skills

Use Atlas to initialize Nim projects, install or update Atlas-managed dependencies, configure dependency directories, inspect Atlas-generated nim.cfg paths, handle Atlas overrides, features, plugins, lockfiles, and local Nim environments. Use when setting up or repairing Nim dependency workflows that use Atlas instead of Nimble's global package path.

Design clear public Nim APIs for libraries and modules, including exported types, constructors, parameter ownership, lookup functions, error contracts, and container-style interfaces. Use when creating or reviewing a Nim library API, designing an exported module surface, or deciding how callers should construct, pass, access, and validate data.

Bind C libraries to Nim and make them build reliably across Linux, macOS, and Windows, including headers, types, linking, shared-library loading, and CI/release workflows. Use when wrapping a C dependency, fixing Nim FFI build issues, or setting up cross-platform GitHub Actions for a Nim native library project.

Turn low-level C FFI bindings into an idiomatic Nim API, with safer types, cleaner module boundaries, resource management, callbacks, enums, bitflags, and exception-based error handling. Use when building a high-level Nim wrapper around a C library or improving the usability of existing raw bindings.

Organize Nim modules and multi-step workflows with explicit state ownership, cohesive boundaries, narrow exports, and structured orchestration. Use when refactoring a large Nim file, splitting logic across modules, designing parser-style stateful code, or simplifying nested helpers and hidden mutable state.

Debug Nim compile failures, crashes, wrong results, macro expansion, ownership behavior, and unsafe-memory defects using focused reproduction, stack traces, inspection, compiler expansion, and sanitizers. Use when diagnosing runtime failures, release-only behavior, generic or macro issues, unexpected copies, pointer bugs, or memory leaks.

Find reliability and security defects in Nim code. Use when reviewing Nim source for bugs, auditing parsers or protocol handlers for crashes, checking FFI or ownership code for memory safety, or reducing false positives in code review findings.

Document exported Nim modules and APIs with doc comments that `nim doc` actually picks up, including module docs, proc and type docs, field docs, and runnable examples. Use when writing documentation for a Nim library or fixing docs that are missing, attached to the wrong symbol, or rendering incorrectly.

Design clear Nim error-handling flows; when to raise exceptions vs return `Option`/`bool`, how to enforce non-raising contracts, and where to translate or record failures. Use when reviewing failure behavior, exception boundaries, recovery, or batch processing that needs per-item error reporting.

Set up and run libFuzzer-based fuzz targets for Nim code, including harness wiring, compilation flags, corpus management, structure-aware mutators, and crash triage. Use when adding fuzzing to a Nim project, building a fuzz harness for a parser/protocol/format handler, or reproducing and minimizing a fuzzer-found crash.

Implement and review Nim ARC/ORC ownership hooks for types that manually manage resources, including move-only, deep-copy, refcounted, and copy-on-write patterns. Use when a Nim type owns pointers, buffers, file descriptors, or custom heap memory and you need correct `=destroy`, `=copy`, `=dup`, `=sink`, or move semantics.

Write clear, consistent Nim code in a simple stdlib-aligned style, covering imports, naming, proc vs func vs template choices, local variables, constructors, formatting, and control flow. Use when writing new Nim code or reviewing a Nim module for readability, consistency, and low-noise style decisions.

Write and run deterministic Nim tests, including isolated test files, expected-exception checks, multi-configuration builds, and sanitizer integration. Use when setting up a Nim test suite, testing failure behavior, running tests across debug/release/danger modes, or adding AddressSanitizer support.

Build and debug Nimony compile-time plugins for code generation and DSL rewrites. Use when replacing Nim macros with Nimony plugins, writing or reviewing template, for-loop, module, type, or import plugins, or diagnosing NIF traversal and generated output.