diff --git a/matrix/domain-coverage.md b/matrix/domain-coverage.md
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+# Domain Coverage
+
+> Where each core principle applies across the domains. The complement to `principles-matrix.md`: the matrix maps domain → core; this maps core → domains.
+
+## Core Principle Coverage
+
+| Core Principle | Domains that derive from it | Count |
+|----------------|---------------------------|-------|
+| C1 Correctness | All 11 (security, data, api, testing, performance, observability, errors, uiux, documentation, concurrency, devops) | Universal |
+| C2 Clarity | uiux, api, data, testing, observability, errors, documentation, devops | 8 |
+| C3 Simplicity | security, data, testing, performance, documentation, concurrency, devops | 7 |
+| C4 Locality | testing, concurrency | 2 |
+| C5 Reversibility | api, data, uiux, concurrency, devops | 5 |
+| C6 Composability | api, security, observability, errors, documentation, concurrency | 6 |
+| C7 Observability | api, data, testing, performance, observability, errors, devops | 7 |
+| C8 Economy | security, testing, performance, observability, concurrency | 5 |
+
+## Interpretation
+
+- **C1 Correctness** is universal — every domain derives from it. This confirms C1 as the floor.
+- **C4 Locality** is the narrowest (2 domains: testing independence, concurrency boundaries). Locality is inherently domain-specific; not a gap.
+- **C2 Clarity** and **C7 Observability** are the next-most-derived, confirming they are cross-cutting concerns.
+- **C6 Composability** appears in 6 domains — it is most relevant where parts combine (api, errors, observability, documentation, concurrency) and least relevant where the unit is monolithic.
+
+## Per-Domain Coverage
+
+| Domain | C-rules derived from | Notes |
+|--------|---------------------|-------|
+| UI/UX | C1, C2, C3, C5, C7 | User-facing; clarity + reversibility |
+| API | C1, C2, C3, C5, C6, C7 | Contracts; composability + stability |
+| Security | C1, C3, C6, C7, C8 | 8/10 non-tradeable (promoted to C1) |
+| Data | C1, C2, C3, C5, C7 | Truth + migration safety |
+| Testing | C1, C2, C3, C4, C7, C8 | Independence (C4) is unique |
+| Performance | C1, C3, C6, C7, C8 | Economy + measurement |
+| Observability | C1, C2, C6, C7, C8 | Self-referential (P7 derives from C7) |
+| Errors | C1, C2, C5, C6, C7 | Errors as data + reversibility |
+| Documentation | C1, C2, C3, C5, C6 | Docs-as-code + living docs |
+| Concurrency | C1, C3, C4, C5, C6, C7, C8 | Broadest derivation; locality (C4) unique |
+| DevOps | C1, C2, C3, C5, C7 | Reproducibility + rollback |
+
+## Gaps and Notes
+
+- No domain derives from only one C-rule. The minimum is 4 (UI/UX: C1, C2, C3, C5, C7 — actually 5). Every domain is multi-rooted.
+- **Concurrency** has the broadest derivation (7 C-rules) — it touches the most core concerns.
+- **UI/UX** and **API** are the most user-facing; they emphasize C2 (Clarity) heavily.
+- **Security** is the only domain with explicit non-tradeable declarations; this promotes 8 of its rules to C1-equivalent per `core/conflict-resolution.md` §6.
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diff --git a/review/agent-checklist.md b/review/agent-checklist.md
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+# Agent Pre-Completion Checklist
+
+> Every AI agent runs this checklist before completing a task. If any item fails, fix it before finishing. This is the gate between "the code is written" and "the task is done."
+
+## How to Use This
+
+1. Read the relevant `domains/<x>/first-principles.md` before starting the task.
+2. Implement the task.
+3. Run this checklist. Every item must pass (or be explicitly justified).
+4. If an item fails, fix it. Do not "skip" without a written reason.
+
+## Core Principles Checklist (C1–C8)
+
+### C1 Correctness
+- [ ] Does the code do what the task asked, completely?
+- [ ] Does it handle the specified edge cases? (nulls, empties, max, min)
+- [ ] Does it handle the failure cases? (errors, timeouts, invalid input)
+- [ ] Is there a test that would fail if the code were wrong?
+
+### C2 Clarity
+- [ ] Can a stranger read this and understand it without asking you?
+- [ ] Are names intent-revealing? (No `data`, `temp`, `x`, `doStuff`)
+- [ ] Do comments explain *why*, not *what*?
+- [ ] Is the structure scannable? (Short functions, clear sections)
+
+### C3 Simplicity
+- [ ] Is this the simplest solution that is complete?
+- [ ] Is there dead code? (Unreachable branches, unused variables)
+- [ ] Is there premature abstraction? (An interface with one implementation)
+- [ ] Could 50 lines do what 200 lines do?
