---
title: "Mario Zechner's Pi Lets Developers Build and Extend Their Own Coding Agent"
subtitle: "Pi is a minimal, aggressively extensible coding agent harness with unified access to 15+ LLM providers, tree-structured sessions, and self-modifying customization."
url: "https://alphasignal.ai/news/mario-zechner-s-pi-lets-developers-build-and-extend-their-own-coding-agent"
author: "AlphaSignal Newsroom"
author_url: "https://alphasignal.ai/editorial-team"
company: "AlphaSignal"
company_url: "https://alphasignal.ai/company/alphasignal"
published: "2026-05-06T23:04:51.000Z"
updated: "2026-08-22T16:28:47.643Z"
type: "Repo"
topics:
  - "Agents"
  - "Open Source"
subtopics:
  - "Agent Frameworks"
  - "Code Agents"
  - "Tool Use"
upvotes: 29
source_url: "https://github.com/badlogic/pi-mono"
comments: 0
truncated: true
---

# Mario Zechner's Pi Lets Developers Build and Extend Their Own Coding Agent

> Pi is a minimal, aggressively extensible coding agent harness with unified access to 15+ LLM providers, tree-structured sessions, and self-modifying customization.

Most coding agents ship as sealed products with baked-in opinions about sub-agents, plan mode, permission popups, and MCP. [Pi](https://github.com/earendil-works/pi), the agent harness formerly published as pi-mono by Mario Zechner (badlogic), takes the opposite bet: strip the harness down to primitives, then let the agent extend itself on the fly. The repo has crossed 95k stars and moved under the earendil-works organization with a dedicated site at [pi.dev](https://pi.dev).

The landing page sums up the philosophy: there are many agent harnesses, but this one is yours. Rather than shipping features, Pi ships primitives and hands you the tools to bolt on whatever behavior you actually need.

## What is actually in the box

Pi is a TypeScript monorepo split into a handful of packages you can adopt independently:

* **@earendil-works/pi-coding-agent**: the interactive coding agent CLI, installable via `curl`, npm, pnpm, or bun
* **@earendil-works/pi-agent-core**: the agent runtime with tool calling and state management
* **@earendil-works/pi-ai**: a unified multi-provider LLM API covering Anthropic, OpenAI, Google, and others
* **@earendil-works/pi-tui**: a terminal UI library with differential rendering
* **@earendil-works/pi-telemetry**: vendor-neutral telemetry contracts and typed schemas

Installing the CLI is a one-liner: `curl -fsSL https://pi.dev/install.sh | sh`. The project is MIT licensed and the coding agent is on npm as

_Preview only. Full text requires an AlphaSignal Pro account._

## Sources

- [earendil-works/pi on GitHub](https://github.com/earendil-works/pi)
- [Pi Coding Agent official site](https://pi.dev)
- [@earendil-works/pi-coding-agent on npm](https://www.npmjs.com/package/@earendil-works/pi-coding-agent)