whoami                 Show current credential info
   asobi init [dir]             Scaffold a starter Lua game
-  asobi init [dir] --template <engine>
-                              Scaffold a runnable demo (defold|godot|unity)
+  asobi init [dir] --template <name>
+                              Scaffold a runnable project:
+                              defold|godot|unity (client demo) or backend (server only)
   asobi dev [--port N] [--dir <lua>]
                               Run a local backend for your Lua game (Docker)
   asobi games                  List your tenant's games
@@ -688,7 +689,7 @@ func cmdInit() {
 	if engine != "" {
 		t, ok := template.Get(engine)
 		if !ok {
-			fatal("unknown template %q; available: %s", engine, strings.Join(template.Engines(), ", "))
+			fatal("unknown template %q; available: %s", engine, strings.Join(template.Names(), ", "))
 		}
 		fmt.Printf("Fetching the %s template into %s ...\n", t.Name, dir)
 		created, err := template.Fetch(engine, dir)
@@ -705,7 +706,12 @@ func cmdInit() {
 		if dir != "." {
 			step("cd " + dir)
 		}
-		step("Open README.md - it walks through starting the backend and opening the project in " + t.Name + ".")
+		if engine == "backend" {
+			step("docker compose up -d   (asobi_lua image + Postgres on :8084)")
+			step("Open README.md - it covers the managed (asobi deploy) vs local (compose) paths and adding modes in lua/config.lua.")
+		} else {
+			step("Open README.md - it walks through starting the backend and opening the project in " + t.Name + ".")
+		}
 		return
 	}
 

internal/scaffold/scaffold.go

@@ -63,9 +63,19 @@ The game logic lives in ` + "`lua/match.lua`" + `. The engine loads it as the
 ` + "`handle_input`, `tick` and `get_state`. `match_size`" + ` sets how many players
 are needed to start a match.
 
-## Deploy
+## Run it locally
 
-Run these from this directory.
+No account, no keys - runs the asobi_lua image + Postgres in Docker:
+
+` + "```bash" + `
+asobi dev
+` + "```" + `
+
+Edit ` + "`lua/`" + ` and it hot-reloads. API + WebSocket on http://localhost:8084.
+
+## Deploy to Asobi Cloud
+
+Managed hosting - this needs a login:
 
 ` + "```bash" + `
 asobi login
@@ -74,6 +84,29 @@ asobi create <env>     # e.g. asobi create prod
 asobi deploy <env> lua
 ` + "```" + `
 
+## Multiple game modes
+
+To run more than the ` + "`default`" + ` mode, add a ` + "`lua/config.lua`" + ` manifest
+mapping mode names to files:
+
+` + "```lua" + `
+return {
+    default = "match.lua",
+    ranked  = "ranked.lua"
+}
+` + "```" + `
+
+Clients pick a mode with ` + "`matchmaker.add {mode = \"ranked\"}`" + `.
+
+## A full backend example
+
+Want the whole picture - Docker Compose, the mode manifest, all the
+` + "`ASOBI_*`" + ` env vars in one runnable repo?
+
+` + "```bash" + `
+asobi init mybackend --template backend
+` + "```" + `
+
 ## Connect a client
 
 Defold quickstart: https://github.com/widgrensit/asobi-defold

internal/scaffold/scaffold_test.go

@@ -50,6 +50,11 @@ func TestInitCreatesWorkingGame(t *testing.T) {
 			t.Fatalf("README.md missing deploy step %q", step)
 		}
 	}
+	for _, hint := range []string{"asobi dev", "config.lua", "--template backend"} {
+		if !strings.Contains(string(readme), hint) {
+			t.Fatalf("README.md missing %q", hint)
+		}
+	}
 }
 
 func TestInitRefusesToOverwrite(t *testing.T) {

internal/template/template.go

@@ -1,7 +1,8 @@
-// Package template scaffolds a runnable client+backend game project by fetching
-// one of the asobi demo repositories at a pinned commit. The demos are the single
-// source of truth (no parallel templates to drift); each carries its own README
-// documenting how to run the backend and open the project in its engine.
+// Package template scaffolds a runnable game project by fetching one of the asobi
+// demo repositories at a pinned commit: an engine template (client + backend) or
+// the backend template (server-Lua backend only). The repos are the single source
+// of truth (no parallel templates to drift); each carries its own README
+// documenting how to run the backend and, for engine templates, open the project.
 package template
 
 import (
@@ -27,18 +28,20 @@ type Template struct {
 }
 
 var registry = map[string]Template{
-	"defold": {Repo: "asobi-defold-demo", Ref: "v0.2.0", Name: "Defold"},
-	"godot":  {Repo: "asobi-godot-demo", Ref: "v0.2.0", Name: "Godot"},
-	"unity":  {Repo: "asobi-unity-demo", Ref: "v0.2.0", Name: "Unity"},
+	"defold":  {Repo: "asobi-defold-demo", Ref: "v0.2.0", Name: "Defold"},
+	"godot":   {Repo: "asobi-godot-demo", Ref: "v0.2.0", Name: "Godot"},
+	"unity":   {Repo: "asobi-unity-demo", Ref: "v0.2.0", Name: "Unity"},
+	"backend": {Repo: "sdk_demo_backend", Ref: "v0.1.0", Name: "Backend"},
 }
 
 const (
 	maxFiles = 20000
 	maxBytes = 500 << 20 // 500 MiB, generous for a Unity demo
 )
 
-// Engines returns the known template engine keys, sorted.
-func Engines() []string {
+// Names returns the known template names, sorted (e.g. defold, godot, unity,
+// backend).
+func Names() []string {
 	keys := make([]string, 0, len(registry))
 	for k := range registry {
 		keys = append(keys, k)
@@ -58,7 +61,7 @@ func Get(engine string) (Template, bool) {
 func Fetch(engine, dir string) ([]string, error) {
 	t, ok := registry[engine]
 	if !ok {
-		return nil, fmt.Errorf("unknown template %q; available: %s", engine, strings.Join(Engines(), ", "))
+		return nil, fmt.Errorf("unknown template %q; available: %s", engine, strings.Join(Names(), ", "))
 	}
 	if err := requireEmptyDir(dir); err != nil {
 		return nil, err

internal/template/template_test.go

@@ -51,11 +51,11 @@ func makeTarGz(t *testing.T, entries []entry) []byte {
 	return buf.Bytes()
 }
 
-func TestEnginesKnown(t *testing.T) {
-	got := Engines()
-	want := []string{"defold", "godot", "unity"}
+func TestNamesKnown(t *testing.T) {
+	got := Names()
+	want := []string{"backend", "defold", "godot", "unity"}
 	if !reflect.DeepEqual(got, want) {
-		t.Fatalf("Engines() = %v, want %v", got, want)
+		t.Fatalf("Names() = %v, want %v", got, want)
 	}
 	for _, e := range want {
 		if _, ok := Get(e); !ok {