Phase 0: Agents in Production · 35 hours · TypeScript / Bun (harness) · Python (eval scripts)

Capstone 01 — Terminal-Native Coding Agent

By 2026 the shape of a coding agent is settled.

Hiring signal: Can build capstone 01 end to end

Introduction

A TUI harness, a stateful plan, a sandboxed tool surface, a loop that plans, acts, observes, recovers. Claude Code, Cursor 3, and OpenCode all look the same from 50 feet. This capstone asks you to build one end to end — CLI in, pull request out — and measure it against mini-swe-agent and Live-SWE-agent on SWE-bench Pro. You will learn why the hard part is not the model call but the tool loop, the sandbox, and the cost ceiling on a 50-turn run.

Phases exercised: P0 · P5 · P7 · P10 · P11 · P13 · P14 · P15 · P17 · P18

Type: Capstone Languages: TypeScript / Bun (harness), Python (eval scripts) Prerequisites: Phase 11 (LLM engineering), Phase 13 (tools and protocols), Phase 14 (agents), Phase 15 (autonomous systems), Phase 17 (infrastructure) Time: 35 hours

Objective

Learning objectives

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You've read the first 2 sections. The rest of this lesson covers The Problem, The Concept, Build, Check Yourself, Key Terms & Next — plus a hands-on lab, quiz, and project artifact.

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