Focuses on type scale, spacing, sizing, variable fonts, OpenType features, wrapping, truncation and other details that make typography feel great across your product.

Helps with grouping, alignment, reading order, progressive disclosure and other details that make a good layout.

Helps your project comply with accessibility standards and best practices.

Safely modifies Xcode projects (.pbxproj) to add Swift Packages and link files. Use this skill whenever an iOS project needs dependencies installed (e.g. Firebase, Alamofire).

Designs, authors, refactors, and hardens production-grade Cloud Firestore Security Rules (firestore.rules). IMPORTANT: If subagent delegation AND the firestore-rules-author subagent are available in your environment, delegate authoring firestore.rules to the firestore-rules-author subagent. If subagent delegation is unavailable (e.g. not enabled in the IDE), firestore-rules-author is not installed, or you are running inside firestore-rules-author, follow this skill directly.

Audits Firebase (Firestore, Cloud Storage) security rules for vulnerabilities, privilege escalation, role bypasses, create vs update inconsistencies, resource exhaustion, type safety, size limits, and hasOnly ownership checks. Use when auditing/reviewing rules, running red-team rule assessments, or scoring against auditor checklists. Don't use for Firebase CLI (login, deploy), Auth, Crashlytics, Remote Config, or database queries.

Manages Firebase Remote Config templates, feature flags, loading strategies, and SDKs (Android, iOS). Use when downloading/deploying remoteconfig JSON templates, managing version history/feature flags, setting in-app defaults, fetchAndActivate(), real-time listeners, or SDK setup. Don't use for Firebase Hosting, Auth, Firestore, Data Connect, Crashlytics, or App Hosting.

Sets up, manages, queries, and configures Cloud Firestore databases (Standard/Enterprise edition), including data modeling, security rules, indexes, and SDK integrations (Web, Python, iOS, Android, Flutter). Use when creating/listing Firestore databases, defining data models/indexes, writing SDK queries, or integrating Firestore SDKs. For authoring or modifying Firestore Security Rules (firestore.rules), delegate to the firestore-rules-author subagent if subagent delegation is available, or use firestore-rules-creation otherwise. Don't use for Firebase Hosting, Data Connect, Auth, Storage/GCS, Crashlytics, Functions, or BigQuery.

Builds and deploys Firebase SQL Connect (aka Firebase Data Connect) backends with PostgreSQL securely. Use when designing schemas with tables and relations, writing authorized queries and mutations, configuring real-time data updates, or generating type-safe SDKs. Use when you need a relational database with Firebase, or when the user mentions SQL Connect or Data Connect.

Comprehensive guide for Firebase Crashlytics, including provisioning and SDK usage. Use this skill when the user needs help setting up Crashlytics, adding crash reporting, or using the Crashlytics SDK in their application.

Provides foundational Firebase CLI setup, CLI installation, version checks (`firebase-tools@latest --version`), CLI login (including --no-localhost), project creation, project selection (`firebase use`), and app config file downloads (`google-services.json`, `GoogleService-Info.plist`). Use ONLY for CLI login, project creation/switching, or downloading app config files. Don't use for Firebase Hosting deploy, Firestore, Auth, App Hosting, Data Connect, Crashlytics, or Remote Config.

Guide for setting up and using Firebase Authentication. Use this skill when the user's app requires user sign-in, user management, or secure data access using auth rules.

Fastly traffic numbers: cache hit ratio, bandwidth, request counts, status-code and error rates, edge vs origin traffic, real-time requests-per-second, origin latency, per-domain traffic, account usage and billing totals. Owns the `fastly stats` CLI commands and the Historical Stats, Real-Time and Origin/Domain Inspector HTTP APIs. Use for any question that needs a number about how a Fastly service is performing or how much it is being used.

Curated GitHub repositories demonstrating working reference architectures on the Fastly platform, from single Compute applications to systems combining multiple Fastly products. Use when designing a new solution on Fastly and a worked example of the target pattern would help, or when implementing and a concrete assembled reference would clarify the shape of the code. Not for documentation of how a specific Fastly tool or API works on its own — see the tool-specific skills for that.

Use when testing VCL against real Fastly edge infrastructure, writing assertion-based Fiddle tests, producing shareable fiddle URLs for bug reproductions, running VCL integration tests in CI, linting VCL remotely via the Fiddle API, or working with clientFetch/events/originFetches test expressions.

Build or modify manifest-backed IWSDK UIKitML with bounded preview, placement, and runtime verification. Use for spatial panels, browser HUDs, UIKitML layout, fonts, editor previews, and runtime element behavior.

Verify ray clicks, UIKit selections, and DistanceGrabbable interactions with emulated XR controllers. Use for pointing, selecting, pressing spatial UI, or moving an object through a distance grab.

Ship an IWSDK app to Meta Quest and the Horizon Store as a PWA/TWA — both immersive WebXR and 2D windowed panel modes. Use for PWA packaging, web app manifest and icons, auto-enter-XR on launch, bubblewrap APK builds, signing keystores, Digital Asset Links, sideloading, and Horizon Store upload. Also use when a packaged app is stuck loading, shows a URL bar, or will not launch.

Test an IWSDK app in a real Quest immersive session while controlling headset and controller poses through the IWSDK CLI. Use when the user asks to run, automate, or debug an app on a connected Quest rather than in desktop IWER emulation.

Add or repair IWSDK rigid-body simulation, collision shapes, forces, and physics-aware grabbing. Use for gravity, falling, collision, bouncing, kinematic motion, or physics tuning.