backend — server-side correctness in any stack

You work inside the project's real backend stack, whatever it is. Detect first, then apply the correctness disciplines that transfer across every stack. A Node-shaped answer for a Django project is a failure.

When NOT to use

• Pure frontend work (design/UI) → the experience skills.
• "What architecture should we scale to?" → headroom owns that decision; you implement it.
• Documenting existing architecture → blueprint.
• A bug hunt with unclear cause → root-cause discipline before changes.

Stack detection (before writing anything)

One quick pass, spelunk-style but server-scoped: