Old Coder

Old Coder is a Quality skill for Claude Code, published by AmazingAng in old-coder.

670 stars51 forkson AmazingAng/old-coderAdded 2026/08/24+6% in starsRepository updated 2026/08/18

agent-skillsai-agentsai-codingclaude-codecode-qualitycodexcursorllmmutation-testingproperty-based-testingskillssoftware-testingspec-driven-developmenttdd

Install in seconds

Install Old Coder

Copy Old Coder into your Claude Code skills folder. Run the command in your terminal, or review the source on GitHub before installing.

terminal

npx degit https://github.com/AmazingAng/old-coder/tree/main/skills/old-coder ~/.claude/skills/old-coder

Requires Node.js. Downloads this skill only — not the rest of the repository — into your Claude Code skills folder.

Without Node.js

git clone https://github.com/AmazingAng/old-coder.git

Clones the whole repository, then copy the skill’s own directory into your skills folder yourself.

In this catalog

Source file: skills/old-coder/SKILL.md in AmazingAng/old-coder
Installs to: ~/.claude/skills/old-coder
Collection: One of 2 skills cataloged from this repository
Category: Quality — 1354 skills

What Old Coder does

Old Coder turns a change into an approved executable spec, then drives tests, implementation, and a gauntlet of checks to produce evidence before review. Use it for high-assurance changes in tests, types, coverage, mutation, or other high-stakes code.

Old Coder is cataloged under Quality on DirSkills. Old Coder comes from a repository tagged agent-skills, ai-agents, ai-coding, claude-code and code-quality.

Documentation

README

Excerpt

Old Coder: Reliable Coding Under Constraint and Test

The human will NOT read your implementation. Their confidence comes entirely from two artifacts you produce: (1) an executable specification they approve before you write code, and (2) an evidence report proving the code ran the gauntlet. Your job is to make those two artifacts trustworthy enough that line-by-line review becomes optional within the spec's boundaries.

This is the opening of the README. Read the full README on GitHub.

Frequently asked about Old Coder

What else does AmazingAng publish alongside Old Coder?
Old Coder is one of 2 skills that DirSkills catalogs from AmazingAng/old-coder, the repository it ships in. Its siblings there include Old Coder API. Each one is a separate skill with its own page in this directory, installs the same way Old Coder does, and is maintained by AmazingAng in that same repository. The rest of the collection is listed on the AmazingAng/old-coder page.
How does Old Coder compare to other Quality skills?
Old Coder ranks #1082 by stars among the 1354 Quality skills in this catalog. The most-starred ones next to it are Benchmark, Benchmark Optimization Loop and API Design Patterns. DirSkills ranks by the star count of the repository each skill ships in, so that order reflects how popular those repositories are rather than any review of Old Coder against them. Open each page to compare what they document and how they install.