How Do Startup CTOs Build a Software Factory with AI Agents?
For Startup CTOs and technical co-founders · Based on Lou Bichard Software Factory Primitives Framework
// TL;DR
Startup CTOs building a software factory for a single product repo should use the Software Factory Primitives Framework to move beyond parallel-agent assistance. The Swarm pattern — one intent fanning out to sub-agents that funnel results into a single PR — fits single-repo work. Decompose your SDLC into gated micro-steps, build a CLI gateway for agent coordination, and apply Harness Engineering to encode process knowledge into the repo so agents improve with every run.
Why Does Running Multiple AI Coding Agents Still Feel Like Babysitting?
You have Claude Code or Cursor running. Maybe multiple instances. But you are still the orchestrator — reviewing each output, deciding what happens next, copy-pasting context between sessions. You are running parallel agents, not a software factory.
A software factory requires incrementally removing you from the loop. Work flows from spec to production autonomously, with you on-the-loop (able to see state and intervene) but not in-the-loop (not driving each step). The difference is structural, not just about adding more agents.
The Software Factory Primitives Framework diagnoses exactly what is missing. Audit your four primitives: Runtime (where agents run — probably solved), Orchestration (can you scale agents — probably solved), Triggers (do events start agents — partially solved), Coordination (can agents gate progress and hand off — almost certainly missing).
How Do I Go From Spec to Reviewable PR Without Constant Intervention?
The Swarm pattern fits single-repo work: one intent (a spec) fans out to multiple sub-agents that funnel results back into a single PR. But swarm without coordination is chaos.
Decompose your SDLC into micro-steps:
Plan micro-steps:
1. Parse the spec
2. Identify affected components
3. Generate task list with dependencies
4. Validate task list against codebase structure — gate
Build micro-steps:
5. Scaffold new files
6. Implement component A
7. Implement component B
8. Integration pass — gate: code compiles
Test micro-steps:
9. Write unit tests for component A
10. Write unit tests for component B
11. Run all tests — gate: tests pass, coverage threshold met
12. Edge case tests — gate
Review micro-steps:
13. Self-review against spec
14. Raise PR with structured description
Build a CLI gateway — a tool your agent can invoke as a tool call: "Have I completed micro-step 8? May I proceed?" The gateway checks machine-verifiable conditions (compiles, tests pass, files exist) and returns a proceed/halt signal. This prevents agents from claiming completion when they have skipped steps.
What Is Context Rot and Why Does It Kill Long-Running Agent Tasks?
Context rot is the degradation of agent performance as the context window fills. On a 30-minute task, the agent starts strong but gradually loses track of the spec, skips steps, and produces lower-quality output. This is the hardest problem in building a software factory.
The fix is Harness Engineering: after each failed run, identify exactly which micro-step the agent drifted at. Encode the fix back into the repository:
- agents.md: process rules, coding standards, SDLC step sequence
- Context files: architecture decisions, component relationships, spec details
- Unit tests: machine-checkable verification that catches agent drift
The repository becomes smarter over time. Each Harness Engineering cycle makes agents more reliable without you needing to babysit them.
How Do I Know When to Intervene vs When to Let the Agent Continue?
Design your oversight UX to show where to intervene, not everything that is happening. Your coordination layer should surface:
- Which micro-step each sub-agent is on
- Which gates have passed or failed
- Where an agent is blocked or looping
Do not pipe all agent activity through GitHub PRs or Linear tickets. You will drown in noise. Build a lightweight dashboard or CLI status command that shows coordination state.
Next step: Pick one feature spec and decompose its SDLC into micro-steps. Build a simple CLI gateway that checks one gate (tests pass) before the agent proceeds. Run one Harness Engineering cycle. This gives you the foundation to expand incrementally toward a true software factory.
// FREQUENTLY ASKED QUESTIONS
Can a startup build a software factory with Claude Code or Cursor?
Yes. Claude Code or Cursor serves as your agent runtime — the first of the four primitives. You still need to build the coordination layer on top: decompose your SDLC into micro-steps, implement a CLI gateway for gate checks, and apply Harness Engineering. The framework is agent-tool agnostic and works with any coding agent as the execution layer.
How much engineering effort does it take to build a coordination layer for a single repo?
Start small. A CLI gateway that checks one gate (tests pass before PR creation) can be built in a day. Micro-step decomposition for one SDLC stage takes a few hours. Harness Engineering is ongoing — each failed agent run reveals what to encode next. The framework is designed for incremental adoption, not a big-bang implementation.
What's the fastest way to reduce how much I babysit coding agents?
Decompose your most common task into micro-steps, add machine-checkable gates at each boundary, and encode your most frequent corrections into agents.md. This prevents the two biggest time sinks: agents skipping steps (caught by gates) and agents making the same mistakes repeatedly (fixed by Harness Engineering). Each cycle reduces your intervention surface.