chore: Devvit-Vorlage Bare und CLAUDE.md

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.github/dependabot.yml

@@ -0,0 +1,26 @@
+# Dependabot configuration to update npm packages weekly
+version: 2
+updates:
+  - package-ecosystem: "npm"
+    directory: "/" # Location of your package.json and package-lock.json
+    schedule:
+      interval: "cron"
+      cronjob: "0 17 * * 1,2" # At 5pm on Monday and Tuesday - https://crontab.guru/
+      timezone: "America/New_York"
+    open-pull-requests-limit: 10 # Optional: prevents PR spam by limiting active updates
+    ignore:
+      - dependency-name: "@types/node"
+        update-types: ["version-update:semver-major"]
+    cooldown:
+      exclude:
+        - "devvit"
+        - "@devvit/*"
+    groups:
+      devvit:
+        patterns:
+          - "devvit"
+          - "@devvit/*"
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"

.github/workflows/ci.yaml

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+# https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-nodejs
+name: CI
+
+on:
+  push:
+    branches: ["main"]
+  pull_request:
+    branches: ["main"]
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
+      - name: Install Node.js
+        uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
+        with:
+          node-version: 24.18.0
+      - name: Install Dependencies
+        run: npm install --no-fund
+      - parallel:
+          - name: Typecheck
+            run: npm run test:types
+          - name: Lint
+            run: npm run lint
+          - name: Unit Test
+            run: npm run test:unit
+          - name: Build
+            run: npm run build

.gitignore

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+/node_modules/
+/dist/
+/public/*.js*
+/.env

.nvmrc

@@ -0,0 +1 @@
+24.18.0

.vscode/extensions.json

@@ -0,0 +1 @@
+{"recommendations": ["biomejs.biome"]}

.vscode/settings.json

@@ -0,0 +1,5 @@
+{
+  "editor.defaultFormatter": "biomejs.biome",
+  "editor.codeActionsOnSave": {"source.organizeImports.biome": "explicit"},
+  "js/ts.tsdk.path": "node_modules/typescript/lib"
+}

