Claude Skills by ericrisco

Use when writing, reviewing, testing, or shipping C# / .NET code — ASP.NET Core APIs (minimal APIs vs controllers), EF Core data access, async correctness, solution layout in .cs/.csproj/.sln. NOT a Java/Spring backend (that is spring-boot), NOT a Node/TypeScript backend (that is nestjs), NOT framework-neutral REST naming (that is api-design).

Use when a live support ticket needs triage (intent, P1–P4 priority, SLA clock), an on-voice reply, not a raw template, de-escalation of an angry or churn-risk customer, or escalation with a handoff packet. NOT the help-center article it links to (that is `technical-writing`), a win-back program (`retention`), or the auto-answer bot (`chatbot`).

Use when building or fixing a KPI dashboard decision-makers must read in one screen: which metrics earn a tile, how each tile is framed to answer a decision, and which chart fits it. NOT defining the metrics or their targets (that is kpi-framework), wiring the data (that is analytics), or writing a narrative status report (that is reporting).

Use when a raw table is too dirty to trust — nulls, sentinels, duplicate rows, category sprawl, mixed types, bad dates — and you need a re-runnable clean() plus a schema gate that fails loud. NOT emitting .xlsx (that is spreadsheet-ops), NOT acquiring rows (that is data-scraper), NOT parsing PDF/HTML into rows (that is structured-extraction).

Use when building internal data-governance machinery: a retention schedule (period, lawful basis, expiry action, system where deletion runs), an Art. 6 lawful-basis register, an Art. 30 ROPA, or a consent capture/withdrawal model. NOT the public privacy notice or DSAR handling (that is `gdpr-privacy`), NOT SOC 2 posture (that is `compliance`).

Use when data lives on a website with no usable API — listings, prices, public records — and the scrape must stay legal and not get blocked: legal gate, extraction path, durable selectors, pacing, resilience. NOT parsing bytes you already hold into fields (that is structured-extraction), NOT a documented API or key (that is api-connector-builder).

Use when a schema change must ship without downtime — NOT NULL, rename, type change, or backfilling millions of live rows — for the expand-contract sequence and the lock/batching discipline that keeps each step from freezing prod. NOT lock internals or EXPLAIN (that is `postgresdb`), NOT drizzle-kit mechanics (that is `drizzle-orm`), NOT PITR (that is `backups`).

Use when something is broken — a failing or flaky test, crash, wrong result or regression — and the root cause must be reproduced and proven before any fix. On-demand; callable mid-`implement`. NOT a feature to spec or build (that is `specify`/`implement`), NOT the lint/test gate (that is `verify`), NOT adversarial diff reading (that is `review`).

Use when a high-impact plan, migration or architecture claim needs a bounded adversarial challenge before commitment. Isolates claims from persuasion, attacks assumptions, reconciles doubts with evidence and emits proceed/hold/stop. NOT a finished-diff review (`review`/`code-review`), NOT SDD artifact consistency (`analyze`).

Use when a hard-to-reverse choice (database, framework, vendor, auth model) must be frozen as an immutable numbered ADR — the context that forced it, the options weighed, the decision, consequences both ways — or superseded without erasing history. NOT a meeting recap (that is meeting-notes), NOT standing project principles (that is constitution).

Use when training or debugging a neural net in PyTorch — the forward/loss/backward/step loop and its silent bugs, mixed precision (AMP), AdamW/LR schedules, DDP/FSDP/ZeRO, checkpoints and seeds. NOT LoRA/QLoRA on a pretrained LLM (that is `finetuning`), NOT tabular sklearn/XGBoost (that is `machine-learning`), NOT tokenization or NLP metrics (that is `nlp`).

Use when taking an app from source to live: choosing the deploy target from requirements (Hetzner+Coolify vs Vercel vs a third), then wiring container → CI → registry → host with build secrets, healthchecks and rollback. NOT one platform's mechanics (that is `coolify`, `vercel`, `railway`, `render`), NOT the Dockerfile alone (that is `docker`).

Use when retiring a public API, feature, integration, service or legacy path without abandoning consumers. Inventories usage, classifies advisory vs compulsory migration, ships compatibility/tooling, assigns owners and gates removal on evidence. NOT live schema expand-contract (`db-migrations`), NOT replacement API design (`api-design`).

