Initial GameCult Bifrost Reddit bridge

.github/dependabot.yml

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+# 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"]
+    groups:
+      devvit:
+        patterns:
+          - "devvit"
+          - "@devvit/*"

.gitignore

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+node_modules
+.DS_Store
+dist
+.env
+public/*.js
+public/*.js.map
+devvit-playtest*.log

.npmrc

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+engine-strict=true

.nvmrc

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+22.6.0

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.

README.md

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+# GameCult Bifrost Reddit Bridge
+
+Devvit app for the Reddit-side actuator of Bifrost public transport.
+
+Bifrost owns governed GameCult crossings. This app gives Bifrost a Reddit-native
+body that can create subreddit posts and comments through Devvit, then return
+receipt-shaped JSON for the canonical Bifrost topic/comment store.
+
+## Authority
+
+- Owner: Bifrost.
+- Provider body: Reddit Devvit app `GameCult-Bifrost`.
+- Current app directory: `E:\Projects\gamecult-bifrost`.
+- Canonical discussion/approval: Bifrost governance topics.
+- Public action: Reddit posts and comments executed as the Devvit app account.
+- Receipt: `bifrost.reddit.receipt` JSON returned by the bridge endpoint.
+
+Personas should not call Reddit directly. They create Bifrost-governed intents;
+Bifrost routes authorized Reddit crossings through this app and records the
+permalink receipt back on the canonical topic.
+
+## Endpoints
+
+- `GET /api/health`
+- `POST /internal/bifrost/reddit-post`
+- `POST /internal/bifrost/reddit-comment`
+- `POST /internal/menu/post-create`
+- `POST /internal/on-app-install`
+
+Set `BIFROST_REDDIT_BRIDGE_SECRET` to require callers to send
+`x-bifrost-bridge-secret`. The secret check is deliberately small because
+Heimdall should own long-term credential custody and capability claims.
+
+### Reddit Post Request
+
+```json
+{
+  "actor": "nibu",
+  "source": "bifrost-topic:topic_...",
+  "subredditName": "GameCult",
+  "title": "Thread title",
+  "text": "Markdown body",
+  "idempotencyKey": "optional stable key"
+}
+```
+
+### Reddit Comment Request
+
+```json
+{
+  "actor": "nibu",
+  "source": "bifrost-topic-comment:comment_...",
+  "parentId": "t3_...",
+  "text": "Markdown body",
+  "idempotencyKey": "optional stable key"
+}
+```
+
+## Commands
+
+```powershell
+npm run type-check
+npm run build
+npm run dev
+npm run deploy
+```
+
+`npm run dev` starts a Reddit playtest session. `npm run deploy` builds and
+uploads a new app version.
+
+## Next Cut
+
+Wire the main `E:\Projects\Bifrost` bridge tooling to enqueue or invoke these
+Reddit actions from canonical governance topic comments, then store the returned
+`bifrost.reddit.receipt` on the topic as the public proof.

devvit.json

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+{
+  "$schema": "https://developers.reddit.com/schema/config-file.v1.json",
+  "name": "gamecult-bifrost",
+  "post": {
+    "dir": "public",
+    "entrypoints": {
+      "default": {
+        "inline": true,
+        "entry": "splash.html"
+      },
+      "game": {
+        "entry": "game.html"
+      }
+    }
+  },
+  "server": {
+    "dir": "dist/server",
+    "entry": "index.js"
+  },
+  "menu": {
+    "items": [
+      {
+        "label": "Create Bifrost bridge hub",
+        "description": "Create a Bifrost-owned Reddit bridge status post",
+        "location": "subreddit",
+        "forUserType": "moderator",
+        "endpoint": "/internal/menu/post-create"
+      }
+    ]
+  },
+  "triggers": {
+    "onAppInstall": "/internal/on-app-install"
+  },
+  "scripts": {
+    "dev": "node --experimental-strip-types ./tools/build.ts --watch",
+    "build": "node --experimental-strip-types ./tools/build.ts --minify"
+  },
+  "dev": {
+    "subreddit": "gamecult_bifrost_dev"
+  }
+}