CLAUDE.md

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+# CLAUDE.md – Ninelands für Reddit (Devvit)
+
+Diese Datei lädt Claude Code in jeder Sitzung. Sie hält fest, **was** dieses Projekt ist, **wie** gearbeitet wird und
+**wo** wir stehen. Stand: 2026-11-13, frisch angelegt aus der Devvit-Vorlage **Bare**.
+
+## Projekt
+
+- **Ninelands auf Reddit**: eine Basic-Version von [Ninelands](https://ninelands.stackteam.at) als Reddit-Spiel
+  (Devvit Web) für den Jam **Reddit Game of the Day 2026** – https://redditgameofday2026.devpost.com/ (Regeln:
+  `/rules`). Besitzer: Lukas Müllner (StackTeam). Mit dem Besitzer **Deutsch** sprechen.
+- App-Name in `devvit.json`: `ninelands-game`. Ordner: `/data/Documents/projects/ninelands-game`.
+- Geplantes Repo: `DieLustigeTierwesen/ninelands-reddit` auf `git.stackteam.at` (Forgejo, noch nicht angelegt).
+- **Was die Basic-Version können soll, ist noch offen** – das klären wir zuerst gemeinsam (Spieldesign entscheidet der
+  Besitzer). Vorher nichts Spielerisches bauen.
+
+## Woher Fragen beantwortet werden
+
+- **Das Hauptspiel** (Regeln, Engine, Gestaltung): Repo `DieLustigeTierwesen/DokuHive`, lokal
+  `/data/Documents/projects/hivedoku` – dort `README.md`, `hicedoku_plan.md` (Entscheidungen „as built“),
+  Leitfaden `guide/chapters/`. Bei Fragen zu Regeln oder Absicht **dort nachlesen**, nicht raten.
+- **Allgemeiner Spiele-Blueprint** (Arbeitsweise, Fallstricke, Releases): Repo `DieLustigeTierwesen/game-blueprint`,
+  lokal `/data/Documents/projects/game-blueprint/AGENT.md`. Erkenntnisse, die für künftige Spiele gelten (z. B. „wie
+  baut man ein Devvit-Spiel“), dort nachtragen.
+
+## Grenzen zum Hauptspiel
+
+- **In `/data/Documents/projects/hivedoku` nichts ändern, committen oder pushen.** Jeder Push auf dessen `main`
+  deployt die Live-Seite; Releases dort (itch, Desktop, Android) laufen über `npm run release` und gehören nicht zu
+  diesem Projekt.
+- Die Engine von Ninelands (`hivedoku/src/core`, reines TypeScript ohne DOM/Server, seeded RNG, `applyMove`,
+  `legalMoves`, Replay) darf übernommen werden – als **Kopie mit festem Stand** (z. B. Sync-Skript, das `src/core` von
+  einem Ninelands-Tag holt und den Tag notiert). Die Kopie hier **nicht von Hand ändern**; Änderungen an der Engine
+  gehören ins Hauptspiel. Achtung: `src/core` importiert JSON aus `../campaign/` und `../puzzles/` – nur mitnehmen,
+  was die Basic-Version braucht.
+- **Lizenz klären, bevor Engine-Code kopiert wird:** Ninelands steht unter **GPL-3.0**, diese Vorlage unter
+  **BSD-3-Clause** (`LICENSE` stammt aus der Devvit-Vorlage). Kopierte GPL-Teile machen das Ganze GPL – die Lizenz
+  entscheidet der Besitzer (auch, ob der Jam eine Open-Source-Lizenz verlangt).
+
+## Jam – vor der Arbeit prüfen
+
+Die Devpost-Seiten blockieren automatische Abrufe (403). Der Besitzer liefert die Regeln; offen sind:
+
+- Darf ein **bestehendes Spiel** (Basic-Version von Ninelands) eingereicht werden, oder nur während des Jams
+  Entstandenes? Muss Vorhandenes angegeben werden?
+- Abgabefrist, Pflichtteile der Einreichung (Video, Repo-Link, Test-Subreddit, Beschreibung), Bewertungskriterien,
+  Regeln zu KI-Nutzung und Fremdcode.
+
+Ergebnis hier unter „Stand“ festhalten.
+
+## Technik (Vorlage Bare)
+
+- Devvit Web: Client `src/client/` (Splash `splash.ts` → `public/splash.html`, Spiel `game.ts` → `public/game.html`),
+  Server `src/server/` (`index.ts`, `server.ts`, Speicher `db.ts`), gemeinsame Typen `src/shared/api.ts`.
+  Gebaut mit **esbuild** nach `public/` und `dist/server/`.
+- Werkzeuge der Vorlage beibehalten: **Biome** (Lint + Format, `npm run lint` / `npm run format`) statt Prettier,
+  Tests mit `node --test` (`*.test.ts`), Typprüfung `tsc --build`.
+- Befehle: `npm run test` (Typen, Lint, Unit-Tests, Build – **das ist die Prüfung vor jedem Merge**),
+  `npm run playtest [r/sub]` (baut, lädt hoch, installiert im Test-Subreddit), `npm run publish` (lädt hoch und
+  stellt einen **Review-Antrag** bei Reddit – nur nach Rückfrage beim Besitzer).
+- Node 24 über nvm (global ist 20): Befehle mit `source ~/.nvm/nvm.sh && nvm use 24 >/dev/null &&` beginnen.
+- Kein eigener Server, keine eigene Datenbank, keine eigenen Konten: Spieler sind Reddit-Nutzer, gespeichert wird
+  über Devvit (Redis). Externe Netzaufrufe sind bei Devvit eingeschränkt – vor jeder Idee, die das Ninelands-Backend
+  anspricht, in der Devvit-Doku prüfen (https://developers.reddit.com/docs).
+- Aktuelle Devvit-Doku lesen, bevor etwas gebaut wird – die Plattform ändert sich schnell; nicht aus dem Gedächtnis
+  arbeiten.
+- `.github/workflows/ci.yaml` stammt aus der Vorlage. Forgejo führt `.github/workflows` aus, wenn es kein
+  `.forgejo/workflows` gibt; `runs-on: ubuntu-latest` ist der gemeinsame Hetzner-Runner (für `npm run test` reicht er).
+
+## Arbeitsweise
+
+- **Ein Branch pro Änderung** (`feat/…`, `fix/…`, `chore/…`), auch für Doku.
+- **Merge nur, wenn `npm run test` mit Exit-Code 0 endet.** Ausgabe in eine Log-Datei, dann `$?` prüfen – nie mit
+  `| grep … &&` oder `;` verketten. Muster: `npm run test > log 2>&1; code=$?; if [ $code -eq 0 ]; then … merge; fi`.
+- `git merge --no-ff`, Branch löschen, `main` pushen (sobald ein Remote existiert), im Bericht erwähnen.
+- Conventional Commits; Ende jeder Nachricht: `Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>`.
+- Code-Kommentare auf Deutsch.
+- Größere Entscheidungen und Fallstricke in `PLAN.md` (Abschnitt „as built“, Deutsch) festhalten; am Ende eines
+  Schritts Erkenntnisse von sich aus nennen.
+- Innerhalb eines vereinbarten Plans selbstständig weitermachen; anhalten bei Spieldesign, Geschmack, externen Konten,
+  Geld, Lizenz und allem, was öffentlich wird (`devvit publish`, Posts in echten Subreddits).
+- **Kein Geld ausgeben.**
+
+## Geheimnisse – nie ausgeben, nie committen
+
+- Devvit-Token `~/.devvit/token` (Reddit-Anmeldung des Besitzers): nie lesen, ausgeben oder kopieren; die
+  `devvit`-Befehle nutzen ihn selbst.
+- Forgejo-Token `~/.config/forgejo-token`: nur innerhalb von Befehlen lesen.
+- Nutzer sollen nie Schlüssel in den Chat kopieren.
+
+## Stand (2026-11-13)
+
+- Vorlage **Bare** angelegt (`npm create devvit`), `git init` ohne Commit, kein Remote.
+- Nächste Schritte:
+  1. Erster Commit der Vorlage (+ diese Datei); Repo `DieLustigeTierwesen/ninelands-reddit` anlegen (nach Rückfrage)
+     und pushen.
+  2. Jam-Regeln vom Besitzer übernehmen (siehe oben).
+  3. Mit dem Besitzer festlegen, was die Basic-Version kann.
+  4. Lizenz entscheiden, dann Engine-Kopie + Sync-Skript.
+
+Diese Datei bei neuen Arbeitsregeln und Entscheidungen aktualisieren.