+
+### C4 Locality
+- [ ] Does related logic live together?
+- [ ] Are side effects near their causes?
+- [ ] Does a change to this feature require touching distant files?
+
+### C5 Reversibility
+- [ ] Is this change undoable? (migration has a `down`, deploy has a rollback)
+- [ ] Did I avoid irreversible actions without explicit confirmation?
+- [ ] Is state recoverable? (Can the user get back to where they were?)
+
+### C6 Composability
+- [ ] Does this component/function do one thing?
+- [ ] Is the boundary (props/args/return) explicit and typed?
+- [ ] Can this be reused in a new context without modification?
+
+### C7 Observability
+- [ ] Are there logs for significant events?
+- [ ] Do errors carry enough context to debug? (request ID, user, action)
+- [ ] Are there metrics for the operation? (count, latency)
+- [ ] Are there no secrets in logs?
+
+### C8 Economy
+- [ ] Is memory bounded? (No unbounded growth, no loading everything)
+- [ ] Is time bounded? (No N+1, no blocking without timeout)
+- [ ] Are resources released? (file handles, connections, locks)
+
+## Domain-Specific Triggers
+
+If the task touches a domain, run that domain's checklist:
+
+### If UI/UX (see `domains/uiux/`)
+- [ ] Every interactive element is keyboard-reachable
+- [ ] Every image has alt text (or marked decorative)
+- [ ] Every form control has a label
+- [ ] Focus is visible
+- [ ] No color-only information
+- [ ] Components use design tokens, not raw values
+
+### If API (see `domains/api/`)
+- [ ] Endpoints are nouns, plural, lowercase-hyphenated
+- [ ] Status codes are correct (200/201/204/4xx/5xx per semantics)
+- [ ] Errors are structured (code, message, request_id)
+- [ ] Input is validated against a schema
+- [ ] Auth is required by default
+
+### If Security (see `domains/security/`)
+- [ ] No secrets in code, logs, URLs, or error messages
+- [ ] Input is validated at the boundary
+- [ ] Output is encoded for its context
+- [ ] Crypto uses vetted libraries (no MD5/SHA1 for security)
+- [ ] Authorization is checked, not assumed
+
+### If Data (see `domains/data/`)
+- [ ] Schema reflects the domain (not the application)
+- [ ] Constraints are in the schema (NOT NULL, UNIQUE, FK)
+- [ ] Migration has an `up` and a `down`
+- [ ] Types are domain-accurate (UUID, TIMESTAMPTZ, DECIMAL for money)
+- [ ] No `SELECT *`; no N+1
+
+### If Testing (see `domains/testing/`)
+- [ ] Tests are independent (order doesn't matter)
+- [ ] Tests are deterministic (no `Date.now()`, no `random()`)
+- [ ] Edge cases are covered (empty, single, max, invalid)
+- [ ] A failing test names the problem specifically
+
+### If Performance (see `domains/performance/`)
+- [ ] No unbounded operations (loops, allocations, queries)
+- [ ] No N+1 queries
+- [ ] Every external call has a timeout
+- [ ] Caches have invalidation strategies
+
+### If Observability (see `domains/observability/`)
+- [ ] Logs are structured (JSON, fields)
+- [ ] Every request has a correlation ID
+- [ ] No high-cardinality labels in metrics
+- [ ] Alerts have runbooks
+
+### If Errors (see `domains/errors/`)
+- [ ] Errors are not swallowed silently
+- [ ] Errors are specific (not generic "something went wrong")
+- [ ] Errors preserve context (where, when, why, what)
+- [ ] Recovery is attempted when possible; fail fast when not
+
+### If Concurrency (see `domains/concurrency/`)
+- [ ] Shared state is minimized; immutability preferred
+- [ ] Locks are minimal in scope
+- [ ] Queues are bounded
+- [ ] Every blocking call has a timeout
+- [ ] Cancellation is supported
+
+### If DevOps (see `domains/devops/`)
+- [ ] The pipeline is the process (no manual steps)
+- [ ] Rollback path is known
+- [ ] Config is in code, not on the server
+- [ ] Environments are parity (dev = prod modulo data)
+
+## Final Gate
+
+- [ ] Have I read the relevant domain's first-principles?
+- [ ] Have I run the domain-specific checklist?
+- [ ] Have I run the core checklist?
+- [ ] Are all failures either fixed or explicitly justified in the task notes?
+
+If any unchecked item is not justified, the task is not complete. Do not mark done.
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diff --git a/review/anti-patterns.md b/review/anti-patterns.md
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+# Anti-Patterns
+
+> A catalog of violations. Each entry names the principle it breaches. Use this to recognize and reject patterns on sight.
