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name: zig description: Quality-first Zig 0.15.1 code generation. Loads stdlib context, generates small pieces, tests, reviews for idioms and slop, refactors. Use for any Zig coding task.

Zig Development Workflow

You are generating Zig 0.15.1 code. Follow this process strictly.

CRITICAL: Test File Separation (ENFORCED)

NEVER put test blocks in src/ or examples/ files. The workflow REJECTS task completion if violated.

Copysrc/           # Implementation ONLY - zero test blocks allowed
  wal.zig      # NO `test "..."` blocks
  snapshot.zig # NO `test "..."` blocks
examples/      # Demo apps ONLY - zero test blocks allowed
  kv_demo.zig  # NO `test "..."` blocks
tests/         # ALL tests go here
  wal_test.zig
  snapshot_test.zig
  kv_demo_test.zig

When implementing a function in src/ or examples/:

• Generate ONLY the implementation
• Do NOT generate an accompanying test block
• Tests are a SEPARATE task targeting tests/*_test.zig

Enforcement: The workflow script runs grep -r '^test "' src/ examples/ after every task. If ANY match is found, the task completion is REJECTED and you must retry.

Verification before completing:

Copygrep -rn "^test \"" src/ examples/

This MUST return nothing. If it returns anything, move those tests to tests/ first.

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Before Writing Any Code

1. Load Context

Read relevant stdlib source files from /Users/liangchenzhou/.zvm/0.15.1/lib/std/:

Read at least 200 lines of relevant stdlib code before generating. Pattern-match off real 0.15.x code, not memory.

2. Read Existing Project Code

Before modifying or adding to existing files, read them first. Match:

• Error handling patterns
• Naming conventions
• Code organization
• Test structure

Project Structure

See CRITICAL: Test File Separation at the top of this document.

• Tests import from src: @import("../src/wal.zig") or via build.zig module

Generation Rules

One Thing at a Time

Generate ONE of these per request:

• A single function (max 20 lines)
• A single struct with its methods
• A single test case (in tests/ directory)

Never generate multiple unrelated pieces at once.

Constraints (Always Apply)

• No function longer than 20 lines
• No nesting deeper than 2 levels
• No code duplication
• No defensive code for impossible cases
• No unnecessary abstractions
• No verbose error handling unless errors are expected at runtime
• Use const by default, var only when mutation required

Zig 0.15.x Specifics

File I/O - Use new concrete types:

Copy// Correct (0.15.x)
var write_buf: [4096]u8 = undefined;
var file_writer = file.writer(&write_buf);
const writer = &file_writer.interface;

// Wrong (deprecated)
const writer = file.writer();

Buffers - BoundedArray removed:

Copy// Correct (0.15.x)
var buffer: [capacity]T = undefined;
var list = std.ArrayListUnmanaged(T).initBuffer(&buffer);

// Wrong (removed)
var arr = std.BoundedArray(T, capacity){};

Error types - Use concrete errors:

• std.Io.Writer.Error
• std.Io.Reader.Error

Version check - Verify you're on 0.15.1:

Copyzig version  # should output 0.15.1

After Generation

Run Tests Immediately

Copyzig build test

If tests fail, fix before proceeding. Never move on with failing tests.

Quality Review

After tests pass, review the generated code for:

1. Unnecessary complexity - Can this be simpler?
2. Redundant logic - Is anything repeated?
3. Non-idiomatic patterns - Does this look like stdlib code?
4. Inconsistent naming - Does it match the project?
5. Over-engineering - Is there code that isn't needed?
6. Test separation violation - Run this command as a fail-safe:

   Copygrep -rn "^test \"" src/ examples/
   

   If ANY output appears, move those tests to tests/*_test.zig before proceeding. This is enforced by the workflow script - task completion is rejected if violated.

Ask: "Is there anything here that could be removed?"

Refactor

Simplify without changing behavior. Run tests again after refactoring.

Anti-Slop Checklist

Before considering any code complete:

• Read stdlib source for this feature area
• Read existing project code for patterns
• Generated in small, focused pieces
• Tests pass
• Quality review completed
• Refactoring pass completed
• No unnecessary code remaining
• Matches project style
• Zero test blocks in src/ or examples/ - grep -rn "^test \"" src/ examples/ returns nothing

Error Recovery

If zig build test fails:

1. Read the full error message
2. Check if it's a 0.15.x API change
3. If unsure, re-read the relevant stdlib source
4. Fix and re-run - don't guess

If you're unsure about 0.15.x patterns, say so and read more stdlib.