LICENSE

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+# License (BSD-3-Clause)
+
+Copyright (c) 2025 Reddit Inc.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+3. Neither the name of the copyright holder nor the names of its contributors
+   may be used to endorse or promote products derived from this software without
+   specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
+DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

biome.jsonc

@@ -0,0 +1,37 @@
+{
+  "$schema": "https://biomejs.dev/schemas/2.6.4/schema.json",
+  "css": {"formatter": {"enabled": true, "quoteStyle": "single"}},
+  "files": {"includes": ["**", "!dist/", "!public/*.js*"]},
+  "formatter": {
+    "bracketSpacing": false,
+    "enabled": true,
+    "indentStyle": "space"
+  },
+  "html": {"formatter": {"enabled": true}},
+  "javascript": {
+    "formatter": {
+      "arrowParentheses": "asNeeded",
+      "jsxQuoteStyle": "single",
+      "quoteStyle": "single",
+      "semicolons": "asNeeded"
+    }
+  },
+  "linter": {
+    "domains": {"project": "all"},
+    "rules": {
+      "correctness": {
+        // Biome resolves conditional exports without the browser condition,
+        // which reports false positives for `@devvit/web/client` named exports.
+        "noUnresolvedImports": "off"
+      },
+      "nursery": {
+        "noFloatingPromises": "error",
+        "noMisusedPromises": "error",
+        "recommended": true
+      },
+      "style": {"noInferrableTypes": "off"},
+      "suspicious": {"noImplicitAnyLet": "off"}
+    }
+  },
+  "vcs": {"enabled": true, "clientKind": "git", "useIgnoreFile": true}
+}

