Legacy Audit

This audit determines which legacy material belongs in the Language Guide. Migration does not mean copying: each destination is rewritten against current syntax, sema, prelude signatures, and runtime tests.

Core language documents

Builtin documents

Data language

Historical application-system proposals

The following are useful design archives but do not correspond to current declaration kinds. They are summarized in feature status:

actor.md, actor-compare.md, context.md, guard.md, job.md, logger.md, messages.md, messaging.md, services.md, topic.md, workflows.md, and every file under docs/decorators/ (actors, ai, auth, data, events, fields, http, jobs, mcp, ui, and its index).

No example from those files is taught as current syntax merely because the generic decorator parser accepts its @name.

Compiler, IR, memory, and runtime material

These areas do not belong in the Language Guide:

• Every docs/compiler/*.md file is compiler architecture, planning, diagnostics, incremental compilation, debugging, reproducibility, or performance material.
• Every docs/design/*.md file is implementation design. async-system.md, select.md, and transactions.md were used as evidence for reader-visible semantics; their ABI and lowering detail remains outside the guide.
• arena.md, boxing-cleanup.md, flat.md, memory.md, docs/memory/*.md, and wasm_intrinsics_expansion_plan.md belong in the Runtime, MIR, or WasmIR sections. Only their source-visible guarantees were extracted.
• raft.md, docs/runtime/*.md, and docs/runtime/topics.md belong in runtime/distributed-system documentation.
• docs/host/host.md supplies host-binding and capability material; the decorator surface is in the guide, while ABI/adapter design belongs under Runtime.

Project tooling and repository notes

Every file under docs/project/ belongs under Start/Project Tooling rather than the Language Guide: atoll.toml.md, atoll.yaml.md, host.md, hot-deploy.md, project.md, serialization.md, sql.md, and tracing.md.

The meta and work-tracking files _assessment.md, _load.md, _presentation.md, _summary.md, _next/next.md, _next/perf.md, stashed_work_inventory.md, and compiler plan trackers remain contributor inputs, not reader chapters.

Rewrite rules applied

All migrated language material follows these rules:

1. Prefer current parser/sema tests and installed prelude stubs over prose.
2. Use lowercase scalar names, PascalCase composite names, square-bracket generics, snake_case members, and SCREAMING_SNAKE_CASE constants.
3. Replace let/var with immutable or mut := bindings.
4. Separate implemented, provisional, and historical behavior explicitly.
5. Keep ABI, continuation, reference-count, arena, and SQL executor details in technical-design sections unless they change the source-language contract.
6. Give every page one primary concept and a one-word title; use two words only when the established concept genuinely needs them.

Second review

A second implementation-led pass corrected several points that the legacy prose or first migration left ambiguous:

• string.length() counts Unicode code points, while string.len() counts UTF-8 bytes; byte_length() is only the deprecated compatibility alias.
• a parsed binding DATASOURCE := query prefix is not yet consumed by semantic routing, so named route overrides are marked provisional instead of taught as operational;
• Turso rejects FOR UPDATE rather than silently treating it as a no-op;
• race is first completion, not first success, and the current empty form still receives conservative static effects;
• DataFusion is a datasource query engine, while every Df[T] manipulation plan executes through Polars;
• frame, stream, task, file, socket, and transaction cleanup behavior was reconciled with current resource and cancellation tests.

These corrections illustrate why a destination is reanalyzed rather than copied from its source document.

Third review

A third source-and-test pass tightened contracts that were still broader than the implementation:

• struct construction currently type-checks supplied known fields but does not reliably reject missing, duplicate, or unknown fields, and parsed field defaults are not yet applied;
• binding type projections remove Result and then at most one supported Option or collection wrapper, with map projections selecting the value type;
• unannotated functions can synthesize a closed error union from several propagated error types;
• catch may recover to the success type, convert to a new Result error type, or leave directly through error; those outcomes are now documented separately;
• naming warnings are opt-in ATOLL7002 diagnostics, and their current AST coverage is narrower than the convention table in docs/code-style.md.

The Structs chapter is marked provisional until total construction checking and field-default lowering are implemented.