coding

Femtobot: 10MB Rust Telegram Bot vs 350MB Python

A developer compares building a Telegram bot in Rust versus Python, showing how the Rust version achieves a 10MB binary size compared to Python's 350MB

Someone got tired of “lightweight” chatbot frameworks still needing 350MB+ of Python dependencies, so they rewrote the concept in Rust.

The result is femtobot - a single 10MB binary that runs Telegram bots with local memory and tool execution. Perfect for old Raspberry Pis or cheap VPS instances where disk space actually matters.

Quick start:

Uses SQLite for memory, supports shell/filesystem/web tools via rig-core, and starts up nearly instantly. The code isn’t perfect Rust (built quickly with AI help), but it boots on hardware that would choke on a virtualenv.

Interesting alternative to Python stacks when running agents on constrained devices. Trades some ecosystem polish for actual resource efficiency.