Blog / field notes
Building and testing software.
Practical notes on Pytest, AI engineering, team habits, legacy systems, and the work required to make software safe to change.
OpenAI Codex Tutorial: Free Full Course with Python
A free, 3-hour, project-based OpenAI Codex tutorial for Python developers. Build, test, deploy, and review a real app with Codex.
Pytest Hooks Tutorial: 5 Practical Examples for Python Tests
Learn where pytest hooks fit, when to choose a hook over a fixture, and how to customize collection, reporting, and test runs with working examples.
Python Unit Testing Best Practices: 10 pytest Rules That Scale
Write Python unit tests that survive refactoring. Use pytest to protect behavior, choose useful cases, control dependencies, and keep the suite fast.
Test-Driven Development in Python with pytest: A Practical Guide
Use pytest to practice red-green-refactor on a realistic inventory rule. Write each failing test first, add only enough code, and refactor safely.
GitHub Actions Python Testing: A Complete pytest CI Guide
Build a pytest workflow in GitHub Actions with dependency caching, multiple Python versions, branch coverage, reports, and a stable merge check.
How to Test a LangGraph Agent with pytest (Without API Calls)
Build a small tool-using LangGraph workflow and test its model, tool, and failure path with pytest-mock, without calling a live LLM or external service.
FastAPI Testing with Pytest: A Practical API Testing Tutorial
Build a small FastAPI endpoint, test its success and validation contracts with pytest and TestClient, and learn what a useful API test should prove.
Pytest for Beginners: Write and Run Your First Python Test
If you know how to write a Python function, you know enough to start testing. Build, run, and debug your first pytest test without creating a package.
AI Coding Agents: Production Reliability Matters
AI coding agents make implementation cheap, but reliable systems still require contracts, TDD, layered tests, disciplined reviews, and useful documentation. Here is a production-minded workflow you can apply with any agent.
How to Guide AI Coding Agents to Write Better pytest Tests
AI agents often test the line they changed instead of the behavior a unit owns. Add durable testing instructions, enforce a pytest coverage gate, and review generated tests against stable contracts.
How to Onboard a Python Team to Testing with Pytest
Learn how a 15-developer Python team used shared practice, legacy-code pinch points, and CI to turn pytest into an everyday engineering habit.