package.json

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+{
+  "private": true,
+  "name": "gamecult-bifrost",
+  "version": "0.0.0",
+  "license": "BSD-3-Clause",
+  "type": "module",
+  "scripts": {
+    "build": "node --experimental-strip-types ./tools/build.ts --minify",
+    "deploy": "npm run build && devvit upload",
+    "dev": "devvit playtest",
+    "login": "devvit login",
+    "launch": "npm run build && npm run deploy && devvit publish",
+    "type-check": "tsc --build"
+  },
+  "engines": {
+    "node": ">=22.6.0"
+  },
+  "dependencies": {
+    "@devvit/web": "0.13.3",
+    "devvit": "0.13.3"
+  },
+  "devDependencies": {
+    "@types/node": "22.19.19",
+    "typescript": "6.0.3",
+    "esbuild": "0.28.0"
+  }
+}

public/game.css

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+* {
+  box-sizing: border-box;
+  margin: 0;
+  padding: 0;
+  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
+    Arial, sans-serif;
+}
+
+.app {
+  align-items: center;
+  background: #f7f3ea;
+  color: #171717;
+  display: flex;
+  min-height: 100vh;
+  justify-content: center;
+  padding: 24px;
+}
+
+.content {
+  display: grid;
+  gap: 14px;
+  max-width: 560px;
+  text-align: left;
+  width: min(100%, 560px);
+}
+
+.eyebrow {
+  color: #8a2f1b;
+  font-size: 0.78rem;
+  font-weight: 700;
+  letter-spacing: 0;
+  text-transform: uppercase;
+}
+
+.title {
+  font-size: 2rem;
+  line-height: 1.1;
+}
+
+.description {
+  color: #24513a;
+  font-size: 1rem;
+  font-weight: 650;
+  line-height: 1.45;
+}
+
+.ledger {
+  border-left: 3px solid #1c3f5f;
+  color: #3d3a35;
+  display: grid;
+  font-size: 0.92rem;
+  gap: 8px;
+  line-height: 1.35;
+  padding-left: 14px;
+}
+
+.footer {
+  bottom: 16px;
+  position: fixed;
+}
+
+.text-link {
+  background: transparent;
+  border: 0;
+  color: #1c3f5f;
+  cursor: pointer;
+  font-size: 0.82rem;
+  text-decoration: underline;
+}

public/game.html

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+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <link rel="stylesheet" type="text/css" href="game.css" />
+    <meta charset="UTF-8" />
+    <meta
+      name="viewport"
+      content="initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, width=device-width, height=device-height, user-scalable=0"
+    />
+    <title>Bifrost Reddit Bridge</title>
+  </head>
+  <body class="app">
+    <main class="content">
+      <p class="eyebrow">GameCult Bifrost</p>
+      <h1 class="title">Reddit bridge status</h1>
+      <p class="description" id="bridge-status">Checking bridge actuator...</p>
+      <section class="ledger">
+        <p>Owner: Bifrost</p>
+        <p>Actions: reddit-post, reddit-comment</p>
+        <p>Receipts: returned to canonical Bifrost topics</p>
+      </section>
+    </main>
+    <footer class="footer">
+      <button class="text-link" id="docs-link">Devvit docs</button>
+    </footer>
+    <script type="module" src="game.js" defer></script>
+  </body>
+</html>

public/splash.css

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+* {
+  box-sizing: border-box;
+  margin: 0;
+  padding: 0;
+  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
+    Arial, sans-serif;
+}
+
+.app {
+  align-items: center;
+  background: #f7f3ea;
+  color: #171717;
+  display: flex;
+  min-height: 100vh;
+  justify-content: center;
+  padding: 24px;
+}
+
+.content {
+  display: grid;
+  gap: 14px;
+  max-width: 520px;
+  text-align: center;
+}
+
+.eyebrow {
+  color: #8a2f1b;
+  font-size: 0.78rem;
+  font-weight: 700;
+  letter-spacing: 0;
+  text-transform: uppercase;
+}
+
+.title {
+  font-size: 2rem;
+  line-height: 1.1;
+}
+
+.description {
+  color: #4c4a45;
+  font-size: 1rem;
+  line-height: 1.45;
+}
+
+.open-button {
+  background: #1c3f5f;
+  border: 0;
+  border-radius: 6px;
+  color: #ffffff;
+  cursor: pointer;
+  font-size: 0.95rem;
+  justify-self: center;
+  min-height: 36px;
+  padding: 8px 16px;
+}
+
+.footer {
+  bottom: 16px;
+  position: fixed;
+}
+
+.text-link {
+  background: transparent;
+  border: 0;
+  color: #1c3f5f;
+  cursor: pointer;
+  font-size: 0.82rem;
+  text-decoration: underline;
+}

public/splash.html

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+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <link rel="stylesheet" type="text/css" href="splash.css" />
+    <meta charset="UTF-8" />
+    <meta
+      name="viewport"
+      content="initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, width=device-width, height=device-height, user-scalable=0"
+    />
+    <title>Bifrost Reddit Bridge</title>
+  </head>
+  <body class="app">
+    <main class="content">
+      <p class="eyebrow">GameCult Bifrost</p>
+      <h1 class="title">Reddit bridge actuator</h1>
+      <p class="description">
+        Governed posts and comments originate in Bifrost topics, then land here
+        with receipts.
+      </p>
+      <button class="open-button" id="open-button">Open status</button>
+    </main>
+    <footer class="footer">
+      <button class="text-link" id="docs-link">Devvit docs</button>
+    </footer>
+    <script type="module" src="splash.js" defer></script>
+  </body>
+</html>

src/client/game.ts

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+import { navigateTo } from "@devvit/web/client";
+import { ApiEndpoint, type HealthResponse } from "../shared/api.ts";
+
+const statusElement = document.getElementById("bridge-status");
+
+document.getElementById("docs-link")?.addEventListener("click", () => {
+  navigateTo("https://developers.reddit.com/docs");
+});
+
+async function refreshStatus(): Promise<void> {
+  if (!statusElement) {
+    return;
+  }
+
+  try {
+    const response = await fetch(ApiEndpoint.Health);
+    const data = (await response.json()) as HealthResponse;
+    statusElement.textContent =
+      data.status === "ok" ? "Bridge actuator online" : "Bridge status unknown";
+  } catch (error) {
+    console.error("Unable to read bridge status", error);
+    statusElement.textContent = "Bridge status unavailable";
+  }
+}
+
+void refreshStatus();

src/client/splash.ts

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+import { navigateTo, requestExpandedMode } from "@devvit/web/client";
+
+document.getElementById("open-button")?.addEventListener("click", (event) => {
+  requestExpandedMode(event, "game");
+});
+
+document.getElementById("docs-link")?.addEventListener("click", () => {
+  navigateTo("https://developers.reddit.com/docs");
+});

src/server/index.ts

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+import { createServer, getServerPort } from "@devvit/web/server";
+import { serverOnRequest } from "./server.ts";
+
+const server = createServer(serverOnRequest);
+const port: number = getServerPort();
+
+server.on("error", (err) => console.error(`server error; ${err.stack}`));
+server.listen(port);

src/server/server.ts

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+import type { IncomingMessage, ServerResponse } from "node:http";
+import { context, reddit } from "@devvit/web/server";
+import type {
+  PartialJsonValue,
+  TriggerResponse,
+  UiResponse,
+} from "@devvit/web/shared";
+import {
+  ApiEndpoint,
+  type BridgeCommentRequest,
+  type BridgePostRequest,
+  type BridgeReceipt,
+  type HealthResponse,
+} from "../shared/api.ts";
+import { once } from "node:events";
+
+export async function serverOnRequest(
+  req: IncomingMessage,
+  rsp: ServerResponse,
+): Promise<void> {
+  try {
+    await onRequest(req, rsp);
+  } catch (err) {
+    if (err instanceof BridgeError) {
+      writeJSON<ErrorResponse>(
+        err.status,
+        { error: err.message, status: err.status },
+        rsp,
+      );
+      return;
+    }
+
+    const msg = `server error; ${err instanceof Error ? err.stack : err}`;
+    console.error(msg);
+    writeJSON<ErrorResponse>(500, { error: msg, status: 500 }, rsp);
+  }
+}
+
+async function onRequest(
+  req: IncomingMessage,
+  rsp: ServerResponse,
+): Promise<void> {
+  const endpoint = getEndpoint(req.url);
+  if (!endpoint) {
+    writeJSON<ErrorResponse>(404, { error: "not found", status: 404 }, rsp);
+    return;
+  }
+
+  let body: BridgeReceipt | HealthResponse | UiResponse | TriggerResponse;
+  switch (endpoint) {
+    case ApiEndpoint.Health:
+      body = { type: "health", app: "gamecult-bifrost", status: "ok" };
+      break;
+    case ApiEndpoint.BridgePost:
+      assertBridgeSecret(req);
+      body = await onBridgePost(req);
+      break;
+    case ApiEndpoint.BridgeComment:
+      assertBridgeSecret(req);
+      body = await onBridgeComment(req);
+      break;
+    case ApiEndpoint.OnPostCreate:
+      body = await onMenuNewPost();
+      break;
+    case ApiEndpoint.OnAppInstall:
+      body = await onAppInstall();
+      break;
+    default:
+      endpoint satisfies never;
+      writeJSON<ErrorResponse>(404, { error: "not found", status: 404 }, rsp);
+      return;
+  }
+
+  writeJSON<PartialJsonValue>(200, body, rsp);
+}
+
+type ErrorResponse = {
+  error: string;
+  status: number;
+};
+
+async function onBridgePost(req: IncomingMessage): Promise<BridgeReceipt> {
+  const request = validatePostRequest(await readJSON<BridgePostRequest>(req));
+  const post = await reddit.submitPost({
+    subredditName: request.subredditName,
+    title: request.title,
+    text: renderGovernedBody(request.text, request),
+    sendreplies: false,
+    runAs: "APP",
+  });
+
+  return {
+    type: "bifrost.reddit.receipt",
+    action: "reddit-post",
+    actor: request.actor,
+    source: request.source,
+    target: `r/${request.subredditName}`,
+    redditId: post.id,
+    url: post.url || redditPermalink(post.permalink),
+    createdAt: new Date().toISOString(),
+  };
+}
+
+async function onBridgeComment(req: IncomingMessage): Promise<BridgeReceipt> {
+  const request = validateCommentRequest(
+    await readJSON<BridgeCommentRequest>(req),
+  );
+  const comment = await reddit.submitComment({
+    id: normalizeThingId(request.parentId),
+    text: renderGovernedBody(request.text, request),
+    runAs: "APP",
+  });
+
+  return {
+    type: "bifrost.reddit.receipt",
+    action: "reddit-comment",
+    actor: request.actor,
+    source: request.source,
+    target: request.parentId,
+    redditId: comment.id,
+    url: comment.url || redditPermalink(comment.permalink),
+    createdAt: new Date().toISOString(),
+  };
+}
+
+async function onMenuNewPost(): Promise<UiResponse> {
+  const subreddit = await reddit.getCurrentSubreddit();
+  const post = await reddit.submitCustomPost({
+    subredditName: subreddit.name,
+    title: "Bifrost bridge intake",
+    textFallback: {
+      text:
+        "Bifrost owns governed GameCult crossings into Reddit. " +
+        "Canonical proposals, approvals, and receipts remain in Bifrost.",
+    },
+    postData: {
+      kind: "gamecult-bifrost-bridge-hub",
+      createdBy: context.username ?? "unknown",
+    },
+  });
+
+  return {
+    showToast: { text: `Bridge hub ${post.id} created.`, appearance: "success" },
+    navigateTo: post.url || redditPermalink(post.permalink),
+  };
+}
+
+async function onAppInstall(): Promise<TriggerResponse> {
+  const subreddit = await reddit.getCurrentSubreddit();
+  await reddit.submitCustomPost({
+    subredditName: subreddit.name,
+    title: "Bifrost bridge online",
+    textFallback: {
+      text:
+        "The GameCult Bifrost Reddit bridge is installed. " +
+        "Bridge actions must still originate from governed Bifrost topics.",
+    },
+    postData: {
+      kind: "gamecult-bifrost-install-receipt",
+    },
+  });
+
+  return {};
+}
+
+function getEndpoint(url: string | undefined): ApiEndpoint | undefined {
+  if (!url || url === "/") {
+    return undefined;
+  }
+
+  const pathname = new URL(url, "https://devvit.local").pathname;
+  return Object.values(ApiEndpoint).find((endpoint) => endpoint === pathname);
+}
+
+function assertBridgeSecret(req: IncomingMessage): void {
+  const expectedSecret = process.env.BIFROST_REDDIT_BRIDGE_SECRET;
+  if (!expectedSecret) {
+    return;
+  }
+
+  const actualSecret = req.headers["x-bifrost-bridge-secret"];
+  if (actualSecret !== expectedSecret) {
+    throw new BridgeError(401, "invalid bridge secret");
+  }
+}
+
+function validatePostRequest(request: BridgePostRequest): BridgePostRequest {
+  assertNonEmpty(request.actor, "actor");
+  assertNonEmpty(request.source, "source");
+  assertNonEmpty(request.subredditName, "subredditName");
+  assertNonEmpty(request.title, "title");
+  assertNonEmpty(request.text, "text");
+  return request;
+}
+
+function validateCommentRequest(
+  request: BridgeCommentRequest,
+): BridgeCommentRequest {
+  assertNonEmpty(request.actor, "actor");
+  assertNonEmpty(request.source, "source");
+  assertNonEmpty(request.parentId, "parentId");
+  assertNonEmpty(request.text, "text");
+  return request;
+}
+
+function assertNonEmpty(value: unknown, field: string): asserts value is string {
+  if (typeof value !== "string" || value.trim().length === 0) {
+    throw new BridgeError(400, `missing ${field}`);
+  }
+}
+
+function normalizeThingId(id: string): `t1_${string}` | `t3_${string}` {
+  if (id.startsWith("t1_") || id.startsWith("t3_")) {
+    return id as `t1_${string}` | `t3_${string}`;
+  }
+
+  throw new BridgeError(400, "parentId must be a t1_ comment or t3_ post id");
+}
+
+function renderGovernedBody(
+  body: string,
+  request: BridgePostRequest | BridgeCommentRequest,
+): string {
+  const idempotency = request.idempotencyKey
+    ? `\n\nBifrost idempotency: ${request.idempotencyKey}`
+    : "";
+
+  return `${body.trim()}\n\n---\nBifrost source: ${request.source}\nActor: ${request.actor}${idempotency}`;
+}
+
+function redditPermalink(permalink: string): string {
+  if (permalink.startsWith("http")) {
+    return permalink;
+  }
+
+  return `https://www.reddit.com${permalink}`;
+}
+
+function writeJSON<T extends PartialJsonValue>(
+  status: number,
+  json: Readonly<T>,
+  rsp: ServerResponse,
+): void {
+  const body = JSON.stringify(json);
+  const len = Buffer.byteLength(body);
+  rsp.writeHead(status, {
+    "Content-Length": len,
+    "Content-Type": "application/json",
+  });
+  rsp.end(body);
+}
+
+async function readJSON<T>(req: IncomingMessage): Promise<T> {
+  const chunks: Uint8Array[] = [];
+  req.on("data", (chunk) => chunks.push(chunk));
+  await once(req, "end");
+  return JSON.parse(`${Buffer.concat(chunks)}`);
+}
+
+class BridgeError extends Error {
+  readonly status: number;
+
+  constructor(status: number, message: string) {
+    super(message);
+    this.status = status;
+  }
+}

