rust-coder

1# Rust Coder
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3Implement directly in the current Codex session. Do not launch another Codex process.
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5Read [references/standards.md](references/standards.md) completely before editing. Repository instructions and the declared toolchain override generic preferences.
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7## Inspect
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9Read the smallest complete set of evidence:
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11- Nearest `AGENTS.md`, `CLAUDE.md`, and repository instructions.
12- Root and target `Cargo.toml`, `Cargo.lock`, `rust-toolchain*`, Cargo configuration, lint and format configuration, features, targets, and continuous-integration commands.
13- Every target file in full, its parent exports, immediate callers, traits, types, errors, feature gates, platform boundaries, focused tests, and one or two tested sibling modules.
14- The exact format, check, test, Clippy, feature, and target commands used by the crate.
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16Determine the edit mode, crate kind, toolchain and minimum Rust version, public contract, ownership, resource lifecycle, error model, concurrency and cancellation, safety boundary, and invariants. Default to a hard cut; preserve compatibility only when an explicitly confirmed published contract requires it.
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18Ask only when an unresolved fact could change public behavior, durable state, safety, or migration semantics. Otherwise make repository-grounded assumptions and continue.
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20## Design and implement
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22Resolve the change in this order:
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241. Domain invariants and invalid states.
252. Ownership, borrowing boundaries, and resource lifetimes.
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