devvit.json

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+{
+  "$schema": "https://developers.reddit.com/schema/config-file.v1.json",
+  "name": "ninelands-game",
+  "post": {
+    "entrypoints": {
+      "default": {
+        "entry": "splash.html"
+      },
+      "game": {
+        "entry": "game.html"
+      }
+    }
+  },
+  "server": {},
+  "menu": {
+    "items": [
+      {
+        "label": "[ninelands-game] New Post",
+        "description": "Create a new ninelands-game post.",
+        "location": "subreddit",
+        "endpoint": "/internal/on/menu/new-post"
+      }
+    ]
+  },
+  "triggers": {
+    "onAppInstall": "/internal/on/app/install"
+  },
+  "scripts": {
+    "dev": "npm run watch"
+  }
+}

package.json

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+{
+  "private": true,
+  "name": "ninelands-game",
+  "version": "0.0.0",
+  "license": "BSD-3-Clause",
+  "type": "module",
+  "scripts": {
+    "build": "npm run build:client -- --metafile=dist/client.meta.json --minify && npm run build:server -- --metafile=dist/server.meta.json --minify",
+    "build:client": "esbuild --bundle --log-level=warning --sourcemap=linked --target=es2023 --format=esm --outdir=public --platform=browser src/client/splash.ts src/client/game.ts",
+    "build:server": "esbuild --bundle --log-level=warning --sourcemap=linked --target=es2023 --format=cjs --outdir=dist/server --platform=node src/server/index.ts",
+    "clean": "rm -rf dist/ public/*.js*",
+    "format": "npm run lint -- --fix",
+    "lint": "biome check --error-on-warnings",
+    "playtest": "devvit playtest",
+    "test": "npm run test:types && npm run lint && npm run test:unit && npm run build",
+    "test:types": "tsc --build",
+    "test:unit": "node --experimental-strip-types --no-warnings=ExperimentalWarning --test src/**/*.test.ts",
+    "publish": "npm run clean && npm run build && devvit publish",
+    "watch": "sh -c 'trap \"kill 0\" exit; npm run build:client -- --watch=forever& npm run build:server -- --watch=forever& wait' --"
+  },
+  "devDependencies": {
+    "@biomejs/biome": "2.6.6",
+    "@devvit/web": "0.15.3",
+    "@types/node": "24.19.2",
+    "devvit": "0.15.3",
+    "esbuild": "0.28.2",
+    "typescript": "7.0.2"
+  },
+  "engines": {
+    "node": ">=24.0.0"
+  }
+}

public/game.html

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+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <meta
+      name="viewport"
+      content="width=device-width, maximum-scale=1, minimum-scale=1, user-scalable=no"
+    >
+    <title>Game</title>
+    <link rel="modulepreload" href="game.js">
+    <style>
+    body {
+      margin: 0;
+      width: 100dvw;
+      height: 100dvh;
+      overflow: hidden;
+      display: grid;
+      place-items: center;
+    }
+    main {
+      display: grid;
+      gap: 1rem;
+      justify-items: center;
+    }
+    </style>
+  </head>
+  <body>
+    <main>
+      <div class="counter">
+        <button id="dec-btn" type="button">-</button>
+        <output id="counter">0</output>
+        <button id="inc-btn" type="button">+</button>
+      </div>
+    </main>
+    <script src="game.js" type="module"></script>
+  </body>
+</html>

public/splash.html

@@ -0,0 +1,31 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <title>Splash</title>
+    <link rel="modulepreload" href="splash.js">
+    <style>
+    body {
+      margin: 0;
+      width: 100dvw;
+      height: 100dvh;
+      overflow: hidden;
+      display: grid;
+      place-items: center;
+    }
+    main {
+      display: grid;
+      gap: 1rem;
+      justify-items: center;
+    }
+    </style>
+  </head>
+  <body>
+    <main>
+      <img src="/snoo.png" width="201" height="200" alt="Snoo">
+      <button id="start-btn" type="button">Start</button>
+    </main>
+    <script src="splash.js" type="module"></script>
+  </body>
+</html>

