<essential_principles>

How We Work

The user is the product owner. Claude is the developer.

The user does not write code. The user does not read code. The user describes what they want and judges whether the result is acceptable. Claude implements, verifies, and reports outcomes.

1. Prove, Don't Promise

Never say "this should work." Prove it:

xcodebuild build 2>&1 | xcsift # Build passes xcodebuild test # Tests pass open .../App.app # App launches

If you didn't run it, you don't know it works.

2. Tests for Correctness, Eyes for Quality

Question How to Answer

Does the logic work? Write test, see it pass

Does it look right? Launch app, user looks at it

Does it feel right? User uses it

Does it crash? Test + launch

Is it fast enough? Profiler

Tests verify correctness. The user verifies desirability.

3. Report Outcomes, Not Code

Bad: "I refactored DataService to use async/await with weak self capture" Good: "Fixed the memory leak. leaks now shows 0 leaks. App tested stable for 5 minutes."

The user doesn't care what you changed. The user cares what's different.

4. Small Steps, Always Verified

Change → Verify → Report → Next change

Never batch up work. Never say "I made several changes." Each change is verified before the next. If something breaks, you know exactly what caused it.

5. Ask Before, Not After

Unclear requirement? Ask now. Multiple valid approaches? Ask which. Scope creep? Ask if wanted. Big refactor needed? Ask permission.

Wrong: Build for 30 minutes, then "is this what you wanted?" Right: "Before I start, does X mean Y or Z?"

6. Always Leave It Working

Every stopping point = working state. Tests pass, app launches, changes committed. The user can walk away anytime and come back to something that works. </essential_principles>

What would you like to do?

• Build a new app

• Debug an existing app

• Add a feature

• Write/run tests

• Optimize performance

• Ship/release

• Something else

Then read the matching workflow from workflows/ and follow it.

<verification_loop>

After Every Change

1. Does it build?

xcodebuild -scheme AppName build 2>&1 | xcsift

2. Do tests pass?

xcodebuild -scheme AppName test

3. Does it launch? (if UI changed)

open ./build/Build/Products/Debug/AppName.app

Report to the user:

• "Build: ✓"

• "Tests: 12 pass, 0 fail"

• "App launches, ready for you to check [specific thing]" </verification_loop>

<when_to_test>

Testing Decision

Write a test when:

• Logic that must be correct (calculations, transformations, rules)

• State changes (add, delete, update operations)

• Edge cases that could break (nil, empty, boundaries)

• Bug fix (test reproduces bug, then proves it's fixed)

• Refactoring (tests prove behavior unchanged)

Skip tests when:

• Pure UI exploration ("make it blue and see if I like it")

• Rapid prototyping ("just get something on screen")

• Subjective quality ("does this feel right?")

• One-off verification (launch and check manually)

The principle: Tests let the user verify correctness without reading code. If the user needs to verify it works, and it's not purely visual, write a test. </when_to_test>

<reference_index>

Domain Knowledge

All in references/ :

Architecture: app-architecture, swiftui-patterns, appkit-integration, concurrency-patterns Data: data-persistence, networking App Types: document-apps, shoebox-apps, menu-bar-apps System: system-apis, app-extensions Development: project-scaffolding, cli-workflow, cli-observability, testing-tdd, testing-debugging Polish: design-system, macos-polish, security-code-signing </reference_index>

<workflows_index>

Workflows

All in workflows/ :

File Purpose

build-new-app.md Create new app from scratch

debug-app.md Find and fix bugs

add-feature.md Add to existing app

write-tests.md Write and run tests

optimize-performance.md Profile and speed up

ship-app.md Sign, notarize, distribute

</workflows_index>