Glossary | The Engineer's Manual

Terms as used in this manual.

Levels of Work

Problem: An undefined challenge to solve. No clear solution yet. Requires discovery to define what success looks like.

Initiative: A defined objective that solves a Problem. Weeks or months of work. Decomposes into Epics.

Epic: A major phase of an Initiative. Delivers a meaningful milestone. Runs through P-Cubed. Produces Tasks.

Task: A specific action. 1-2 days of focused work. Clear acceptance criteria.

P-Cubed: Prepare → Prove → Produce. The cycle for executing an Epic.

Prepare: The phase where you build understanding, surface tradeoffs, and plan the work.

Prove: The phase where you validate load-bearing decisions before committing.

Produce: The phase where you execute tasks, verify against criteria, and ship.

Discovery: The sub-phase of Prepare where you explore the problem space, ask questions, and build understanding.

Spike: A time-boxed experiment to validate a technical assumption or approach.

Load-Bearing: A decision that's hard to change after you build on top of it. Requires extra rigor upfront.

Architecture: The structural decisions in a system. Database schema, service boundaries, core abstractions. Hard to change.

Design: The surface decisions in a system. API shape, UI components, implementation details. Easier to change.

Tradeoff: What you give up when you choose one approach over another. There's no free lunch.

TDD: Test-Driven Development. Write the test first, then implement to make it pass.

GOOS: Growing Object-Oriented Software, Guided by Tests. Outside-in, mockist-style TDD.

Trunk-Based Development: Short-lived branches, frequent integration to main. Every commit is deployable.

Done: The acceptance criteria are met. Not "feels done." Criteria met.

Acceptance Criteria: The specific, checkable conditions that define when a Task is complete.

Mental Model: Your internal representation of how a system works. How you predict behavior.

Add terms as you encounter them.