https://github.com/c-ehrlich/micropolis
https://github.com/c-ehrlich/micropolis
Last synced: 3 months ago
JSON representation
- Host: GitHub
- URL: https://github.com/c-ehrlich/micropolis
- Owner: c-ehrlich
- License: gpl-3.0
- Created: 2026-02-03T05:36:54.000Z (5 months ago)
- Default Branch: main
- Last Pushed: 2026-02-18T12:16:25.000Z (4 months ago)
- Last Synced: 2026-04-04T04:53:54.022Z (3 months ago)
- Language: TypeScript
- Homepage: https://micropolis.vercel.app
- Size: 21.2 MB
- Stars: 24
- Watchers: 0
- Forks: 0
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- Agents: AGENTS.md
Awesome Lists containing this project
README
# Micropolis (TypeScript port with gpt-5.3-codex)
The SimCity (1989) codebase was open sourced by EA under the name "Micropolis" as part of the OLPC (One Laptop Per Child) project. It's a C codebase, but large parts of it were ported from Assembly.
I wanted to push how long I can run the current generation of LLMs unattended if they are working with a clear spec and verifiable tasks, so I decided to port it to TypeScript and make it run in the browser.
I used exclusively `gpt-5.3-codex` with thinking set to high. After 4 days of work (most of it just letting Codex run unattended), this is what I ended up with.
My main innovation was creating a harness that calls the C code and uses `fast-check` to assert that my code behaves the same as the source for arbitray input, allowing the model to work unattended until it reaches a complete solution.
Surprisingly this got a lot of attention on Twitter, including
- Garry Tan - https://x.com/garrytan/status/2021241956806922370
- Greg Brockman - https://x.com/gdb/status/2021272681237361027
- Sriram Krishnan - https://x.com/sriramk/status/2021268764923244550
So I decided to publish the codebase.
Originally my goal was to port the game and then make it multiplayer (humans and LLMs) as a fun/art project. I might still do that in the future, but I'll freeze this codebase as a reference. PRs likely won't be accepted.
## Requirements
- Node.js >= 24
- pnpm >= 10.28 (Corepack recommended)
## Getting started
```bash
corepack enable
pnpm install
pnpm dev
```
## Workspace layout
- `apps/web`: Vite + React app using TanStack Router (file-based routes live in `src/routes`)
- `packages`: Ports of the core Micropolis engine, tiles, harness, etc
## Common commands
```bash
pnpm dev
pnpm build
pnpm lint
pnpm typecheck
pnpm test
pnpm format
```
## Autonomous task orchestration
The repo includes a Codex-driven orchestrator at `scripts/auto-orchestrator.mjs`. I change it for each long-running task, so it just contains whatever made sense for the last iteration.
Inspect queue + drift:
```bash
pnpm auto:queue
pnpm auto:drift
```
Run unattended (default runtime cap: 24 hours):
```bash
pnpm auto:run -- --max-runtime-minutes 1440
```
Useful flags:
- `--once`: complete exactly one task and stop.
- `--dry-run`: plan/selection only; no git push or PR changes.
- `--streams `: run only specific stage stream ids (`stage-0` ... `stage-4`).
- `--no-tests`: remove `pnpm test` from `--checks` if present.
- `--max-retries-per-task `: retries before a task is marked blocked.
- `--model `: pass a specific model to `codex exec`.
The orchestrator stores state/logs in `.automation/`.
Create `.automation/STOP` to halt the loop after the current iteration.
## Turborepo remote caching
Remote caching is ready to wire up when you want it:
```bash
pnpm dlx turbo login
pnpm dlx turbo link
```
Then set `TURBO_TOKEN` and `TURBO_TEAM` in CI secrets.
## License
This project is a modified version of the Micropolis source released by Electronic Arts under the GNU General Public License v3 (or later). The full GPLv3 text is in [LICENSE](LICENSE). The original Micropolis license notice and additional terms (including trademark restrictions) are preserved in [ref/micropolis/README](ref/micropolis/README).