Implementation Notes

This chapter is written for developers working on the library itself. It provides technical background information about internal implementation details, code structure, and platform-specific behavior that are intentionally not part of the public API documentation.

For the stable public backend contract and custom-backend extension points, see Backend.

Use these notes when you want to:

  • extend or adapt an existing backend

  • debug platform-specific integration issues

  • understand where a specific low-level responsibility is implemented

  • explore the design decisions behind core components

Important

The pages in this chapter describe internal behavior and design decisions intended for contributors and maintainers. If you are using the library in an application, start with the usage guides and API reference instead.

Windows Backend

Follow how the Windows console is initialized, how key input is processed, how the screen size is detected, and how termination state is restored.

Windows Backend
POSIX Backend

Explore the POSIX terminal setup, raw key input handling, TTY probing, and the pipe-based signal forwarding mechanism.

POSIX Backend
Paragraph Layout and Painting

Trace how paragraphs are tokenized, wrapped into physical lines, and finally painted into terminal buffers.

Paragraph Layout and Painting
Unicode Width System

Understand how the Unicode width table is generated, queried, and consistently applied during terminal layout.

Unicode Width System