Lucas ZimmermannLZ

Uses

What I use.

The tools I open every day. Editor, AI workflow, default stack, infrastructure. Nobody paid me to list any of this.

Editor & terminal

VS Code

Default editor. Dark theme, minimal UI, no exotic setup — the config should survive a laptop swap in ten minutes.

ESLint + Prettier

Formatting and lint arguments are decided by machines so humans can argue about architecture instead.

Tailwind CSS IntelliSense

Non-negotiable once a project uses Tailwind; class strings without it are write-only.

GitLens + Error Lens

Blame context inline and errors where the eyes already are. Small tools, large minutes saved.

AI in the loop

AI tools are part of the daily workflow, but always inside guardrails — the same deterministic-first philosophy as the projects.

Claude Code

Primary coding agent for implementation work and refactors. Treated like a very fast junior: clear mandate in, reviewed diff out.

Codex CLI + Fencier

Agent runs are wrapped in my own guardrail tool — policy checks, scope verification and audit trails on every diff. Dogfooding as QA.

OpenAI API

The model layer inside products (Medbay, Georgie on this site). Constrained calls, schema-validated outputs, budget caps.

LangGraph

For agent systems where the control flow deserves to be a real graph instead of a prompt hoping for the best.

Default stack

The boring-on-purpose foundation most of my projects start from.

TypeScript everywhere

One language across frontend, backend and tooling. Type errors are the cheapest bugs you will ever fix.

Next.js + React

App Router, server components where they pay off. The framework carries routing, rendering and deployment concerns I refuse to own.

PostgreSQL

The default answer to storage questions. Row-level security, real constraints, and it will outlive every trendy alternative.

Zod

Every boundary — API input, model output, env vars — gets a schema. Untrusted data is a category, not an exception.

Infrastructure

Chosen with the allocator's rule: pay managed-service premiums to buy back founder-time, self-host only what differentiates.

Vercel

Hosting that scales to zero and deploys on push. The infra bill stays a rounding error until there is real usage.

Supabase

Managed Postgres with auth and row-level security included — an entire backend team's worth of undifferentiated work, rented.

Redis + BullMQ

For event-driven systems like CareLoop: deterministic job IDs, retries and queues that can be inspected when things go wrong.

Docker

For anything that must run the same on my machine, a client's server and CI. Not for cosplaying Google-scale ops.