+
+## How to Use
+
+When you see a pattern listed here, it is a defect. Cite the principle it violates and require a fix. These are not "to be reviewed later"; they are rejected on sight.
+
+## Core Anti-Patterns (C1–C8)
+
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| Code that "mostly works" | C1 Correctness | Mostly correct is incorrect |
+| `function doStuff()` | C2 Clarity | Name reveals nothing |
+| A 500-line function | C3 Simplicity | Complexity is a liability |
+| Config in a distant repo, read silently | C4 Locality | Coupling you cannot see |
+| A migration with no `down` | C5 Reversibility | Irreversible bet |
+| A component reading global state implicitly | C6 Composability | Hidden dependency |
+| A service with no logs | C7 Observability | Cannot debug what you cannot see |
+| Loading all records into memory | C8 Economy | Unbounded = OOM |
+
+## Domain Anti-Patterns
+
+### UI/UX
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| Image without `alt` | P2 Accessibility | Disqualifying |
+| "Delete" with no confirmation | P5 Forgiveness | Irreversible surprise |
+| `color: #3b82f6` in a component | P8 Consistency (via tokens) | Bypasses design system |
+| "Submit" on a delete button | P3 Clarity | Wrong verb |
+| Layout shift on image load | P7 Hierarchy / CLS | Visual instability |
+
+### API
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| `/getUsers` (verb in URL) | P2 Clarity | Resources are nouns |
+| 200 with an error body | P9 Error Transparency | Status code lies |
+| 500 with a stack trace | P8 Security, P9 | Information leak |
+| No `Idempotency-Key` on a POST | P6 Idempotency | Retry is unsafe |
+| 10MB response by default | P7 Performance | Unbounded payload |
+
+### Security
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| `eval()` of any string | P4, P5 | Code injection |
+| Hardcoded API key in source | P9 Secret Hygiene | Committed secret |
+| `catch (e) {}` (swallow) | P7, P8 | Silent failure, fail-open |
+| `md5` for password hashing | P6 Crypto | Broken primitive |
+| Open CORS `*` in production | P1, P10 | Zero trust violated |
+| `chmod 777` | P2 Least Privilege | Maximum privilege |
+| Logging the request body | P9 Secret Hygiene | Token leak |
+
+### Data
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| `VARCHAR` for a UUID | P7 Type Fidelity | Wrong type |
+| No FOREIGN KEY | P3, P9 | Unenforced relationship |
+| `FLOAT` for money | P7, P1 | Floating point error |
+| `is_deleted` without filtering | P8 Lifecycle | Soft-delete leak |
+| `SELECT *` | P10 Performance | Unbounded columns |
+
+### Testing
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| Test that cannot fail | P10 No Test Theater | Not a test |
+| `Date.now()` in a fixture | P3 Determinism | Flaky |
+| Shared fixture mutated across tests | P2 Independence | Order-dependent |
+| 500 e2e tests, 50 unit | P4 Fast Feedback | Inverted pyramid |
+| `name: "test"` fixture | P7 Realism | Hides bugs |
+
+### Performance
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| N+1 query in a loop | P3 Complexity | O(N) queries |
+| No timeout on HTTP call | P4, P8 (concurrency) | Hang forever |
+| Cache with no invalidation | P5 Caching | Stale forever |
+| Unbounded in-memory sort | P4 Resource Bounds | OOM |
+| Optimization without measurement | P1 Measure First | Guesswork |
+
+### Observability
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| `console.log("here")` | P1 Structured | Not queryable |
+| `user_id` as a metric label | P4 Cardinality | Unbounded bill |
+| Average latency only | P8 SLO | Hides the tail |
+| No `trace_id` propagation | P2 Correlation | Cannot trace |
+| Logs without `request_id` | P3 Context | No correlation |
+
+### Errors
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| `catch (e) { return null }` | P2 Fail Loudly | Silent failure |
+| `throw new Error("error")` | P3 Fail Specifically | Generic |
+| `return null` for "not found" | P1 Errors are Data | Conflates absence with error |
+| Retry without backoff | P5, P8 | Retry storm |
+| `throw` in a recovery path | P6 | Fail fast in wrong place |
+
+### Documentation
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| Doc with no examples | P3 Examples | Incomplete |
+| Stale doc (wrong, not updated) | P4 Currency | Worse than no doc |
+| Unlisted doc (not in MANIFEST) | (framework rule) | Not part of framework |
+| No audience statement | P2 Audience | Who is this for? |
+
+### Concurrency
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| Shared mutable state, no lock | P1 Immutability | Race condition |
+| Unbounded queue | P9 Bounded Queues | OOM |
+| `channel.send()` with no timeout | P8 Timeout | Hang |
+| Mutex held across I/O | P3 Lock Scope | Lock too long |
+| Spawned work with no cancellation | P7 Cancellation | Orphaned work |
+
+### DevOps
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| Manual deploy script | P2 Automation | Not repeatable |
+| No rollback path | P4 Rollback | Irreversible deploy |
+| Big-bang deploy | P5 Progressive | All-or-nothing |
+| Rebuild per environment | P7 Immutability | Different artifacts |
+| Snowflake server | P1, P6 | Not reproducible |
+
+## Cross-Cutting Anti-Patterns
+
+| Anti-Pattern | Breaches | Why |
+|--------------|----------|-----|
+| "I'll add tests later" | C1 (no proof of correctness) | Later never comes |
+| "It's just a prototype" | C5 (irreversible by default) | Prototypes go to prod |
+| Copy-paste code | C6 (no composition) | Bug duplicated |
+| God object | C3, C6 | One thing, many things |
+| Leaky abstraction | C6, C2 | Hidden coupling |
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diff --git a/review/peer-review-checklist.md b/review/peer-review-checklist.md
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+# Peer Review Checklist
+
+> For human reviewers. Run this when reviewing a PR or a change. Complements `agent-checklist.md` (which the author ran before finishing).