readme.md

@@ -0,0 +1,28 @@
+## Devvit Bare Template
+
+A practical [Devvit](https://developers.reddit.com/) app template with few dependencies. A little simpler at the expense of a little code.
+
+## Getting Started
+
+> Make sure you have Node 22 downloaded on your machine before running!
+
+1. Run `npm create devvit@latest --template=bare`
+2. Go through the installation wizard. You will need to create a Reddit account and connect it to Reddit Developers.
+
+## Commands
+
+- `npm run playtest [r/sub]`: watches changes, builds, uploads, and installs on Reddit. Accepts an optional subreddit.
+- `npm run build`: builds client and server, including esbuild metafiles.
+- `npm run clean`: removes build outputs.
+- `npm run test`: runs all tests.
+- `npm run format`: fixes lints and formatting.
+- `npm run lint`: checks lints and formatting.
+- `npm run publish`: cleans, builds, uploads, and files a new app review request.
+
+## Features
+
+- A plain Node.js server with front and backend typing.
+- Tests using the builtin Node.js test runner.
+- Promise misuse linter.
+- Formatter and bundler.
+- TypeScript project skeleton split by environment (frontend, backend, test, etc).

src/client/fetch.ts

@@ -0,0 +1,58 @@
+import {
+  Endpoint,
+  type GetCounterRsp,
+  type IncCounterReq,
+  type IncCounterRsp,
+} from '../shared/api.ts'
+
+export async function fetchGetCounter(): Promise<GetCounterRsp | undefined> {
+  let rsp
+  try {
+    rsp = await fetch(Endpoint.GetCounter, {
+      headers: {Accept: 'application/json'},
+    })
+  } catch (err) {
+    const msg = `HTTP error: ${err instanceof Error ? err.message : err}`
+    console.error(msg)
+    return
+  }
+
+  if (!rsp.ok) {
+    const text = await rsp.text().catch(() => '')
+    const err = `HTTP status ${rsp.status}: ${rsp.statusText}; ${text}`
+    console.error(err)
+    return
+  }
+
+  return (await rsp.json()) as GetCounterRsp
+}
+
+export async function fetchIncCounter(
+  amount: number,
+): Promise<IncCounterRsp | undefined> {
+  const req: IncCounterReq = {amount}
+  let rsp
+  try {
+    rsp = await fetch(Endpoint.IncCounter, {
+      headers: {
+        Accept: 'application/json',
+        'Content-Type': 'application/json',
+      },
+      method: 'POST',
+      body: JSON.stringify(req),
+    })
+  } catch (err) {
+    const msg = `HTTP error: ${err instanceof Error ? err.message : err}`
+    console.error(msg)
+    return
+  }
+
+  if (!rsp.ok) {
+    const text = await rsp.text().catch(() => '')
+    const err = `HTTP status ${rsp.status}: ${rsp.statusText}; ${text}`
+    console.error(err)
+    return
+  }
+
+  return (await rsp.json()) as IncCounterRsp
+}

src/client/game.ts

@@ -0,0 +1,23 @@
+import {fetchGetCounter, fetchIncCounter} from './fetch.ts'
+
+async function init(): Promise<void> {
+  const counter = document.getElementById('counter') as HTMLOutputElement
+  const incBtn = document.getElementById('inc-btn') as HTMLButtonElement
+  const decBtn = document.getElementById('dec-btn') as HTMLButtonElement
+
+  incBtn.addEventListener('click', () => void incCount(counter, 1))
+  decBtn.addEventListener('click', () => void incCount(counter, -1))
+
+  const rsp = await fetchGetCounter()
+  counter.value = rsp ? `${rsp.count}` : 'Error'
+}
+
+async function incCount(
+  counter: HTMLOutputElement,
+  amount: number,
+): Promise<void> {
+  const inc = await fetchIncCounter(amount)
+  counter.value = inc ? `${inc.count}` : 'Error'
+}
+
+void init()