Use when a design has won and its look must survive: codify it into a permanent style skill with measured ratios, bans and tests that can fail, then build new pieces in that exact look. Fires on 'turn this into a skill', 'keep the same style', 'my output drifted'. NOT finding the winner (that is `design-loop`), NOT the words (that is `marketing`).

Use when something must be built well and there is a real reference it should beat: turn what makes the reference good into measured mechanisms, then run a builder and three fresh-context critics until all three pass. Fires on 'design loop', 'make it as good as <site>', 'it looks generic'. NOT keeping an already-won look (that is `design-dna`).

Use when designing or refreshing a web UI or landing page — visual concept, type/color/spacing/motion tokens, composition, rescuing a UI that reads AI-generic, or a graded design review. Brand-grounded and research-first; ships Tailwind v4 + Next.js 15 under WCAG 2.2 AA and Core Web Vitals budgets. NOT the words on the page (that is `marketing`), NOT the App Router build (that is `nextjs`).

Use when deploying or operating a workload on DigitalOcean — Droplet vs App Platform vs Functions, doctl, app spec YAML, Managed Postgres/MySQL/Valkey on the VPC, S3-compatible Spaces + CDN. NOT host-agnostic CI/CD or rollback strategy (that is `deployment`), NOT a bare Hetzner VPS (that is `hetzner`), NOT another managed PaaS (that is `railway`).

Use when building, reviewing, securing, testing or shipping a Django app — models, migrations, QuerySets/managers, FBV/CBV views, forms, the admin, settings split, and Django REST Framework (serializers, ModelViewSet, permissions). NOT async FastAPI/Pydantic services (that is `fastapi`), NOT Postgres schema/index work (that is `postgresdb`).

Use when authoring or auditing a Dockerfile, shrinking a bloated image, hardening a container that runs as root, picking a base image, or wiring a Compose dev loop with hot reload. NOT CI builds or deploy-to-host (that is `deployment`), NOT k8s autoscaling (that is `scaling`), NOT app-level injection or secrets-in-code (that is `secure-coding`).

Use when the deliverable is a document's bytes or its literal content — text/tables out of PDFs, AcroForm fill and flatten, page merge/split, PDF/DOCX from templates, OCR of image-only scans. NOT schema-typed fields pulled from text (that is structured-extraction), NOT signature routing (e-signature) or spreadsheet cells/formulas (spreadsheet-ops).

Use when pointing a domain at a host or fixing broken HTTPS — delegating nameservers, writing A/AAAA/CNAME/ALIAS/MX/TXT/CAA rows, apex vs www, standing up auto-renewing TLS, and cutting nameservers over without downtime. NOT inbox placement or warmup (that is `email-deliverability`), NOT what runs behind the name (that is `deployment`).

Use when modeling data or querying with Drizzle ORM in TypeScript — `pgTable` schema in `.ts`, type-safe select/insert/relational queries, `drizzle-kit` migrations. NOT Prisma Client or `schema.prisma` (that is `prisma-orm`), NOT ORM-agnostic migration strategy (that is `db-migrations`), NOT Postgres engine tuning or EXPLAIN (that is `postgresdb`).

Use when analytical SQL must run in-process with no server: Parquet/CSV/JSON/Arrow queried in place, OLAP embedded in an app or notebook, a slow pandas groupby on multi-GB data, or S3/lakehouse data read without downloading. NOT a multi-user analytics server (that is clickhouse-analytics), NOT an app's transactional CRUD store (that is postgresdb).

Use when modeling or operating a DynamoDB table: deriving partition/sort keys from access patterns, single-table vs table-per-entity, adding a GSI/LSI, on-demand vs provisioned capacity, or diagnosing hot-partition throttling. NOT relational schema/SQL/EXPLAIN (that is `postgresdb`), NOT aggregation-pipeline document modeling (that is `mongodb`).

Use when wiring an e-signature flow with DocuSign or Dropbox Sign — picking the SES/AES/QES legal tier, sending a PDF or template for signature, embedded signing, verifying signing webhooks, retrieving the signed PDF plus audit trail. NOT drafting contract text (that is `contracts`), NOT extracting fields from PDFs (that is `document-processing`).

Use when writing or stabilizing Playwright tests that drive a real browser through multi-step journeys — durable locators, web-first assertions, storageState auth, trace/retries, and flakes that only bite in CI. NOT in-process component tests (that is testing-web), NOT WCAG auditing (that is accessibility), NOT the pre-merge gate (that is verify).

Use when building, hardening, or shipping a cross-platform Electron desktop app — main/renderer/preload process model, typed contextBridge IPC, locking down nodeIntegration/contextIsolation/sandbox/CSP, or packaging with signing and auto-update. NOT a Rust-backed shell on the native webview (that is tauri), nor the web UI inside it (that is react).

Use when a topic must be explained from zero to someone who knows nothing about it: one page, big pictures, very few words, everyday analogies, no jargon and nothing assumed. NOT the smallest in-conversation visual for someone already following (that is `show-me`), NOT a course with exercises (that is `course-builder`).

Use when writing or refactoring Elixir/OTP on the BEAM — GenServers, supervision trees and restart strategies, pattern matching, mix projects and releases — or when processes misbehave (restart loops, mailbox growth, call timeouts). NOT a Phoenix web app, LiveView, Ecto or channels (that is `phoenix`).

Use when wiring server code to send transactional or bulk email via Resend, SendGrid, or Postmark: a provider-agnostic sendEmail() seam, idempotent retries, 100-cap batches with partial failures, transactional-vs-broadcast streams, bounce webhooks feeding a suppression list. NOT SPF/DKIM/DMARC inbox reputation (that is `email-deliverability`).

Use when mail already sent lands in spam, is rejected, or fails the Gmail/Yahoo bulk-sender checks and the fix is authentication and reputation, not the sending code: SPF/DKIM/DMARC alignment, domain warmup, spam-complaint rate, one-click unsubscribe, BIMI. NOT putting mail on the wire through a provider API (that is `email-connector`).

Use when choosing an embedding model, chunk size, or query form, when semantic search returns irrelevant results, when adding hybrid BM25+vector or a reranker, or when a retrieval change needs a number (recall@k, nDCG, MRR). NOT operating the store — index tuning, quantization (that is `vector-db`) — nor the retrieve-to-answer loop (that is `rag`).

Use when designing the reaction to a class of failures — typed error taxonomies, retry/backoff/timeout policy, circuit breakers, React/Next error boundaries, and the user-message vs operator-log split. NOT diagnosing one specific crash (that is debug), NOT logs/metrics/traces (that is observability), NOT the wire error envelope (that is api-design).

Use when shipping a React Native app with Expo — EAS Build/Submit/Update, eas.json profiles and channels, config plugins, prebuild/CNG, runtime-version policy, OTA updates that never land, SDK upgrades, the New Architecture. NOT RN UI, navigation or native-module authoring (that is `react-native`), NOT a Dart app (that is `flutter`).

Use when a substantive request needs verified, calibrated reasoning — analysis, diagnosis, review, advice, or a draft the user will act on — even when rigor is not asked for, and most of all when being wrong is expensive or irreversible. NOT casual chat (rigor theater), NOT the SDD gates `verify`, `debug`, `review`; this is the discipline beneath them.

Use when calling a fal.ai endpoint by id to generate image, audio, or video from JS/Python/curl: subscribe vs submit, queue states, ED25519 webhook signature verification, per-call cost, or migrating off @fal-ai/serverless-client. NOT which model or art direction (that is ai-media); NOT the same models on another platform (that is replicate).

Use when building, reviewing, testing, securing or shipping a FastAPI / async Python service — routers, Pydantic v2 schemas, dependency injection, async SQLAlchemy 2.0, OAuth2/JWT, ASGITransport tests, production wiring. NOT language-level Python or packaging (that is `python`), NOT engine-level SQL (that is `postgresdb`), NOT framework-agnostic REST contracts (that is `api-design`).

Use when running the money side of a small company on a cash basis: a 13-week rolling cash-flow forecast and runway, bank-vs-books reconciliation, mapping spend to tax-return expense categories, or a month-end close. NOT posting journal entries, payroll or depreciation (that is `bookkeeping`); NOT multi-year projections (that is `financial-model`).

Use when a founder needs the driver-based 18–36 month projection: revenue, cost and headcount builds resolving to net burn, runway, cash-out date, scenarios and the raise size. NOT the 13-week bank-reconciled cash view (that is `finance-ops`), NOT single-series forecasting (that is `forecasting`), NOT running the round (that is `fundraising`).

Use when adapting an open-weight model to a target form or behavior — tone, output format, reasoning pattern — via LoRA/QLoRA or full fine-tuning with TRL SFTTrainer, then preference optimization (DPO/ORPO/KTO/GRPO), and for fine-tune vs prompt vs RAG. NOT adding facts to a model (that is rag); NOT the single-GPU Unsloth backend or GGUF export (that is unsloth).

Use when building on Firebase — Firestore data modeling, Security Rules, Auth and custom claims, Cloud Functions, Storage, modular Web/Admin SDK imports — including symptoms like a database open to the internet, a query rejected by rules, or a doc stuck at ~1 write/sec. NOT managed-Postgres BaaS with SQL and RLS (that is supabase).

Use when building, structuring, testing or optimizing a Flutter app — feature-first layering, Riverpod 3 or Bloc, typed go_router, freezed models, a dio data layer, Material 3, jank hunting, widget/golden tests. Targets Flutter 3.44 / Dart 3.12. NOT React Native (that is `react-native`), NOT Compose Multiplatform (that is `compose-multiplatform`).

Use when deploying or operating an app on Fly.io — writing fly.toml, placing Machines in regions near users, attaching Volumes, managing secrets, or picking a scaling lever (autostop/autostart, scale count, fly-replay). NOT choosing which host to deploy on (that is `deployment`), NOT a git-push PaaS with no regions model (that is `railway`).

Use when projecting history forward — sales, demand, units, revenue, signups, traffic — into a defensible number with an error band: method by data shape, rolling-origin backtest, MASE vs the naive baseline. NOT an assumption-driven P&L or runway model (that is `financial-model`), NOT sizing reorder points or safety stock (that is `inventory`).

Use when planning or running an equity round as a process: sizing the raise to a milestone, choosing post-money SAFE vs priced round, tiering investors by intro path, sequencing outreach for momentum, or reading a term sheet before signing. NOT the slide narrative (that is `pitch-deck`), NOT the cap-table or valuation math (that is `financial-model`).

Use when designing or repairing what makes a game fun — verbs and mechanics, moment-to-moment/session/meta loops, progression, economy faucets and sinks, difficulty curves, dominant strategies, juice, prototyping and scope. NOT engine code (that is `godot`), NOT story (that is `game-storytelling`), NOT level layout (that is `level-design`).

Use when a game's story is the work: premise and pillars, branching topology, meaningful choice, dialogue state, quests, environmental storytelling, ludonarrative harmony. Author portable — engine wiring is `godot`/`unity`/`unreal`. NOT the mechanics and economy the story serves (that is `game-design`), NOT level layout (that is `level-design`).

Use when adding multiplayer or netcode to a game — client-server vs P2P, server authority and anti-cheat, state replication vs RPCs, prediction and reconciliation, lag compensation, plus Godot 4 / Unity NGO / Unreal wiring. NOT single-player gameplay (that is `godot`, `unity`, `unreal`), NOT matchmaking or server hosting (that is `deployment`).

Use when making NPCs, enemies, or units navigate a level — grid vs waypoint vs navmesh, A*/JPS, navmesh baking and agent radius, off-mesh links, steering, RVO crowd avoidance, and flow fields in Godot 4.x, Unity, Unreal. NOT collision response or character controllers (that is gamedev-physics), NOT aggro or difficulty design (that is game-design).

Use when working with a game engine's physics — rigid bodies, colliders, collision layers and masks, character controllers, joints, forces versus impulses, raycasts and shapecasts, or when a simulation is unstable (tunnelling, jitter, missed overlaps). Covers the Godot, Unity and Unreal equivalents. NOT rendering or shader-driven visual jitter (that is `gamedev-shaders`), NOT navigation, pathfinding or navmesh (that is `gamedev-pathing`).