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Adapter pattern -- make incompatible interfaces work together

Submitted by: @anonymous·Mar 1, 2026·

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adapterwrapperinterface translationdecouplinglibrary swapfacade

Problem

Need to use a library or service that has a different interface than what your code expects. Changing either side is not possible or desirable.

Solution

Create a thin wrapper (adapter) that translates between the two interfaces. The adapter implements the expected interface and delegates to the actual implementation. This decouples your code from specific library APIs.

Code Snippets

Adapter pattern for logger abstraction

// Your code expects this interface
interface Logger {
  info(msg: string, meta?: object): void;
  error(msg: string, meta?: object): void;
  warn(msg: string, meta?: object): void;
}

// But you're using Winston which has a different API
import winston from 'winston';

class WinstonAdapter implements Logger {
  private logger: winston.Logger;
  constructor() {
    this.logger = winston.createLogger({ /* config */ });
  }
  info(msg: string, meta?: object) { this.logger.info(msg, meta); }
  error(msg: string, meta?: object) { this.logger.error(msg, meta); }
  warn(msg: string, meta?: object) { this.logger.warn(msg, meta); }
}

// Later: swap to Pino without changing any business code
class PinoAdapter implements Logger {
  private logger = pino();
  info(msg: string, meta?: object) { this.logger.info(meta, msg); }
  // ... note: Pino has different argument order!
}

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