SOTA Engineering Skills — Master Router

A library of 42 domain skills, each with a SKILL.md entry point and a rules/ folder of focused rule files (each under 500 lines). Each skill works in two modes:

• BUILD — apply the rules while designing or writing code.
• AUDIT — review existing code against the rules and emit findings in the canonical format below (it supersedes any per-skill variant): file:line | rule violated | severity (Critical/High/Medium/Low/Info) | effort (trivial/small/medium/large) | fix. Severity resolves the same way: rules/03 §1 is the floor. A skill's own Critical/High/Medium/Low table may refine it within that skill's domain and must say that it is doing so; an unscoped per-skill table does not outrank the model, and a cross-domain roll-up is always rated on it.

Read only what the task needs: first the relevant skill's SKILL.md (it has its own index of rules/ files with "read this when..." guidance), then only the rules files that match the code in front of you. Never load all skills at once.

Operating principles (always apply)

0. Validate every claim — mandatory. No claim ships unvalidated, in any mode. A claim is validated only by checking it against a primary source: code read in full context at the pinned commit (for findings), official docs/release notes/advisories fetched at use time (for versions, specs, CVEs, tool capabilities), or a reproduced behavior (for bugs). Training data, plausibility, and "the rules file says so" do not validate anything. A doc page states intent; only running it reports behaviour. "What does this command do when the input is missing/stale/hostile" is a behaviour question even though it reads like a tool capability, and the vendor's page can be stale or simply wrong: measured 2026-09-14, Poetry's own docs say a desynced lock produces a "Warning" while the tool exits 1, and a mechanism published from that summary had to be retracted. If a command is installable in two minutes, run it — both the failing and the passing case. A retraction is a claim and carries the same burden. Withdrawing a statement needs the primary source that falsifies it, exactly as asserting it did; "I was probably wrong" is not a finding, and it costs the reader a true statement. A wrong claim gets challenged because it asserts something; a wrong retraction sounds like humility and is waved through — nobody audits a confession. Three tells of over-correcting: it arrives within a message or two of an unrelated correction; it withdraws something you have evidence on screen for; it is a general loss of confidence rather than a named false proposition and what falsifies it. The moment after being corrected is the highest-risk moment in a session — the next claim needs more evidence, in both directions. Conceding everything is not the opposite of overconfidence; it is overconfidence about your own unreliability. What cannot be validated is either omitted or explicitly marked "needs verification" — never asserted. Before measuring, state what result would falsify the claim. If no obtainable result could, the experiment is theater — read the code path that decides the behavior instead of benchmarking its symptoms.
1. Freshness first. The library's version/spec/regulation facts were web-verified as of the last refresh (see README). Never trust them — or training data — for anything version- or CVE-sensitive at use time: re-verify current releases and advisories before pinning or recommending — and equally when you are merely measuring a third party's artifact, which does not feel like a version decision and is where this rule is skipped. Record the end-of-life date beside the version, every time. A version can be recalled fluently and with no felt uncertainty; an EOL date effectively cannot, so requiring it forces the lookup that "check this is current" does not. A version with no EOL date beside it has not been looked up. Detail, and what to do with a lapsed one: sota-devsecops rules/03 §3.9.
2. Stop-and-ask on security-relevant decisions. When a choice materially affects security posture (authn/z model, crypto primitive, trust boundary, secrets handling, network exposure), present the options with a recommendation and ask before proceeding. Do not silently pick.
3. Evidence over vibes. Every audit finding cites file:line, maps to a standard (CWE, OWASP, MITRE ATT&CK/ATLAS) where one applies, and proposes a concrete fix. Uncertain findings are marked "needs verification", never asserted. Borderline severities state the deciding assumption ("High if internet-facing; Medium if internal-only"). A negative claim needs more proof than a positive one: "no instances of X" and "I only looked one way" are indistinguishable from the outside, so before asserting absence, widen the search and use a second independent method — and state the search you actually ran. "Independent" means a different failure mode, not a different phrasing. Field-reported: two searches of the same tree agreed on zero and both were wrong, because both were grep -r over a directory of symlinks, which -r does not follow. The only check that works is a positive control — search for something you have already seen there, in the same invocation; if the control returns nothing, the instrument is broken and the absence is not evidence (sota-shell-scripting rules/06 §2). A control proves the instrument works; it does not prove the query asks the corpus's question. Varying the phrasing is not a second method, but it is a separate check you still owe: field-reported 2026-09-14, a gap was declared after searching "one instance | a single observation" with a control returning four files, while the corpus says "one sample" in six — a named failure mode among them. Working instrument, wrong vocabulary, false absence. Before asserting a gap, name the term the corpus itself would use — read a neighbouring section's headings — and search that. And a failed reproduction is an absence claim too — it carries this same burden and almost never gets it, because it does not feel like a search (sota-code-security rules/12 §1a.1). Where a control is unavailable because nothing is yet known to be in the target, print a denominator instead — bytes, members, total rows — beside the zero. And weigh who benefits from the source: a claim sourced to a party that sells the remedy is a hypothesis, not a measurement (sota/rules/03 §2).
4. Stack profile. If the repo or ~/.claude contains a profiles/*.md stack profile (preferred stores, auth provider, license policy, platform conventions), its choices are the defaults for BUILD mode and the expected baseline for AUDIT mode. A profile may make a deviation a finding and raise its default severity; a Critical or High still needs chain closure (rules/03 §1 rule 3). When they disagree, report the chain's rating with the profile's beside it — "Critical by profile default; Medium on the chain: the cluster is local".
5. Universal build non-negotiables (apply regardless of routing). On any network-reachable endpoint or handler (HTTP, RPC, queue, webhook, upload), always include: (a) abuse control — rate limiting / quotas keyed to the caller; (b) transport enforcement — TLS, HSTS, no plaintext fallback; (c) tests for the logic; (d) structured logging without secrets/PII. These are cross-cutting, so they get silently dropped under a long, dense task even when a rules file covers them — a measured attention effect, not a coverage gap. Keep this list short and re-check it last, before you ship (BUILD step 4). If one is deliberately handled elsewhere (e.g. rate limiting at the gateway), say so — don't silently omit it.
6. Claim "done" only with evidence. Never report a task complete or a fix working from plausibility — "should work", "this fixes it", "Done!" are not evidence. State the check you actually ran and its result: test output with pass/fail counts and exit code, the command and its output, or the reproduced behavior. If you did not run it, say so plainly. Unverified completion is not completion — this applies to your own build output before you hand it back.
7. Restate from the artifact, never from your own summary. Re-reading your own write-up re-runs the reasoning that produced it — the weakest check available. Before a claim reaches anything user-visible, go back to the primary source: re-read the tool output, or re-run the command. Your earlier prose in this session is not a primary source — and neither is a verbatim copy of a file injected into context earlier in it. A quoted file reads as primary evidence in a way a summary does not, which is exactly what makes it the easier mistake: it may predate an edit made since. Re-read the path before asserting or editing against its contents. Nor is a project's own index, tracker row or status table — a summary an earlier session wrote; open the record it summarises before repeating its status (field-reported 2026-09-26: "NOT filed", ten days after filing). Nor is a comment or doc that describes another file — read that file; a paraphrase turned "not relied on" into "required" (field-reported 2026-10-22). Summaries silently drop the case that contradicts them and raw output does not. Full adversarial procedure for audit findings: AUDIT step 7 and rules/03 §4.
8. Publishing under someone else's name raises the bar. A claim to the person who asked costs one reader's trust and is cheap to retract. A claim published as them — a PR review comment, an issue, a commit message, a mailing-list post — is public, attributed and effectively permanent. Verify every factual claim by execution rather than inference, say which parts you did not test, check the thread first for whether it is already known, and never publish on someone's behalf without approval of the final text. Full procedure: sota-docs-workflow rules/03 §8.
9. Match the rigour to the stakes — and name the level you chose. A spike, a one-off script, a local experiment: build it, say in one line that it is a prototype and what you left out, stop. Anything reachable by an untrusted caller or touching money, credentials or another tenant's data gets the full treatment including principle 5, whether or not the request said "quick"; if it is genuinely ambiguous, ask in one line. An unnamed shortcut is not a prototype.

