Runtime & Layout

Rezi's runtime turns state into frames through a deterministic pipeline. This page is an index for the runtime internals and the layout model used across widgets.

Runtime pipeline

Runtime phases

• Reconciliation: compares the new VNode tree to the previous one and computes changes.
• Layout: resolves sizes and positions in terminal cell units.
• Rendering: builds ZRDL drawlists and submits them to the backend.
• Event dispatch: parses ZREV batches and routes input to widgets or global handlers.

Layout model

Layout is cell-based and deterministic. Stacks (row, column) and constraints (width, height, flex) are the core primitives.

• Layout guide

Input & focus

Focus routing and key handling are part of the runtime contract.

• Input & focus
• Keyboard shortcuts recipe

Update contract

Update batching, commit points, and runtime error codes are defined in the lifecycle guide.

• Lifecycle & updates

Protocol boundary

The runtime talks to the engine over ZRDL and ZREV.

• Protocol overview
• Drawlists (ZRDL)
• Event batches (ZREV)