src/shared/api.ts

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+export const ApiEndpoint = {
+  Health: "/api/health",
+  BridgePost: "/internal/bifrost/reddit-post",
+  BridgeComment: "/internal/bifrost/reddit-comment",
+  OnPostCreate: "/internal/menu/post-create",
+  OnAppInstall: "/internal/on-app-install",
+} as const;
+
+export type ApiEndpoint = (typeof ApiEndpoint)[keyof typeof ApiEndpoint];
+
+export type HealthResponse = {
+  type: "health";
+  app: "gamecult-bifrost";
+  status: "ok";
+};
+
+export type BridgePostRequest = {
+  actor: string;
+  source: string;
+  subredditName: string;
+  title: string;
+  text: string;
+  idempotencyKey?: string;
+};
+
+export type BridgeCommentRequest = {
+  actor: string;
+  source: string;
+  parentId: string;
+  text: string;
+  idempotencyKey?: string;
+};
+
+export type BridgeReceipt = {
+  type: "bifrost.reddit.receipt";
+  action: "reddit-post" | "reddit-comment";
+  actor: string;
+  source: string;
+  target: string;
+  redditId: string;
+  url: string;
+  createdAt: string;
+};

tools/build.ts

@@ -0,0 +1,56 @@
+#!/usr/bin/env -S node --experimental-strip-types
+
+// Bundles sources to dist/ and public/.
+//
+// build.ts [--minify] [--watch]
+// --local  Run development server. Serve on http://localhost:1234 and reload on
+//          code change.
+// --minify    Minify output.
+// --watch     Automatically rebuild whenever an input changes.
+
+import fs from "node:fs";
+import type { BuildOptions } from "esbuild";
+import esbuild from "esbuild";
+
+const watch = process.argv.includes("--watch");
+
+const opts: BuildOptions = {
+  bundle: true,
+  logLevel: "info", // Print the port and build demarcations.
+  metafile: true,
+  sourcemap: "linked",
+  target: "es2023", // https://esbuild.github.io/content-types/#tsconfig-json
+};
+
+const clientOpts: BuildOptions = {
+  ...opts,
+  entryPoints: ["src/client/splash.ts", "src/client/game.ts"],
+  format: "esm",
+  outdir: "public",
+  platform: "browser",
+};
+const serverOpts: BuildOptions = {
+  ...opts,
+  entryPoints: ["src/server/index.ts"],
+  format: "cjs",
+  outdir: "dist/server",
+  platform: "node",
+};
+
+if (watch) {
+  const clientCtx = await esbuild.context(clientOpts);
+  const serverCtx = await esbuild.context(serverOpts);
+  await Promise.all([
+    watch ? clientCtx.watch() : undefined,
+    watch ? serverCtx.watch() : undefined,
+  ]);
+} else {
+  const [client, server] = await Promise.all([
+    esbuild.build(clientOpts),
+    esbuild.build(serverOpts),
+  ]);
+  if (client.metafile)
+    fs.writeFileSync("dist/client.meta.json", JSON.stringify(client.metafile));
+  if (server.metafile)
+    fs.writeFileSync("dist/server.meta.json", JSON.stringify(server.metafile));
+}

