A local AI theater for roleplay, DMs, and dice rolls

What it does

Marinara Engine is a self-hosted TypeScript application that bundles AI chat, immersive roleplay, and AI Game Master sessions into one interface. It runs locally in a browser or as a mobile PWA, stores everything on your own disk, and connects to a wide range of LLM and image providers—from OpenAI and Anthropic to local sidecars and ComfyUI. You can import character cards from popular community hubs, branch conversations, and switch between Discord-style DMs, sprite-based roleplay scenes, and party-based game modes.

The interesting bit

Instead of bloating the base install with every feature, the engine ships with a lightweight core and offers 29 optional first-party agents—ranging from prose editors to UNO dealers—that you download à la carte and automatically update. That modular approach, plus built-in weather overlays, expression sprites, and a card browser that pulls from multiple roleplay repositories, suggests the authors are building a creative toolkit, not just another ChatGPT wrapper.

Key highlights

• Three distinct modes: Conversation (DMs), Roleplay (sprites/backgrounds/weather), and Game (AI GM with quests, combat, and party stats).
• Optional agent catalog with 29 downloadable packages (Writer, Tracker, Game, and Misc categories) that auto-update when online but work offline once installed.
• Imports character cards from Chub.ai, JannyAI, CharacterTavern, Pygmalion, Wyvern, and SillyTavern.
• AES-256 encrypted API keys at rest, local file-native storage, and no required user account.
• Broad provider support including OpenAI, Anthropic, Gemini, OpenRouter, local models, Draw Things on Apple Silicon, and multiple video-generation endpoints.

Caveats

• The project is alpha software; the README warns of rough edges, missing features, and breaking changes.
• Native mobile apps are still on the roadmap; current Android support uses a Termux bootstrap APK and iOS relies on PWA installation.

Verdict

Worth a look if you want a private, local alternative to cloud-hosted roleplay frontends and don’t mind living on an early release. If you need polished native mobile apps or enterprise stability, wait for a later release.