src/client/splash.ts

@@ -0,0 +1,4 @@
+import {requestExpandedMode} from '@devvit/web/client'
+
+const startBtn = document.getElementById('start-btn') as HTMLButtonElement
+startBtn.addEventListener('click', ev => requestExpandedMode(ev, 'game'))

src/client/tsconfig.json

@@ -0,0 +1,9 @@
+// TypeScript config for all client code.
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "lib": ["DOM", "ES2023"],
+    "customConditions": ["browser"]
+  },
+  "references": [{"path": "../shared/"}]
+}

src/server/db.ts

@@ -0,0 +1,14 @@
+import {redis} from '@devvit/web/server'
+import type {T3} from '@devvit/web/shared'
+
+export async function dbGetCounter(t3: T3): Promise<number> {
+  return Number((await redis.get(counterKey(t3))) ?? 0)
+}
+
+export async function dbIncCounter(t3: T3, amount: number): Promise<number> {
+  return redis.incrBy(counterKey(t3), amount)
+}
+
+function counterKey(t3: T3): string {
+  return `count:${t3}`
+}

src/server/index.ts

@@ -0,0 +1,9 @@
+#!/usr/bin/env -S node --experimental-strip-types --no-warnings=ExperimentalWarning
+import {createServer, getServerPort} from '@devvit/web/server'
+import {onReq} from './server.ts'
+
+const server = createServer(onReq)
+const port: number = getServerPort()
+
+server.on('error', err => console.error(`server error; ${err.stack}`))
+server.listen(port, () => console.log(`http://localhost:${port}`))

src/server/server.test.ts

@@ -0,0 +1,93 @@
+import assert from 'node:assert/strict'
+import {createServer} from 'node:http'
+import type {AddressInfo, Server} from 'node:net'
+import {after, before, beforeEach, test} from 'node:test'
+import {type Context, redis, runWithContext} from '@devvit/web/server'
+import {
+  Endpoint,
+  type ErrorRsp,
+  type GetCounterRsp,
+  type IncCounterReq,
+  type IncCounterRsp,
+} from '../shared/api.ts'
+import {onReq} from './server.ts'
+
+let server: Server
+let serverURL: string
+const redisValues = new Map<string, number>()
+const redisGet = redis.get.bind(redis)
+const redisIncrBy = redis.incrBy.bind(redis)
+
+before(async () => {
+  redis.get = async key => `${redisValues.get(key) ?? 0}`
+  redis.incrBy = async (key, amount) => {
+    const value = (redisValues.get(key) ?? 0) + amount
+    redisValues.set(key, value)
+    return value
+  }
+
+  server = createServer(async (req, rsp) => {
+    await runWithContext(
+      {
+        appName: 'ninelands-game',
+        postId: 't3_123',
+        userId: 't2_123',
+        username: 'username',
+      } as unknown as Context,
+      () => onReq(req, rsp),
+    )
+  })
+  await new Promise<void>(resolve => {
+    server.listen(0, '127.0.0.1', () => resolve())
+  })
+  const info = server.address() as AddressInfo
+  serverURL = `http://127.0.0.1:${info.port}`
+})
+
+after(async () => {
+  redis.get = redisGet
+  redis.incrBy = redisIncrBy
+  if (!server.listening) return
+  await new Promise<void>((resolve, reject) => {
+    server.close(err => (err ? reject(err) : resolve()))
+  })
+})
+
+beforeEach(() => redisValues.clear())
+
+test('get counter', async () => {
+  const rsp = await fetch(`${serverURL}/${Endpoint.GetCounter}`)
+  assert.equal(rsp.status, 200)
+  assert.equal(rsp.headers.get('Content-Type'), 'application/json')
+  assert.deepEqual<GetCounterRsp>(await rsp.json(), {count: 0})
+})
+
+test('inc', async () => {
+  const req: IncCounterReq = {amount: 1}
+  const rsp = await fetch(`${serverURL}/${Endpoint.IncCounter}`, {
+    body: JSON.stringify(req),
+    headers: {'Content-Type': 'application/json'},
+    method: 'POST',
+  })
+  assert.equal(rsp.status, 200)
+  assert.equal(rsp.headers.get('Content-Type'), 'application/json')
+  assert.deepEqual<IncCounterRsp>(await rsp.json(), {count: 1})
+})
+
+test('wrong method', async () => {
+  const rsp = await fetch(`${serverURL}/${Endpoint.IncCounter}`)
+  assert.equal(rsp.status, 404)
+  assert.deepEqual<ErrorRsp>(await rsp.json(), {
+    error: 'not found',
+    status: 404,
+  })
+})
+
+test('404', async () => {
+  const rsp = await fetch(serverURL)
+  assert.equal(rsp.status, 404)
+  assert.deepEqual<ErrorRsp>(await rsp.json(), {
+    error: 'not found',
+    status: 404,
+  })
+})