tools/tsconfig.base.json

@@ -0,0 +1,57 @@
+{
+  "$schema": "https://json.schemastore.org/tsconfig.json",
+  "compilerOptions": {
+    // Enable incremental builds.
+    "composite": true,
+
+    // Enable type-stripping.
+    "allowImportingTsExtensions": true,
+
+    // Only allow type-strippable syntax.
+    "erasableSyntaxOnly": true,
+
+    // Maximize type checking.
+    "allowUnreachableCode": false,
+    "allowUnusedLabels": false,
+    "forceConsistentCasingInFileNames": true,
+    "noImplicitOverride": true,
+    "noUncheckedIndexedAccess": true,
+    "noUncheckedSideEffectImports": true,
+    "noUnusedLocals": true,
+    "resolveJsonModule": true,
+    "strict": true,
+
+    // Projects add types needed.
+    "lib": ["ES2023"],
+    "types": [],
+
+    "isolatedDeclarations": true, // Require explicit types.
+
+    // Improve compatibility with compilers that aren't type system aware.
+    "isolatedModules": true,
+
+    "esModuleInterop": true, // Use ESM.
+
+    // Allow JSON type-checking and imports.
+    "module": "ESNext",
+    "moduleResolution": "Bundler",
+
+    "rewriteRelativeImportExtensions": true, // Rewrite .ts imports to .js.
+
+    // All subprojects output to dist/ relative the project root.
+    "outDir": "../dist",
+    "rootDir": "..",
+
+    // Assume library types are checked and compatible.
+    "skipLibCheck": true,
+    "skipDefaultLibCheck": true,
+
+    "sourceMap": true,
+    "declarationMap": true, // Map back to original sources, not .d.ts.
+
+    "target": "ES2023",
+
+    // Don't transform type-only imports.
+    "verbatimModuleSyntax": true
+  }
+}

tools/tsconfig.client.json

@@ -0,0 +1,17 @@
+{
+  "extends": "./tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "../dist/types/client",
+    "lib": ["DOM", "ES2023"],
+    "tsBuildInfoFile": "../dist/types/client/tsconfig.tsbuildinfo",
+    "customConditions": ["browser"],
+    "rootDir": "../src/client"
+  },
+  "include": ["../src/client/**/*"],
+  "exclude": ["../src/server/**/*"],
+  "references": [
+    {
+      "path": "./tsconfig.shared.json"
+    }
+  ]
+}

tools/tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "extends": "./tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "../dist/types/server",
+    "tsBuildInfoFile": "../dist/types/tools/tsconfig.tsbuildinfo",
+    "types": ["node"]
+  }
+}

tools/tsconfig.server.json

@@ -0,0 +1,16 @@
+{
+  "extends": "./tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "../dist/types/server",
+    "tsBuildInfoFile": "../dist/types/server/tsconfig.tsbuildinfo",
+    "customConditions": ["server"],
+    "types": ["node"],
+    "rootDir": "../src/server"
+  },
+  "include": ["../src/server/**/*"],
+  "references": [
+    {
+      "path": "./tsconfig.shared.json"
+    }
+  ]
+}

tools/tsconfig.shared.json

@@ -0,0 +1,10 @@
+{
+  "extends": "./tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "../dist/types/shared",
+    "tsBuildInfoFile": "../dist/types/shared/tsconfig.tsbuildinfo",
+    "rootDir": "../src/shared"
+  },
+  "include": ["../src/shared/**/*"],
+  "exclude": []
+}

tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "files": [],
+  "references": [
+    { "path": "./tools/tsconfig.client.json" },
+    { "path": "./tools/tsconfig.server.json" },
+    { "path": "./tools/tsconfig.shared.json" }
+  ]
+}