# phoboslab/underrun

Twin stick shooter game in 13kb of JavaScript/WebGL

Repository: https://github.com/phoboslab/underrun
Canonical: https://ross.abutalabs.com/products/underrun
Language: JavaScript
License: MIT
License Family: permissive
Last push: 2022-01-26T19:29:41+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 2912, "days_push": 1680, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1108, forks 114 (observed 2026-08-28T04:03:37.064748+00:00)

## What it is
Underrun is a twin-stick shooter game written in 13kb of JavaScript using WebGL, created as an entry for the 2018 js13k competition. It is a complete, playable browser game released under the MIT license.

## Use cases
- play a small browser-based twin-stick shooter game
- study how a full game fits into 13kb of JavaScript
- learn WebGL game rendering techniques
- explore js13k competition entries
- use as a starting point for tiny browser games

## When to choose
- you want a lightweight game that runs directly in the browser
- you are studying size-constrained (js13k) game development
- you want a compact WebGL code example

## When to avoid
- you need a full-featured game engine or extensible game framework
- you need long-term maintained or updated game code
- you need a native desktop or mobile game

## Facets
- artifact type: application
- maturity: maintenance
- function: game-engine, graphics
- domain: gaming-tools, web-development
- platform: browser
- tags: js13k, twin-stick-shooter, webgl, size-coding, javascript-game, game-development, web-server

## Member repositories
- phoboslab/underrun (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:37.064748+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T06:43:51.116207+00:00, confidence not recorded.
  - readme: https://github.com/phoboslab/underrun (fetched 2026-08-28T04:03:37.064748+00:00, sha 35599b214cfb)
- Data as of 2026-08-30T08:39:29.467469+00:00.