jev-arena
Real-time bot battles where you write a fighter's strategy in plain English and a System One model pilots it several times a second.
Overview
Jev Arena is a real-time bot-battle game in which each fighter is a short YAML file with a plain-English strategy and optional reflexes, such as shield when a heavy shot is incoming above a 0.7 threshold, plus a fallback action. There is no code, coordinates or if-statements. A System One model reads the game state and returns typed decisions several times a second, supplying the fighter's reflexes while the fight runs; the brain is swappable among Jev, LAYA, kev or any LLM.
The author's point is that chat LLMs react too slowly for real-time play, while Jev's quoted 70-500 ms response is fast enough. A public ladder runs on GitHub Actions and is joined by pull request, with Elo ratings published live. The README notes that a one-sentence fighter called Zen, with no reflexes, finished second of six, one Elo point behind the leader, while a carefully tuned sniper went 0-10. It is published on npm and MIT licensed.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Choice | What should this fighter do right now given its strategy and the game state?(inferred) | — |
| Yes / no | Is the reflex condition met (e.g. a heavy shot is incoming)? | yes · no |
How it works
- Write a fighter YAML with strategy, reflexes and fallback
- Game engine summarises state several times a second
- Model checks reflexes and picks an action
- Engine applies actions; ladder computes Elo
Strengths
- Strategy authored in plain English
- Swappable brains including open models
- Ladder joined via pull request
Caveats
- Game results show behaviour, not general accuracy
- Small ladder (six fighters)
Getting started
Install from npm (jev-arena) and play locally, or watch the ladder at https://eliot5566.github.io/jev-arena/.At a glance
- Type
- Project
- Status
- beta
- Language
- TypeScript
- Runtime
- Node game engine, GitHub Actions ladder
- Has code
- yes
- License
- MIT
Use cases and integrations
How curated lists describe it
That's the whole bot. No code, no coordinates, no if-statements.
logicrw/awesome-jev-projects
Frequently asked questions
How do I write a fighter?
A YAML file with a plain-English strategy, optional reflexes with thresholds, and a fallback action.
Which models can pilot fighters?
Jev, LAYA, kev or any LLM.
How do I join the ladder?
Submit a pull request with your fighter.
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