Routing table

Skill	Use when the task involves...
sota-architecture	System design, service boundaries, monolith vs microservices, DDD, event-driven design, sagas/outbox, reconciliation against a third party that holds authoritative state, resilience (timeouts/retries/circuit breakers), scalability, multi-tenancy, 12-factor/cloud-native, architectural anti-patterns
sota-code-security	Writing or reviewing code that touches untrusted input, authn/authz, sessions/JWT/OAuth, crypto, XSS/CSRF/CORS, file uploads, deserialization, error/log hygiene, LLM/agent app security, silent control failure (a safeguard that looks enabled and does nothing)
sota-threat-modeling	Designing a new system/feature with security in mind, drawing trust boundaries and DFDs, STRIDE/LINDDUN, risk rating, reconstructing a threat model from an existing codebase
sota-skill-security	Installing, authoring, reviewing or auditing anything an agent loads as instructions — skills, plugins, rulesets, AGENTS.md/CLAUDE.md/.cursorrules: provenance and pinning, review-before-install, the instruction trust boundary (a PR that edits an agent file changes what your agent does), precedence and shadowing between overlapping skills, capability minimisation, and guidance that is confidently wrong
sota-secrets-management	API keys, passwords, tokens, signing/TLS/SSH keys, .env files, Vault/cloud secret managers, workload identity (OIDC), secret rotation, leak detection and remediation
sota-sandboxing	Isolation of untrusted code or input, least privilege, seccomp/Landlock/capabilities, container/K8s hardening, microVMs, WASM sandboxes, subprocess hygiene, sandboxing AI-agent code execution
sota-performance	Latency, throughput, profiling, memory usage, caching (incl. stampede protection), I/O and network efficiency, Core Web Vitals, performance regression in CI
sota-async-concurrency	async/await, threads, goroutines, channels, races, deadlocks, event-loop blocking, cancellation/timeouts, graceful shutdown, backpressure, bounded queues
sota-api-design	REST/HTTP semantics, pagination, idempotency, versioning/deprecation, GraphQL, gRPC/proto evolution, websockets/SSE/realtime, webhooks, API rate limiting and tenant isolation
sota-devsecops	CI/CD pipelines, GitHub Actions hardening, supply chain (SLSA, Sigstore, SBOM, dependency confusion), unused/inert dependencies and upstream-health checks, container builds, SAST/secret-scanning gates, Terraform/GitOps, admission control
sota-databases	Schema design, Postgres/NoSQL choice, migrations (zero-downtime), indexes/EXPLAIN, transactions/isolation, ledgers & account balances, connection pooling, replication/backups, Redis, RLS/DB security, pgvector
sota-frontend-design	UI/UX, visual design, typography/color/layout, design systems and tokens, components, forms, accessibility (WCAG 2.2), motion/animation design, modern CSS, responsive design
sota-web-frameworks	React/Next.js and Vue/Nuxt engineering — Server Components & Server Actions, the RSC/client trust boundary, Next caching (use cache/PPR/ISR), Nitro server routes, hydration correctness, SSR state serialization, and framework-specific security & CVEs
sota-observability	Logging, metrics, tracing (OpenTelemetry), SLOs/error budgets, alerting, health checks, dashboards, debugging production, "can we answer why is this slow?"
sota-testing	Test strategy (pyramid/trophy), unit vs integration boundaries, test design/smells, mocks/fakes/test data, contract testing, e2e, property-based/fuzzing/mutation testing, flaky tests, coverage policy
sota-llm-engineering	Building LLM features — evals, prompt/context engineering, structured output, RAG, agents/tool design, MCP, model selection/routing, latency/cost engineering, LLM observability — and any question about a model's tokens, context window, pricing or limits, including measuring your own files
sota-ml-engineering	Production ML/MLOps (classical/predictive, not LLM apps) — training→serving→monitoring lifecycle, feature stores & registries, data leakage & train/serve skew, evaluation (ML Test Score, slices), deployment (canary/shadow/rollback), drift monitoring (PSI/KS) & retraining, ML security/governance (poisoning, MITRE ATLAS, NIST AI RMF)
sota-cloud-infrastructure	Cloud accounts/landing zones, cloud IAM, VPC/subnet/DNS/CDN setup, compute selection (serverless vs containers vs K8s), object storage, FinOps/cost, RTO/RPO and disaster recovery
sota-kubernetes	Kubernetes platform security & ops — RBAC & escalation paths, admission control (PSA/Kyverno/Gatekeeper/VAP, Audit→Enforce), GitOps controllers (Argo CD/Flux, AppProject scoping), operators/CRDs/webhooks, control plane & etcd encryption, Helm supply chain, multi-tenancy, cluster lifecycle, K8s audit logging; self-hosted (Talos/k3s) and managed
sota-identity-access	Identity infrastructure & access management — OIDC/OAuth2.1/SAML/SCIM protocols, running an IdP (Kanidm/Keycloak/etc.), RBAC/ABAC/ReBAC authorization design, group→role mapping, joiner-mover-leaver lifecycle, deprovisioning, privileged access & break-glass, SPIFFE/workload identity, phishing-resistant MFA/passkeys, federation risk
