# Software Implementation

Write the minimal production code needed to make failing TDD tests pass (Green phase of...

- Repository: https://github.com/stencila/stencila (914 stars)
- Category: Testing
- License: Apache-2.0
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add stencila/stencila --skill software-implementation -g -a claude-code -y`
Codex: `npx skills add stencila/stencila --skill software-implementation -g -a codex -y`
Cursor: `npx skills add stencila/stencila --skill software-implementation -g -a cursor -y`
Gemini CLI: `npx skills add stencila/stencila --skill software-implementation -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add stencila/stencila`

## Description

Write the minimal production code needed to make failing TDD tests pass (Green phase of red-green-refactor). Use when failing tests exist and production code must be written or modified to satisfy them. Reads and interprets failing test output, discovers codebase conventions (module layout, naming, import patterns, error handling, coding style), writes focused production code that satisfies test expectations without over-engineering, integrates new code with existing modules, types, and APIs, handles revision feedback from failed test runs, and verifies implementation compiles or parses before handing off to test execution. Works with any language or framework.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

## Overview

Write the minimal production code needed to make failing TDD tests pass. This skill handles the "green" phase of a red-green-refactor cycle: given failing test output, test file paths, and slice context, it discovers the codebase's conventions, writes or modifies production code so the tests pass, and verifies the code compiles or parses cleanly.

The core principles are:

- **Discover first, prescribe only as fallback.** Adapt to whatever language, framework, and conventions the codebase already uses.
- **Minimal and sufficient.** Write exactly the code needed to make the failing tests pass, no more, no less. Do not add features, optimizations, or abstractions beyond what the tests require.
- **Tests are the specification.** The failing test output defines what the code must do. Do not second-guess the tests or add untested behavior.

The implementation must:

- Make all specified failing tests pass
- Follow the codebase's existing conventions (naming, module layout, error handling, coding style)
- Compile or parse without errors or warnings where possible
- Integrate cleanly with existing modules, types, and APIs
- Not break any existing tests

## Required Inputs

This skill requires the following information to operate:

The rest: https://github.com/stencila/stencila/blob/HEAD/.stencila/skills/software-implementation/SKILL.md