🎯

noimplicitany-completion

🎯Skill

from marius-townhouse/effective-typescript-skills

What it does

Eliminates implicit `any` types during TypeScript migration, enforcing strict type safety and completing the adoption process.

📦

Part of

marius-townhouse/effective-typescript-skills(83 items)

noimplicitany-completion

Installation

Quick InstallInstall with npx

npx skills add marius-townhouse/effective-typescript-skills --all

Quick InstallInstall with npx

npx skills add marius-townhouse/effective-typescript-skills -s prefer-unknown-over-any exhaustiveness-checking

Quick InstallInstall with npx

npx skills add marius-townhouse/effective-typescript-skills -a opencode claude-code

Quick InstallInstall with npx

npx skills add marius-townhouse/effective-typescript-skills -l

git cloneClone repository

git clone https://github.com/marius-townhouse/effective-typescript-skills.git

📖 Extracted from docs: marius-townhouse/effective-typescript-skills

Need more details? View full documentation on GitHub →

1Installs

AddedFeb 4, 2026

View on GitHub Back to Skills

Skill Details

SKILL.md

Use when finishing TypeScript migration. Use when enabling strict mode. Use when finalizing tsconfig. Use when ensuring type safety. Use when completing adoption.

Overview

# Don't Consider Migration Complete Until You Enable noImplicitAny

Overview

noImplicitAny is the cornerstone of TypeScript's type safety. When disabled, TypeScript silently gives variables the any type when it can't infer a type. This defeats the purpose of TypeScript. Don't consider your migration complete until you've enabled noImplicitAny and eliminated all implicit anys.

When to Use This Skill

Finishing TypeScript migration
Enabling strict mode
Finalizing tsconfig configuration
Ensuring type safety
Completing TypeScript adoption

The Iron Rule

Enable noImplicitAny to complete your TypeScript migration. Eliminate all implicit anys for full type safety.

Example

```typescript

// With noImplicitAny: false (default during migration)

function parse(data) {

// data is implicitly any - no error!

return data.json();

}

// With noImplicitAny: true

function parse(data) {

// Error: Parameter 'data' implicitly has an 'any' type

return data.json();

}

// Fixed with explicit type

function parse(data: string): unknown {

return JSON.parse(data);

}

```

Enabling Strict Mode

```json

{

"compilerOptions": {

"noImplicitAny": true,

"strictNullChecks": true,

"strictFunctionTypes": true,

"strictBindCallApply": true,

"strictPropertyInitialization": true,

"noImplicitThis": true,

"alwaysStrict": true

}

```

Reference

Effective TypeScript, 2nd Edition by Dan Vanderkam
Item 83: Don't Consider Migration Complete Until You Enable noImplicitAny

More from this repository10

🎯

tsdoc-comments🎯Skill

Generates TypeScript documentation comments (TSDoc) to explain public APIs, complex types, and provide comprehensive code documentation with IDE tooltips.

🎯

async-over-callbacks🎯Skill

Transforms callback-based asynchronous code into clean, readable async/await patterns for better type flow and error handling.

🎯

type-safe-monkey-patching🎯Skill

Enables type-safe runtime extension of global objects and DOM elements in TypeScript without sacrificing type checking or using `as any`.

🎯

create-objects-all-at-once🎯Skill

Efficiently initializes multiple TypeScript objects simultaneously using concise object literal syntax and spread operators.

🎯

module-by-module-migration🎯Skill

Guides developers through systematic TypeScript module migration, breaking down complex refactoring into manageable, incremental steps.

🎯

ts-js-relationship🎯Skill

Explains TypeScript's relationship to JavaScript, highlighting how it adds static typing and catches errors before runtime while remaining fully compatible with JavaScript code.

🎯

code-gen-independent🎯Skill

Generates JavaScript code despite TypeScript type errors and demonstrates that TypeScript types are erased at runtime, requiring alternative type checking strategies.

🎯

context-type-inference🎯Skill

Helps restore precise type context when extracting values, preventing type inference errors through annotations, const assertions, and type preservation techniques.

🎯

precise-string-types🎯Skill

Enforces strict string type constraints and prevents unintended string type conversions in TypeScript projects.

🎯

type-display-attention🎯Skill

Displays and simplifies complex TypeScript types to improve IDE readability and developer experience.