# Ultracite for Aider Use Ultracite with Aider when you want terminal pair programming to stay aligned with the same repo rules you expect from direct edits. It is a natural fit for patch-based workflows, quick iterations, and developer-in-the-loop collaboration. $ ## Setup details These values come from the same data Ultracite uses when it creates or updates Aider instructions, so the page matches what actually gets written into the repo. Run `npx ultracite@latest init --agents aider` and Ultracite will update this file for the default setup. ### Configuration file Ultracite writes to this exact file when you initialize or update the agent integration. ### Write mode Replace with a fresh rules file Ultracite writes a fresh rules file so the agent starts from a clean, predictable baseline. ### Header handling Writes rules directly The generated file starts directly with Ultracite rules and skips an extra heading block. ### Hook support No separate hook file Aider does not use a separate hook configuration in Ultracite. ## Files Ultracite writes for Aider This preview shows the exact default file content Ultracite writes for Aider when you use the standard Biome setup. ### Ultracite Code Standards This project uses **Ultracite**, a zero-config preset that enforces strict code quality standards through automated formatting and linting. #### Quick Reference - **Format code**: `npx ultracite fix` - **Check for issues**: `npx ultracite check` - **Diagnose setup**: `npx ultracite doctor` Biome (the underlying engine) provides robust linting and formatting. Most issues are automatically fixable. --- ## Core Principles Write code that is **accessible, performant, type-safe, and maintainable**. Focus on clarity and explicit intent over brevity. ### Type Safety & Explicitness - Use explicit types for function parameters and return values when they enhance clarity. - Prefer `unknown` over `any` when the type is genuinely unknown. - Use const assertions (`as const`) for immutable values and literal types. - Leverage TypeScript's type narrowing instead of type assertions. - Use meaningful variable names instead of magic numbers - extract constants with descriptive names. ### Modern JavaScript/TypeScript - Use arrow functions for callbacks and short functions. - Prefer `for...of` loops over `.forEach()` and indexed `for` loops. - Use optional chaining (`?.`) and nullish coalescing (`??`) for safer property access. - Prefer template literals over string concatenation. - Use destructuring for object and array assignments. - Use `const` by default, `let` only when reassignment is needed, never `var`. ### Async & Promises - Always `await` promises in async functions - don't forget to use the return value. - Use `async/await` syntax instead of promise chains for better readability. - Handle errors appropriately in async code with try-catch blocks. - Don't use async functions as Promise executors. ### React & JSX - Use function components over class components. - Call hooks at the top level only, never conditionally. - Specify all dependencies in hook dependency arrays correctly. - Use the `key` prop for elements in iterables (prefer unique IDs over array indices). - Nest children between opening and closing tags instead of passing as props. - Don't define components inside other components. - Use semantic HTML and ARIA attributes for accessibility: - Provide meaningful alt text for images - Use proper heading hierarchy - Add labels for form inputs - Include keyboard event handlers alongside mouse events - Use semantic elements (`