+
+## Purpose
+
+A peer review is a second set of eyes on correctness, clarity, and completeness. It is not a gatekeeping ritual; it is a quality multiplier. The author ran the agent checklist; the reviewer checks what the author could not see.
+
+## The Review
+
+### Understanding (read first, judge never)
+- [ ] Read the PR description. What is the change trying to do?
+- [ ] Read the linked issue/spec. Does the change address it?
+- [ ] Read the changed files in order. Do not jump to judgment.
+
+### Correctness (C1)
+- [ ] Does the change do what it claims?
+- [ ] Are there edge cases the author missed? (Comment, don't fix in review)
+- [ ] Are there failure cases unhandled?
+- [ ] Are the tests testing the right thing? (A test that cannot fail is theater)
+- [ ] Would this code fail in production? (Different from "does it pass CI")
+
+### Clarity (C2)
+- [ ] Can you understand the change without asking the author?
+- [ ] Are names intent-revealing?
+- [ ] Is there a comment that explains *why* where the *why* is non-obvious?
+- [ ] Is the diff minimal? (Unrelated changes are review noise)
+
+### Simplicity (C3)
+- [ ] Is there dead code introduced?
+- [ ] Is there premature abstraction?
+- [ ] Could the change be simpler? (Suggest, don't block unless egregious)
+- [ ] Is there a simpler approach the author may not have considered?
+
+### Locality (C4)
+- [ ] Are related changes grouped?
+- [ ] Are unrelated changes separated (different PRs)?
+- [ ] Does a change require touching distant files unnecessarily?
+
+### Reversibility (C5)
+- [ ] Is the change undoable?
+- [ ] Are there migrations? Do they have rollbacks?
+- [ ] Are there breaking changes? If so, is there a deprecation path?
+
+### Composability (C6)
+- [ ] Does the change respect existing boundaries?
+- [ ] Does it introduce coupling that should be an interface?
+- [ ] Is the new code reusable, or one-off?
+
+### Observability (C7)
+- [ ] Are there logs/metrics for the new behavior?
+- [ ] Are errors structured and traceable?
+- [ ] Are there no secrets in logs?
+
+### Economy (C8)
+- [ ] Are there unbounded operations?
+- [ ] Is memory/time bounded?
+- [ ] Is the cost proportional to the need?
+
+## Domain-Specific (if applicable)
+
+Run the relevant domain section from `agent-checklist.md` (UI/UX, API, Security, Data, Testing, Performance, Observability, Errors, Concurrency, DevOps). The author ran it; the reviewer verifies.
+
+## Review Etiquette
+
+- **Comment, don't command.** "This could be X" not "Change this to X."
+- **Distinguish blocking from suggestions.** "Blocking: correctness bug. Suggestion: naming."
+- **Praise good code.** Reviews are not just for finding problems.
+- **Don't review style the linter should catch.** Fix the linter, not the PR.
+- **Ask questions.** "Why this approach?" often reveals more than "This is wrong."
+
+## Approving
+
+- Approve when: the change is correct, clear, and complete. Minor suggestions can be left for the author.
+- Request changes when: there is a correctness bug, a missing test, or a clarity problem that blocks understanding.
+- Reject when: the change should not exist (wrong direction, duplicate, scope-violating).
+
+## What This Checklist is Not
+
+- Not a style guide. Style is automated (linter, formatter).
+- Not a gatekeeping tool. The goal is quality, not perfection.
+- Not a substitute for the author's own checklist. The author runs `agent-checklist.md` first; this is the second pass.
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