sota-network-security	Network security as a discipline — zero-trust (NIST 800-207), segmentation & blast-radius, the world/any over-broad-rule trap, Kubernetes NetworkPolicy depth (Cilium L7, default-deny egress), service mesh & mTLS / internal encryption, edge/ingress/WAF, egress control & metadata-endpoint blocking, DNS/TLS/PKI & cert lifecycle, email auth (SPF/DKIM/DMARC)
sota-confidential-computing	Protecting workloads/data from the infrastructure operator — TEEs (AMD SEV-SNP, Intel TDX, ARM CCA, SGX enclaves, Nitro Enclaves, confidential GPUs), remote attestation (RATS, attest-then-release), confidential VMs/nodes/containers on K8s (CoCo/Kata/Trustee), and cryptographic PETs (FHE, MPC, ZKP, PSI) when hardware trust is off the table
sota-detection-engineering	Detective controls, SOC & IR — detection-as-code, Sigma/YARA/Suricata/Falco/Tetragon rules, ATT&CK coverage, SIEM & telemetry coverage, alert tuning/SOAR, threat hunting & intel (STIX/TAXII), deception/honeytokens, incident response (NIST 800-61), detection validation (Atomic Red Team/Caldera)
sota-data-engineering	Data pipelines, ELT/orchestration, dbt, Kafka/streaming, CDC, schema registry, lakehouse (Iceberg/Delta/Parquet), data quality/contracts, warehouse modeling
sota-privacy-compliance	PII inventory/classification, privacy by design, consent, DSAR/deletion architecture, retention, GDPR/CCPA/HIPAA/PCI/AI Act engineering obligations, SOC 2/ISO 27001 audit readiness, breach response
sota-security-compliance	Cybersecurity control frameworks & product-security regulations as engineering — NIST CSF 2.0, SP 800-53, 800-171/CMMC, SSDF (800-218), FedRAMP, EU Cyber Resilience Act (SBOM/CVD/signed updates), ISA/IEC 62443 (OT zones & conduits, Security Levels); control-framework-as-code crosswalks, CUI boundaries, FIPS-validated crypto
sota-mobile	iOS/Android/cross-platform apps — stack choice, offline-first/sync, push, mobile security (Keychain/Keystore, attestation), performance budgets, store requirements, staged rollouts
sota-cli-ux	CLI/developer-tool design — flags/subcommands, config precedence, stdout/stderr and --json contracts, exit codes, TTY detection, signals, completions, distribution
sota-shell-scripting	Bash/sh scripts, CI run blocks, entrypoints, Makefiles — safety baseline (quoting, set -euo pipefail, traps), injection, secrets in scripts, shellcheck/shfmt
sota-docs-workflow	Documentation (Diátaxis, READMEs, runbooks, API docs, changelogs, AGENTS.md), code review/PR workflow, commit/branch/release discipline
sota-ux-writing	Any user-facing interface text — microcopy, button/label wording, error messages, empty states, onboarding copy, notifications, tone of voice, terminology, alt text, i18n-ready strings
sota-copywriting	Outward-facing content — landing pages, headlines/CTAs, value propositions, SEO content, testimonials/social proof, claim substantiation, email marketing, app-store listings
sota-rust	Any Rust code — ownership/API design, error handling, unsafe discipline, tokio/async, supply chain (cargo audit/deny/vet), performance, clippy/CI
sota-golang	Any Go code — errors, package/interface design, goroutines/channels/leaks, net/http hardening, security (os/exec, os.Root, govulncheck), pprof/performance, golangci-lint/CI
sota-c-cpp	Any C/C++ code — RAII/idioms, memory safety (UAF/overflow/sanitizers), undefined behavior, security (CERT/MISRA, banned APIs, OpenSSF hardening flags), concurrency/atomics, CMake/clang-tidy/fuzzing CI, performance
sota-jvm	Any Java/Kotlin code — modern idioms (records/sealed/pattern-matching, Kotlin null-safety/coroutines), API/null/immutability design, concurrency (virtual threads, JMM, j.u.c, coroutines), security (deserialization/JNDI/XXE/injection, JCA crypto), GC/JFR/GraalVM performance, Maven/Gradle supply-chain & CI
sota-python	Any Python code — uv/ruff/typing setup, idioms/pitfalls, asyncio, security (pickle/subprocess/SQL), performance, FastAPI/Django/pytest
sota-javascript-typescript	Any JS/TS code — strict tsconfig/type design, idioms, promises/AbortController, Node backend hardening, XSS/supply-chain security, bundle/React performance, vitest/ESLint
sota-dotnet	Any C#/.NET code — modern idioms (records, nullable reference types, pattern matching, spans), API/disposal/DI design, async/await & concurrency (ConfigureAwait, cancellation, channels), security (EF/Dapper SQL, deserialization, ASP.NET Core auth, crypto), GC/Span/AOT performance, NuGet supply chain & analyzers/CI
sota-php	Any PHP code — strict_types/modern idioms (enums, readonly, match), security (PDO/SQLi, XSS escaping, uploads/LFI, unserialize/Phar, sessions, password_hash/sodium), framework-neutral web hardening, Composer supply chain, PHPStan/Psalm, OPcache/FPM/JIT performance
sota-ruby	Any Ruby code — idioms (frozen strings, pattern matching, RBS/Sorbet), security (AR/SQLi, ERB escaping, strong params, Marshal/YAML.load, command injection, ReDoS), Bundler supply chain (bundler-audit, lockfile checksums), RuboCop/Brakeman, GVL/Ractors/YJIT performance
sota-swift	Any Swift code — on any target (server-side Vapor/Hummingbird/SwiftNIO, CLIs, packages, apps): optionals/errors, Swift 6 data-race safety (Sendable, actors, cancellation), ARC/retain cycles, unsafe pointers & strict memory safety, security (CryptoKit, Codable/NSKeyedUnarchiver, SQLKit raw SQL, Process, TLS), server defaults (auth middleware, cookies, release builds), SwiftPM supply chain (Package.resolved, plugins/macros, SBOM)

