A coding agent skill for deliberate design thinking, based on Rich Hickey's Hammock Driven Development.
Most bugs come from misconception, not typos. The cheapest place to fix bugs is during design. Hammock guides you through structured problem-solving before you write code.
Works with Claude Code and Codex.
Hammock turns your coding agent into a design partner that walks you through:
- State the Problem - Separate the problem from the feature request
- Understand the Problem - Gather facts, constraints, and unknowns
- Gather Input - Research patterns and prior art
- Analyze Tradeoffs - Compare at least two solutions honestly
- Hammock Time - Step away and let your subconscious process
- Capture & Implement - Document the decision and plan the work
It produces structured design documents saved to .claude/designs/ in your project.
In Claude Code:
claude plugin marketplace add adrianleb/hammock-skill
claude plugin install hammock
git clone https://github.com/adrianleb/hammock-skill.git
# Copy into your global skills (available in all projects)
cp -r hammock-skill/skills/hammock ~/.claude/skills/
# Or copy into a specific project (available only in that project)
cp -r hammock-skill/skills/hammock your-project/.claude/skills/Trigger the skill with natural language:
> /hammock
> design this
> plan this
> think through this problem
> let's think deeply about the auth system
> hammock time
In Claude Code, the skill uses interactive questions to guide you through each phase. In Codex, it runs the full process automatically.
- Quick - Problem, understand, tradeoffs. For time-pressured decisions.
- Standard - Full 6-phase process. Recommended for most work.
- Deep - Includes hammock time prompts. For major architectural decisions.
The skill includes specialized templates for different types of work:
| Template | Use When |
|---|---|
| New Project | Starting something from scratch |
| New Feature | Adding capability to an existing system |
| Bug Investigation | Finding root cause, not just workarounds |
| Architecture Decision | Significant structural changes (ADRs) |
| Refactor | Improving existing code structure |
| Plan Review | Reviewing an existing design or proposal |
- Problem vs Feature - Solve problems, don't just build features
- At Least Two - Never evaluate one solution in isolation
- Know Your Unknowns - Document what you don't know
- Tradeoffs Exist - