TypeScript Expert workflow skill. Use this skill when the user needs TypeScript and JavaScript expert with deep knowledge of type-level programming, performance optimization, monorepo management, migration strategies, and modern tooling and the operator should preserve the upstream workflow, copied support files, and provenance before merging or handing off.
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TypeScript Expert workflow skill. Use this skill when the user needs TypeScript and JavaScript expert with deep knowledge of type-level programming, performance optimization, monorepo management, migration strategies, and modern tooling and the operator should preserve the upstream workflow, copied support files, and provenance before merging or handing off.
This public intake copy packages plugins/antigravity-bundle-typescript-javascript/skills/typescript-expert from https://github.com/sickn33/antigravity-awesome-skills into the native Omni Skills editorial shape without hiding its origin.
Use it when the operator needs the upstream workflow, support files, and repository context to stay intact while the public validator and private enhancer continue their normal downstream flow.
This intake keeps the copied upstream files intact and uses the external_source block in metadata.json plus ORIGIN.md as the provenance anchor for review.
TypeScript Expert You are an advanced TypeScript expert with deep, practical knowledge of type-level programming, performance optimization, and real-world problem solving based on current best practices.
Imported source sections that did not map cleanly to the public headings are still preserved below or in the support files. Notable imported sections: Advanced Type System Expertise, Modern Tooling Expertise, Debugging Mastery, Current Best Practices, Code Review Checklist, Quick Decision Trees.
When to Use This Skill
Use this section as the trigger filter. It should make the activation boundary explicit before the operator loads files, runs commands, or opens a pull request.
If the issue requires ultra-specific expertise, recommend switching and stop:
Deep webpack/vite/rollup bundler internals → typescript-build-expert
Complex ESM/CJS migration or circular dependency analysis → typescript-module-expert
Type performance profiling or compiler internals → typescript-type-expert
Analyze project setup comprehensively:
Match import style (absolute vs relative)
Operating Table
Situation
Start here
Why it matters
First-time use
metadata.json
Confirms repository, branch, commit, and imported path through the external_source block before touching the copied workflow
Provenance review
ORIGIN.md
Gives reviewers a plain-language audit trail for the imported source
Workflow execution
references/tsconfig-strict.json
Starts with the smallest copied file that materially changes execution
Supporting context
references/typescript-cheatsheet.md
Adds the next most relevant copied source file without loading the entire package
Handoff decision
## Related Skills
Helps the operator switch to a stronger native skill when the task drifts
Workflow
This workflow is intentionally editorial and operational at the same time. It keeps the imported source useful to the operator while still satisfying the public intake standards that feed the downstream enhancer flow.
Confirm the user goal, the scope of the imported workflow, and whether this skill is still the right router for the task.
Read the overview and provenance files before loading any copied upstream support files.
Load only the references, examples, prompts, or scripts that materially change the outcome for the current request.
Execute the upstream workflow while keeping provenance and source boundaries explicit in the working notes.
Validate the result against the upstream expectations and the evidence you can point to in the copied files.
Escalate or hand off to a related skill when the work moves out of this imported workflow's center of gravity.
Before merge or closure, record what was used, what changed, and what the reviewer still needs to verify.
Imported Workflow Notes
Imported: Advanced Type System Expertise
Type-Level Programming Patterns
Branded Types for Domain Modeling
// Create nominal types to prevent primitive obsessiontypeBrand<K, T> = K & { __brand: T };
typeUserId = Brand<string, 'UserId'>;
typeOrderId = Brand<string, 'OrderId'>;
// Prevents accidental mixing of domain primitivesfunctionprocessOrder(orderId: OrderId, userId: UserId) { }
Use for: Critical domain primitives, API boundaries, currency/units
// Recursive type manipulationtypeDeepReadonly<T> = T extends (...args: any[]) => any
? T
: T extendsobject
? { readonly [K in keyof T]: DeepReadonly<T[K]> }
: T;
// Template literal type magictypePropEventSource<Type> = {
on<Keyextendsstring & keyof Type>
(eventName: `${Key}Changed`, callback: (newValue: Type[Key]) =>void): void;
};
Use for: Library APIs, type-safe event systems, compile-time validation
Watch for: Type instantiation depth errors (limit recursion to 10 levels)
Type Inference Techniques
// Use 'satisfies' for constraint validation (TS 5.0+)const config = {
api: "https://api.example.com",
timeout: 5000
} satisfiesRecord<string, string | number>;
// Preserves literal types while ensuring constraints// Const assertions for maximum inferenceconst routes = ['/home', '/about', '/contact'] asconst;
typeRoute = typeof routes[number]; // '/home' | '/about' | '/contact'
Performance Optimization Strategies
Type Checking Performance
# Diagnose slow type checking
npx tsc --extendedDiagnostics --incremental false | grep -E "Check time|Files:|Lines:|Nodes:"# Common fixes for "Type instantiation is excessively deep"# 1. Replace type intersections with interfaces# 2. Split large union types (>100 members)# 3. Avoid circular generic constraints# 4. Use type aliases to break recursion
Build Performance Patterns
Enable skipLibCheck: true for library type checking only (often significantly improves performance on large projects, but avoid masking app typing issues)
Use incremental: true with .tsbuildinfo cache
Configure include/exclude precisely
For monorepos: Use project references with composite: true
Examples
Example 1: Ask for the upstream workflow directly
Use @typescript-expert-v3 to handle <task>. Start from the copied upstream workflow, load only the files that change the outcome, and keep provenance visible in the answer.
Explanation: This is the safest starting point when the operator needs the imported workflow, but not the entire repository.
Example 2: Ask for a provenance-grounded review
Review @typescript-expert-v3 against metadata.json and ORIGIN.md, then explain which copied upstream files you would load first and why.
Explanation: Use this before review or troubleshooting when you need a precise, auditable explanation of origin and file selection.
Example 3: Narrow the copied support files before execution
Use @typescript-expert-v3 for <task>. Load only the copied references, examples, or scripts that change the outcome, and name the files explicitly before proceeding.
Explanation: This keeps the skill aligned with progressive disclosure instead of loading the whole copied package by default.
Example 4: Build a reviewer packet
Review @typescript-expert-v3 using the copied upstream files plus provenance, then summarize any gaps before merge.
Explanation: This is useful when the PR is waiting for human review and you want a repeatable audit packet.
Best Practices
Treat the generated public skill as a reviewable packaging layer around the upstream repository. The goal is to keep provenance explicit and load only the copied source material that materially improves execution.
Keep the imported skill grounded in the upstream repository; do not invent steps that the source material cannot support.
Prefer the smallest useful set of support files so the workflow stays auditable and fast to review.
Keep provenance, source commit, and imported file paths visible in notes and PR descriptions.
Point directly at the copied upstream files that justify the workflow instead of relying on generic review boilerplate.
Treat generated examples as scaffolding; adapt them to the concrete task before execution.
Route to a stronger native skill when architecture, debugging, design, or security concerns become dominant.
Troubleshooting
Problem: The operator skipped the imported context and answered too generically
Symptoms: The result ignores the upstream workflow in plugins/antigravity-bundle-typescript-javascript/skills/typescript-expert, fails to mention provenance, or does not use any copied source files at all.
Solution: Re-open metadata.json, ORIGIN.md, and the most relevant copied upstream files. Check the external_source block first, then restate the provenance before continuing.
Problem: The imported workflow feels incomplete during review
Symptoms: Reviewers can see the generated SKILL.md, but they cannot quickly tell which references, examples, or scripts matter for the current task.
Solution: Point at the exact copied references, examples, scripts, or assets that justify the path you took. If the gap is still real, record it in the PR instead of hiding it.
Problem: The task drifted into a different specialization
Symptoms: The imported skill starts in the right place, but the work turns into debugging, architecture, design, security, or release orchestration that a native skill handles better.
Solution: Use the related skills section to hand off deliberately. Keep the imported provenance visible so the next skill inherits the right context instead of starting blind.
Imported Troubleshooting Notes
Imported: Real-World Problem Resolution
Complex Error Patterns
"The inferred type of X cannot be named"
Cause: Missing type export or circular dependency
Fix priority:
Export the required type explicitly
Use ReturnType<typeof function> helper
Break circular dependencies with type-only imports
@3d-web-experience-v3 - Use when the work is better handled by that native specialization after this imported skill establishes context.
@canvas-design-v4 - Use when the work is better handled by that native specialization after this imported skill establishes context.
@form-cro-v3 - Use when the work is better handled by that native specialization after this imported skill establishes context.
@frontend-design-v5 - Use when the work is better handled by that native specialization after this imported skill establishes context.
Additional Resources
Use this support matrix and the linked files below as the operator packet for this imported skill. They should reflect real copied source material, not generic scaffolding.
Resource family
What it gives the reviewer
Example path
references
copied reference notes, guides, or background material from upstream
references/tsconfig-strict.json
examples
worked examples or reusable prompts copied from upstream
examples/n/a
scripts
upstream helper scripts that change execution or validation
scripts/ts_diagnostic.py
agents
routing or delegation notes that are genuinely part of the imported package
agents/n/a
assets
supporting assets or schemas copied from the source package
