_spec-template.md

title	<short, descriptive title>
document_id	<stable-id, e.g., subsystem-YYYY-MM-DD>
status	draft
created	<UTC ISO-8601>
last_updated	<UTC ISO-8601>
version	0.1.0
engine_workspace_version	2023.1.30
wgpu_version	26.0.1
shader_backend_default	naga
winit_version	0.29.10
repo_commit	<git sha at update>
owners	lambda-sh
reviewers	engine rendering
tags	spec <area>

Note: Place specifications under the appropriate area folder (for example, docs/specs/rendering/) and add them to docs/specs/README.md.

Summary

• State the problem and the desired outcome in one paragraph.
• Include a concise rationale for introducing or changing behavior.

Scope

• Goals
  • List concrete, testable goals.
• Non-Goals
  • List items explicitly out of scope.

Terminology

• Define domain terms and acronyms on first use (for example, uniform buffer object (UBO)). Use the acronym thereafter.

Architecture Overview

• Describe components, data flow, and boundaries with existing modules.
• Include a small ASCII diagram if it materially aids understanding.

Design

• API Surface
  • Enumerate public types, builders, functions, and commands.
  • Use code identifiers with backticks (for example, RenderCommand).
• Behavior
  • Specify observable behavior, constraints, and edge cases.
  • Use normative language (MUST/SHOULD/MAY) where appropriate.
• Validation and Errors
  • Document validation rules and the layer that enforces them.
  • Describe error conditions and error types.

Constraints and Rules

• Platform and device limits that apply (for example, alignments, size caps).
• Data layout or serialization rules, if any.

Performance Considerations

• Recommendations
  • State performance guidance succinctly.
  • Rationale: Provide a short reason for each recommendation.

Requirements Checklist

• Functionality
  • Feature flags defined (if applicable)
  • Core behavior implemented
  • Edge cases handled (list)
• API Surface
  • Public types and builders implemented
  • Commands/entry points exposed
  • Backwards compatibility assessed
• Validation and Errors
  • Input validation implemented
  • Device/limit checks implemented
  • Error reporting specified and implemented
• Performance
  • Critical paths profiled or reasoned
  • Memory usage characterized
  • Recommendations documented
• Documentation and Examples
  • User-facing docs updated
  • Minimal example(s) added/updated
  • Migration notes (if applicable)

For each checked item, include a reference to a commit, pull request, or file path that demonstrates the implementation.

Verification and Testing

• Unit Tests
  • Describe coverage targets and representative cases.
  • Commands: cargo test -p <crate> -- --nocapture
• Integration Tests
  • Describe scenarios and expected outputs.
  • Commands: cargo test --workspace
• Manual Checks (if necessary)
  • Short, deterministic steps to validate behavior.

Compatibility and Migration

• Enumerate breaking changes and migration steps, or state “None”.
• Note interactions with feature flags or environment variables.

Changelog

• (v0.1.0) — Initial draft.