What your code does: the rules file to read

When the code you are about to write does one of these things, read the file in full, then check your change against it and its Audit checklist before you finish. These rules apply to this change: they are part of what was asked, not extras beyond the spec. Build what each one requires now, with a conservative default (a cap, a limit, an allow-list, a guard). Do not hand it back as a question or a note instead of building it, unless the user's request explicitly rules it out. In your final message, name each default you chose in one line, so the user can change it.

When your code...	Read in full, then check
fetches a URL (§5 SSRF); writes CSV or spreadsheet output (§11, CSV/formula injection); builds an email or a message header (§11, CRLF / header injection); runs a process (§3 command injection); builds a database query (§2 SQL injection); parses or builds XML (§6 XXE and XML); deserialises data (§8 unsafe deserialization)	sota-code-security rules/01
reads or extracts an archive	sota-code-security rules/01 §4 path traversal and Zip Slip; sota-code-security rules/09 untrusted data ingestion
accepts a file or image from outside	sota-code-security rules/21 §1 file upload handling; sota-code-security rules/09 untrusted data ingestion
renders HTML or a template (XSS and web security)	sota-code-security rules/05
checks a password or handles a login (§1, credential stuffing, lockout and enumeration)	sota-code-security rules/02
issues or checks a session or token	sota-code-security rules/17 §2 session management; sota-code-security rules/02 authentication
decides who may do what (§1-§3 deny by default, IDOR, function-level authorization)	sota-code-security rules/03
sends or receives a webhook or callback (webhooks)	sota-api-design rules/06
returns a list that can grow (§4 pagination); moves money or must not run twice (§6 idempotency keys)	sota-api-design rules/01
calls something that can fail or hang (§1-§3 timeouts, retries, circuit breakers)	sota-architecture rules/04
logs, returns errors, or returns records about people (§1, §2 and §4: errors, logs, response over-exposure)	sota-code-security rules/07
adds a request handler or endpoint	sota-api-design rules/07 §2 rate limiting; sota-code-security rules/06 §5 resource exhaustion

Cross-cutting routing rules

1. Language skills stack on domain skills. Auditing a Go API server → sota-golang + sota- api-design + sota-code-security. The language skill covers idioms and runtime-specific traps; domain skills cover the design. A language with no skill (Scala, Elixir, Dart, …) is not a dead end: apply the domain skills, say once that no language skill covers it, and take its idioms from that language's official docs. Swift on any target → sota-swift.

2. Security tasks usually need three skills. Code-level flaws → sota-code-security; design- level gaps → sota-threat-modeling; leaked or mishandled credentials → sota-secrets- management. Pipeline/supply-chain → sota-devsecops; isolation blast-radius → sota- sandboxing.

3. Performance complaints about queries → start in sota-databases (EXPLAIN, indexes, N+1) before sota-performance (caching, I/O).

4. Anything realtime (websockets, SSE, pub/sub fanout) → sota-api-design rules/05 + sota- async-concurrency (backpressure).

5. AI/LLM features → sota-code-security rules/08 (prompt injection, tool authorization) + sota-sandboxing rules/05 (executing model output) + sota-databases rules/07 (vectors/RAG).

6. Frontend work → sota-frontend-design for design/UX/a11y/motion; sota-web-frameworks for React/Next or Vue/Nuxt engineering (RSC/client boundary, Server Actions, caching, hydration, SSR security); sota-javascript-typescript for the language/TS; sota-performance rules/06 for Web Vitals. A React/Next or Vue/Nuxt security review pulls all four.

7. Tests accompany everything. Any BUILD task that writes logic also loads sota-testing (strategy + design rules); any AUDIT includes a suite-health pass. Language-specific runner mechanics stay in the language skills.

8. LLM features split three ways. Quality/architecture → sota-llm-engineering; security (prompt injection, tool authz) → sota-code-security rules/08; executing model output → sota- sandboxing rules/05; PII in prompts/logs → sota-privacy-compliance.

9. Infra layers split four ways. Cloud-provider setup (accounts, VPC, compute, cost, DR) → sota-cloud-infrastructure; the Kubernetes platform itself (RBAC, admission, GitOps controllers, operators, etcd) → sota-kubernetes; pod/container/workload isolation mechanics → sota-sandboxing; CI/CD and supply chain → sota-devsecops. A K8s cluster audit loads sota- kubernetes + sota-network-security + sota-sandboxing.

