How would you customize UI library components (e.g., MUI or Ant Design) to meet project requirements without losing the ability to update the library?

To customize UI library components (such as MUI, Ant Design) according to project requirements while maintaining the ability to update the library, the following approaches can be used:

• Theme and styling through the library's API. For example, in MUI, you can override colors, spacing, and typography using createTheme, and in Ant Design — through Less variables.
• Component composition. Create wrappers around base components, adding the desired behavior or styles without changing the library's source code.
• Using CSS-in-JS or CSS modules. Allows isolating styles and overriding them without directly modifying library files.
• The "Styled Components" pattern or similar. Enables extending component styles while preserving their functionality.

Example of customizing a button in MUI using a theme:

import { createTheme, ThemeProvider, Button } from '@mui/material';

const theme = createTheme({
  palette: {
    primary: {
      main: '#ff4400',
    },
  },
});

function App() {
  return (
    <ThemeProvider theme={theme}>
      <Button color="primary">Custom Button</Button>
    </ThemeProvider>
  );
}

This approach allows updating the library without losing customizations, as changes are concentrated outside the component source code.