Software choices playbook

A playbook of default software choices for web apps, APIs and the services behind them. The other playbooks say what to build and how to check it on any stack. This one names the software we would pick when nothing forces another choice.

Every pick passes the same five tests in the first chapter. It has been in production use for years. It still gets regular releases. Many teams use it. AI coding tools know it well, because it fills their training data. A new developer can learn it from its own documentation in a day.

We pick open source whenever it passes the tests, and name a paid service only when no open source option does the job. Every pick carries a cost badge, from Open source to Paid. Each pick says when to choose something else. An existing system that works is a reason to keep it. Picks were checked against each project's own release pages in October 2026. Re-run the checks in the first chapter before you adopt any of them.

Chapters

1. How to choose

   Every pick here is proven, maintained, popular, known to AI tools and easy to learn. It also has an open licence or a way out.

   • Required 3
   • Recommended 5

2. Languages and runtimes

   Write TypeScript on a Node.js LTS line, or Python, with the package manager each one ships with. Learn SQL. Leave versions that are out of support.

   • Required 1
   • Recommended 5
   • Avoid 2

3. Web frameworks

   Our picks for the front end, the build, the server and the checks at the edge of your app. Each passes the five tests, with dates and numbers.

   • Required 1
   • Recommended 6
   • Optional 1
   • Avoid 2

4. Databases and storage

   We pick PostgreSQL and SQLite for data, Redis or Valkey for caches and jobs, an open ORM, Postgres search, and SeaweedFS for files.

   • Recommended 8
   • Avoid 2

5. Testing and code quality

   Our picks for test runners, browser and accessibility tests, linters, formatters, type checkers and the bot that keeps dependencies up to date.

   • Recommended 9
   • Avoid 1

6. Delivery and infrastructure

   Our picks for code hosting, CI, containers, infrastructure code, servers, proxies, certificates, DNS and secrets, each checked against the five tests.

   • Recommended 9
   • Avoid 1

7. Operations tools

   The tools we pick to watch a live app. Traces, metrics, dashboards, logs, errors, uptime checks, paging and Postgres backups.

   • Recommended 8
   • Optional 1
   • Avoid 1

8. Product services

   Our picks for payments, email sending, sign-in, push, text messages and analytics. Each comes with its evidence and a way to leave.

   • Recommended 7
   • Optional 1
   • Avoid 2

9. AI software

   AI software is young, and most of it fails the five-year test. Build on the boring layer of official SDKs, JSON Schema, PostgreSQL and your test runner.

   • Recommended 7
   • Optional 1

All 84 rules on one page

Related playbooks

• Setting up the project

  In the AI development playbook. Write the chosen software and its versions into the agent's instructions file, so it never guesses.

• Supply chain and setup

  In the Security testing playbook. Every package you pick becomes code you run. Lock, audit and review it before it ships.

• Documentation

  In the Engineering playbook. Record each choice and its exceptions as a decision record, so the next developer knows why.

• Infrastructure as code

  In the Infrastructure playbook. Install the picked servers and services from code, so the stack can be rebuilt the same way.