src/server/server.ts

@@ -0,0 +1,118 @@
+import {once} from 'node:events'
+import type {IncomingMessage, ServerResponse} from 'node:http'
+import {context, reddit} from '@devvit/web/server'
+import type {
+  PartialJsonValue,
+  TriggerResponse,
+  UiResponse,
+} from '@devvit/web/shared'
+import {
+  Endpoint,
+  EndpointMethod,
+  type ErrorRsp,
+  type GetCounterRsp,
+  type IncCounterReq,
+  type IncCounterRsp,
+} from '../shared/api.ts'
+import {dbGetCounter, dbIncCounter} from './db.ts'
+
+type AnyRsp =
+  | GetCounterRsp
+  | IncCounterRsp
+  | UiResponse
+  | TriggerResponse
+  | ErrorRsp
+
+export async function onReq(
+  reqMsg: IncomingMessage,
+  rspMsg: ServerResponse,
+): Promise<void> {
+  try {
+    await route(reqMsg, rspMsg)
+  } catch (err) {
+    const msg = `server error; ${err instanceof Error ? err.stack : err}`
+    console.error(msg)
+    writeJson<ErrorRsp>(500, {error: msg, status: 500}, rspMsg)
+  }
+}
+
+async function route(
+  reqMsg: IncomingMessage,
+  rspMsg: ServerResponse,
+): Promise<void> {
+  const endpoint = reqMsg.url?.slice(1) as Endpoint
+  const method = EndpointMethod[endpoint]
+
+  let rsp: AnyRsp
+  if (method !== reqMsg.method) {
+    rsp = {error: 'not found', status: 404}
+  } else {
+    switch (endpoint) {
+      case Endpoint.GetCounter:
+        rsp = await routeGetCounter()
+        break
+      case Endpoint.IncCounter:
+        rsp = await routeInc(reqMsg)
+        break
+      case Endpoint.OnMenuNewPost:
+        rsp = await routeMenuNewPost()
+        break
+      case Endpoint.OnAppInstall:
+        rsp = await routeAppInstall()
+        break
+      default:
+        endpoint satisfies never
+        rsp = {error: 'not found', status: 404}
+        break
+    }
+  }
+
+  writeJson<PartialJsonValue>('status' in rsp ? rsp.status : 200, rsp, rspMsg)
+}
+
+async function routeGetCounter(): Promise<GetCounterRsp> {
+  const t3 = context.postId
+  if (!t3) throw Error('no t3')
+  return {count: await dbGetCounter(t3)}
+}
+
+async function routeInc(reqMsg: IncomingMessage): Promise<IncCounterRsp> {
+  const t3 = context.postId
+  if (!t3) throw Error('no t3')
+  const req = await readJson<IncCounterReq>(reqMsg)
+  return {count: await dbIncCounter(t3, req.amount)}
+}
+
+async function routeMenuNewPost(): Promise<UiResponse> {
+  const post = await reddit.submitCustomPost({title: context.appSlug})
+  return {
+    showToast: {text: `Post ${post.id} created.`, appearance: 'success'},
+    navigateTo: post.url,
+  }
+}
+
+async function routeAppInstall(): Promise<TriggerResponse> {
+  await reddit.submitCustomPost({title: context.appSlug})
+  return {}
+}
+
+async function readJson<T>(reqMsg: IncomingMessage): Promise<T> {
+  const chunks: Uint8Array[] = []
+  reqMsg.on('data', chunk => chunks.push(chunk))
+  await once(reqMsg, 'end')
+  return JSON.parse(`${Buffer.concat(chunks)}`)
+}
+
+function writeJson<T extends PartialJsonValue>(
+  status: number,
+  json: Readonly<T>,
+  rsp: ServerResponse,
+): void {
+  const body = JSON.stringify(json)
+  const len = Buffer.byteLength(body)
+  rsp.writeHead(status, {
+    'Content-Length': len,
+    'Content-Type': 'application/json',
+  })
+  rsp.end(body)
+}

