design

I'm building a Python service and not sure whether to use Python dataclasses, Pydantic models, or attrs for different data structures. I need to understand the tradeoffs for API schemas, internal data...

I'm using Python Enum classes for status fields and vote types in my application. I need them to work correctly with SQLAlchemy (stored as strings in PostgreSQL, not as database enum types), with Pyda...

I have API call state with loading, success, and error variants. Using optional fields allows impossible states. I want discriminated unions with full TypeScript narrowing.

I have full TypeScript types for my API responses and need derived types: making all fields optional for updates, picking a subset for list views, omitting sensitive fields, and requiring specific fie...

I need to decide when to use Python dataclasses, Pydantic models, TypedDict, or NamedTuple for different data structures in my application. Each has tradeoffs in validation, serialization, and overhea...

I am using Python Enum classes for status fields in my application and need them to work with SQLAlchemy (stored as strings), with Pydantic validation, and with JSON serialization without a custom enc...

I enabled TypeScript strict mode and now have many type errors. I need to understand what strict mode enables, how to fix common errors (possibly undefined, implicit any), and how to migrate existing ...

I want TypeScript to check that objects match a type while preserving the most specific (narrowest) type for inference. I also want const objects with literal types not broadened to string.

I need to extend types from a third-party library (fastify, express, next.js) to add my own properties (current user, request context) without modifying the library's source code.

I have Python code using os.path and string concatenation for file paths that breaks on Windows. I need to use pathlib for cross-platform file operations that work on Linux, macOS, and Windows.

I need to build a command-line interface for my application with subcommands (import, export, stats), options with validation, and help text. I want it to be testable and support both interactive and ...

I am using Python dataclasses for internal data objects. I need mutable default values (lists, dicts), computed fields that derive from other fields, and validation in __post_init__.

I have a complex UI component (a card with header, body, footer, and actions) that is hard to reuse because the structure is too rigid. I want a flexible composition pattern that lets callers customiz...