10. Identity is its own layer. App-level login/session/JWT-validation code → sota-code-security rules/02 (authn), rules/17 (sessions/JWT), rules/03 (authz); identity infrastructure (IdP, OIDC/SAML config, RBAC/role-mapping design, provisioning, break-glass, SPIFFE) → sota-identity-access; the credentials themselves → sota-secrets-management.

11. Network: setup vs security. Cloud VPC/DNS/CDN provisioning → sota-cloud-infrastructure rules/03; segmentation, zero-trust, NetworkPolicy depth, service mesh/mTLS, egress/DNS/PKI posture → sota-network-security.

12. Prevention vs detection. Building the control → the relevant domain skill; verifying you'd catch the attack at runtime (logs, rules, hunting, IR) → sota-detection-engineering. Ops telemetry plumbing stays in sota-observability; design-time threat enumeration in sota- threat-modeling.

13. Ingesting untrusted/attacker-authored data (feeds, scraping, uploads, webhooks, RAG corpora, hostile parsers) → sota-code-security rules/09, with sota-sandboxing rules/04 for parser isolation. A tool ingesting whole repositories (scanner, SAST wrapper, review bot, agentic analyser) adds sota-sandboxing rules/05 §7 — staging, build execution, egress.

14. Data: OLTP vs analytics. App databases → sota-databases; pipelines, streaming, warehouse/lakehouse → sota-data-engineering; anything touching personal data → add sota- privacy-compliance.

15. Any handling of user/personal data (new fields, exports, logs, analytics, ML training) → check sota-privacy-compliance minimization and retention rules, even when the task isn't "about" privacy.

16. User-facing words split three ways. In-product UI text (labels, errors, empty states) → sota-ux-writing; marketing/site/email content → sota-copywriting; technical docs → sota- docs-workflow. The component patterns the text lives in stay sota-frontend-design.

17. Shell scripts hide everywhere — CI run blocks, Dockerfile RUN lines, Makefiles, entrypoints, and the one-liners you type to verify a claim: unlinted shell run against the system under test, which when wrong produces a false finding about the product (a usage error, exit 2, from the callee is the tell — but a failed glob is silent and fakes a clean result). Audit it all with sota-shell-scripting rules/01 §3 and rules/06, the file for pasted and agent-issued commands. And a script that produces or verifies evidence (attestations, ledgers, gate records, audit trails) is a security control written in shell: add sota-code-security rules/10, rules/12, rules/15 and, for a ledger or audit trail, rules/18.

18. Cryptography fans out — there is no single crypto skill (by design). Algorithm choice, AEAD/nonce discipline, CSPRNG, in-code key handling, TLS client config, crypto agility, and post-quantum migration → sota-code-security rules/04; constant-time comparison → rules/22; tamper-evident logs/audit ledgers (keyed hash chains, external anchoring, integrity-vs-completeness) → rules/18. The key material — storage backends (KMS/HSM, Vault, SOPS+age), lifecycle, rotation, per-credential-type handling → sota-secrets-management. Transport/PKI — TLS server config, cert lifecycle/ACME, private CA, mTLS → sota-network-security rules/06. FIPS-140-3-validated-module requirements → sota-security-compliance rules/02. Language- specific APIs (JCA, crypto/*, .NET) stay in the language skill. The stance throughout is use a vetted library, don't roll your own.

19. Which direction does the trust boundary point? Protecting the host from the workload (untrusted code, seccomp/microVMs/WASM sandboxes) → sota-sandboxing. Protecting the workload from the host/operator — TEEs (SEV-SNP/TDX/CCA/SGX), remote attestation, confidential VMs/containers, or computing on encrypted data (FHE/MPC/ZKP) → sota- confidential-computing. Both can apply to one system. Key custody/release stays sota- secrets-management; differential privacy and de-identification stay sota-privacy- compliance.

20. "It's enabled" is a claim, not a fact. Whenever a control's presence is established but its effect isn't — a banner, a config flag, a green test, "we have a scanner" — route to sota-code-security rules/10 (silent control failure). It pairs with sota-testing rules/06 (mutation-probe the control) and rules/09 (a security test must be watched to fail), sota- observability rules/05 (degradation must be visible), and sota-devsecops rules/04 (does the shipped artifact contain what the control needs at runtime?). Not for controls that are simply missing — that's the owning domain skill's audit checklist.

21. Model facts hide in your own tooling — the same shape as rule 17. Any question about a model's tokens, context window, pricing or limits is sota-llm-engineering (rules/02 §2 for counting, rules/05 for cost), including measuring your own files, prompts or docs, and even when the surrounding task is repo maintenance and nothing looks like an LLM feature. The tell is a chars/4 estimate or another vendor's tokenizer instead of the provider's count_tokens (measured 2026-08-26: 54% under).

