THE LAB / PRACTICAL ENGINEERING

From “it works”
to “I understand it”.

Small tools for better engineering conversations. Start here, discover the gaps, and decide what deserves a closer look.

PRE-FLIGHT

Before you ship that AI-built app.

A working interface tells you very little about what happens when the wrong user, a failed request, or a broken deployment arrives. Work through these six checks with evidence.

Your answers stay in this page. They aren’t sent anywhere or saved after you leave.

Checks you have verifiedUsers can only access their own data.Try another user’s record or organisation ID. Check permissions on the server, including APIs and downloads.Secrets stay out of the browser and repository.Check API keys, connection strings, generated code, logs, and repository history. Revoke and replace anything that has leaked.Unexpected inputs fail safely.Test empty values, invalid IDs, oversized input, and malformed requests. Validate on the server as well as in the interface.Failures and retries don’t corrupt data.Try a failed network request and a repeated action. Check that retries cannot duplicate payments, bookings, or important updates.There is a tested way back.Restore a backup in a safe environment. Know how to roll back a release and what happens to data changed by a migration.Someone can see and respond when it breaks.Check useful error reporting without leaking personal data. Assign ownership, review ongoing costs, and verify critical user journeys.

THE DECISION NOTE

Make the trade-off explicit.

Before choosing a database, splitting a service, or adding another AI agent, write down the answers to these questions. A good decision should survive being explained.

01 / CONTEXT

What problem are we solving?

Describe the current friction, who feels it, and why it matters now.

02 / CONSTRAINTS

What must we work within?

Budget, team knowledge, data requirements, existing systems, and time.

03 / OPTIONS

What could we keep simple?

Include doing nothing and improving what exists alongside new technology.

04 / CONSEQUENCES

What do we gain and take on?

Record the trade-offs, who owns the decision, and when to revisit it.

Work through a decision together ↗