src/server/tsconfig.json

@@ -0,0 +1,9 @@
+// TypeScript config for all server code.
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "types": ["node"],
+    "customConditions": ["server"]
+  },
+  "references": [{"path": "../shared/"}]
+}

src/shared/api.ts

@@ -0,0 +1,24 @@
+/** Generic error detail for all responses. */
+export type ErrorRsp = {error: string; status: number}
+
+/** The current counter state for this post. */
+export type GetCounterRsp = {count: number}
+
+/** Increment the post counter by a signed amount. */
+export type IncCounterReq = {amount: number}
+export type IncCounterRsp = {count: number}
+
+export type Endpoint = (typeof Endpoint)[keyof typeof Endpoint]
+export const Endpoint = {
+  GetCounter: 'api/counter',
+  IncCounter: 'api/counter/inc',
+  OnAppInstall: 'internal/on/app/install',
+  OnMenuNewPost: 'internal/on/menu/new-post',
+} as const
+
+export const EndpointMethod = {
+  [Endpoint.GetCounter]: 'GET',
+  [Endpoint.IncCounter]: 'POST',
+  [Endpoint.OnAppInstall]: 'POST',
+  [Endpoint.OnMenuNewPost]: 'POST',
+} as const satisfies {[endpoint: string]: 'GET' | 'POST'}

src/shared/tsconfig.json

@@ -0,0 +1,5 @@
+// TypeScript config for isomorphic code.
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {"lib": ["WebWorker", "ES2023"]}
+}

src/test/tsconfig.json

@@ -0,0 +1,15 @@
+// TypeScript config for test code.
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "lib": ["DOM", "ES2023"],
+    "types": ["node"]
+  },
+  "include": ["../**/*.test.*", "../**/test/", "../**/test/**/*.json"],
+  "exclude": ["${configDir}/node_modules/", "${configDir}/dist/"],
+  "references": [
+    {"path": "../client/"},
+    {"path": "../server/"},
+    {"path": "../shared/"}
+  ]
+}

tsconfig.base.json

@@ -0,0 +1,24 @@
+{
+  "compilerOptions": {
+    "composite": true,
+    "emitDeclarationOnly": true,
+    "target": "ES2023",
+    "moduleResolution": "Bundler",
+    "allowImportingTsExtensions": true,
+    "verbatimModuleSyntax": true,
+    "isolatedModules": true,
+    "noUncheckedIndexedAccess": true,
+    "erasableSyntaxOnly": true,
+    "rootDir": ".",
+    "outDir": "./dist/web/",
+    "skipLibCheck": true,
+    "lib": ["ES2023", "ESNext.Disposable"]
+  },
+  // Exclude colocated tests and test utils.
+  "exclude": [
+    "${configDir}/node_modules/",
+    "${configDir}/dist/",
+    "${configDir}/**/*.test.*",
+    "${configDir}/**/test/"
+  ]
+}

tsconfig.json

@@ -0,0 +1,10 @@
+{
+  // Only build references.
+  "files": [],
+  "references": [
+    {"path": "./src/client/"},
+    {"path": "./src/server/"},
+    {"path": "./src/shared/"},
+    {"path": "./src/test/"}
+  ]
+}