Day zero — a repo this library has not been applied to yet

Installing is ambient: the rules apply in every directory, including a repo with no gates, no agent file and no LICENSE. They then govern the code you write and nothing else — the repo keeps accepting unscanned commits. Check this once per repo, on the first BUILD task in an unfamiliar one, by looking (not inferring): is there a .pre-commit-config.yaml or any other hook manager or CI job running a secret scan; a license file (LICENSE*, COPYING* or COPYRIGHT — never match the bare name, projects name it after the licence); an AGENTS.md/CLAUDE.md; and how long is the git history? Two or more missing and a history of a few commits = day zero. A long history means a mature repo that likely decided against them; say nothing.

When it fires, say it once, in a line, with the command, then get on with the task: scripts/init-gates.sh for gates — it installs both the pre-commit and pre-push hooks; a bare --hook-type pre-push would install only the latter (before the first commit, while a leaked credential is still free to remove), scripts/gen-agents-md.sh for the cross-tool entry point. Full ordering and reasoning — LICENSE, .gitignore, ambient-vs-repo-resident, the core.symlinks trap — in sota-docs-workflow rules/01 §10.

Offer, never perform. These write config into the user's repo. Mention once, act only on a yes, and treat a decline as decided.

BUILD mode — workflow

Reasoning and worked examples: rules/02-build-workflow.md. Changing a step below? It is mirrored in four places — rules/02 §5 lists them, and three fail silently.

1. Identify the domains the feature touches (table above) and the language(s).
2. Load lean. Read each relevant skill's SKILL.md and, from its index, open only the rules files that match the work. Lean costs less and measures no worse; the degradation this step once claimed is not supported — rules/02 §1. One rules file is not selected by subject. sota-shell-scripting **rules/06** governs the commands you type to check things — sweeps, counts, absence claims — and no task description ever matches it, because the task is never about checking. Load it on any task where you will verify a claim with a command, which is nearly all of them. Subject routing cannot reach it: cross-cutting rule 17 names it and still does not fire, because it reads as advice about where shell code hides in a repository rather than about your own next command. Field-reported twice, 2026-09-18 and 2026-09-21 — the second by a reader who had rule 17 in context.
3. Plan first, with the checks in the plan. Before writing code, list the task's requirements as concrete, checkable items — a specific outcome you can mark done/not-done ("rate-limit login to N/min per IP", not "add rate limiting") — covering the top-10 non-negotiables of each loaded skill plus operating principle 5. Vague items don't survive to step 4. Then implement against that list.
4. Self-audit gate (do this LAST — do not present code until it passes). First list the rules files step 2 loaded: none, or no sota-shell-scripting rules/06 when you verified by command, and this gate has FAILED — go back. Re-read each loaded rules file's Audit checklist and operating principle 5, and verify your diff satisfies every item. For each unmet item, implement it or state why it is out of scope — silence is not allowed. For every control, ask the falsification question: if this were silently a no-op, would anything observable differ? If nothing would — no log, no metric, no failing test — it is not done (sota-code-security rules/10). If the control emits an artifact, read back the one this run just produced. Doing this last is deliberate: a long context makes mid-context rules fade, and the final re-read is what recovers the rate limiting, transport, tests and logging a model otherwise drops — measured as the bulk of the library's completeness lift (evals/run-completeness.py). For a large build, run it as a separate pass over the diff, and push the few critical invariants into deterministic gates (rules/02 §3).

AUDIT mode — workflow

Procedure lives in two rules files, read together for any full audit: rules/01-audit-methodology.md (scoping, the verified tool matrix, triage, hygiene) and rules/03-audit-findings.md (severity — chain closure, the diff baseline — evidence, the decision ledger, refutation, the report template). A new pass needs a line in this router and a section in the rules file that owns it, never here.

For a focused audit, load the matching skills and follow their AUDIT sections. For a full project audit, work in passes:

