Cyréna – An offline-first AI engineering assistant with PlatformIO support
Hi all,
I’ve been working on an open source AI assistant called Cyréna, designed to work alongside your IDE rather than inside it. I wanted to share it here because it has first-class PlatformIO support.
Why it’s different
Most AI coding assistants are general purpose and have little awareness of embedded development or the conventions of tools like PlatformIO. Cyréna is built specifically around structured project workflows.
Cyréna enforces a strict structure. The model cannot invent folders or place files arbitrarily. For PlatformIO projects, it understands the src and include folder conventions and works within them. It also indexes the lib folder as read-only and in the case of espidf framework, it indexes managed_components and components folders as well and adds sdkconfig files as read-only.
Offline first
Cyréna is designed to run with local models via Ollama. It targets models in the ~20B class so you don’t need massive hardware. OpenAI is also supported if you prefer it.
What it supports
- PlatformIO projects — Arduino and ESP-IDF frameworks
- Arduino IDE projects
- .NET projects (Blazor, MVC, Class Libraries)
- General chat mode for when you just want to ask questions
Where to get it
This is an early alpha. I use it daily and would appreciate feedback and improvement suggestions. Expect rough edges.