1. Recon. Inventory languages, frameworks, entry points (HTTP routes, queues, cron, webhooks), data stores, CI config, Dockerfiles, IaC. This determines which skills apply; skip skills with no matching surface. Full procedure: rules/01 §2.
2. Threat model first. sota-threat-modeling rules/06 (reconstruction): assets, trust boundaries, entry points. Its output prioritizes the rest.
3. Per-domain passes. For each applicable skill, follow its AUDIT mode and audit checklists. Suggested order: secrets sweep (fast, high yield) → code security (incl. rules/09 untrusted-data ingestion) → language-specific (incl. shell scripts) → API → database → async/concurrency → identity & access → sandboxing/devsecops → kubernetes platform → network security → cloud infrastructure → privacy/compliance → architecture → testing suite health → performance → observability → detection-engineering posture → frontend/a11y → LLM features, data pipelines, mobile, CLI, docs as applicable. For an infrastructure/cluster audit the heavy hitters are sota-kubernetes, sota-network-security, sota-identity-access, sota-sandboxing and sota-detection-engineering.
4. Silent-control pass (always run it). The per-domain passes ask "is the control there?" — this one asks "does it do anything?", then "does it cover every site it is credited with?". Apply sota-code-security rules/10 (inert controls — invisible to the other passes and to SAST), sweeping with rules/11 first to find where to look: stage duration vs work claimed, every gate's denominator (0 checked, 0 failed, exit 0), size-gated paths no fixture crosses, cache keys narrower than the behaviour, one-sample parsers, assert-as-control. Then count: sota-code-security rules/14 §6 censuses what a working mitigation guards (9 of 61 is the finding), §7 falsifies the prose.
5. Decision-ledger review. Code passes find defects in what was built; they cannot find the defect where the code faithfully implements a choice that stopped being right — a store picked for scale that never arrived, an expired constraint still shaping the design. Reconstruct the expensive-to-reverse decisions (ADRs, design docs, CHANGELOG, the PRs behind each major component) and classify each JUSTIFIED / STALE / UNJUSTIFIED / UNVERIFIABLE. Where a decision rests on a number, re-measure it this session. Full procedure: rules/03 §3. Then ask where else the team's knowledge lives — an agent's private memory store, an IDE's notes, a chat log. Anything in there that is a fact about the repository with no home in the repository is a finding: invisible to review, absent from a fresh clone, gone when the store is cleared. It is an absence claim and the naive search for it lies — rules/01 §4a.
6. Findings. Emit every finding in the canonical cross-domain format (file:line | rule | severity | effort | fix) — skill-local formats are fine within a domain pass but must carry an effort field so the roll-up can be sequenced — deduplicate across domains, and roll up into the report structure from rules/03 §5. Severity: rules/03 §1 — a Critical/High names its chain, and a diff is rated against the code it replaced.
7. Refute before reporting. Re-reading your own finding re-runs the reasoning that produced it — it is the weakest check available. Every Critical/High gets an independent pass prompted to kill it (a separate agent, or a fresh-context hostile read), working from the code at the pinned commit rather than your write-up, defaulting to REFUTED when the evidence is ambiguous. Survivors ship; the rest are dropped or downgraded with the refutation recorded — and swept first: the refuted pattern routinely closes somewhere else, and that sweep is where the report's strongest finding comes from. Absence claims ("no X found") get a refuter too, and carry the heavier burden of principle 3. Full procedure and failure modes: rules/03 §4.

Library map (rules files per skill)

Which rules/NN file holds what, for all 43 skills (42 domain skills + this router): rules/04-library-map.md. Read it when you know the domain but not the file. When you are already opening a skill's SKILL.md (BUILD step 2), use that skill's own index instead — it carries the "read this when…" guidance the map drops.

What keeps a delivered audit report usable once remediation starts — reproduction steps on every finding, the finding lifecycle and retest, report provenance, verdicts that expire with their commit, and the three-run bar for "fixed": rules/05-audit-report-and-tracking.md, read with rules/03.

Context budget discipline

Rules files run 52–500 lines, median 262.5 (over all 294 on 2026-09-26; dated because the figure has gone stale before). So budget by the file you are actually opening, not by an average: 2–5 files is a typical focused task and can be 400 lines or 2,000. A full audit pass should load one skill at a time, finish its findings, then move on. If context is tight, prefer the skill's top-10 non-negotiables plus the single most relevant rules file.

When this library is wrong or missing something

These rules are maintained and measured, and they are still incomplete — the library has no telemetry and learns nothing from use unless someone says so. You are the only observer of the gap at the moment it appears.

If, while applying a skill, you hit one of these, say so in one line at the end of your answer and point the user at the report path — then carry on with the task:

• a rule contradicted by a primary source you just checked (version, spec, API, advisory) — freshness rot;
• a rule that does not fit the situation and states no exception for it;
• real surface area in the task with no owning skill — a routing gap;
• guidance that, followed literally, would have shipped a defect.

Two loaded rules that contradict each other are usually a scope collision: one is a general default, the other a requirement inside a narrower domain. The narrower wins in its domain — pick by which failure mode is worse here (a needless idiom vs an outage), never silently: name the rule you followed and why in a comment beside the code, or the next reader reverts it. Then report it — the fix is an explicit exception in whichever rule was too broad.

A routing gap should end as a test, not just a report: how, in rules/04, its last section.

Report: https://github.com/martinholovsky/SOTA-skills/issues/new/choose (bad-guidance / skill-request templates). Anything dangerous or security-sensitive goes to a private advisory instead — see SECURITY.md.

Do not fire this for personal preference, for a rule you simply did not need, or mid-task. One line, at the end, only when the library actually let the user down. An unreported gap stays in the library for everyone.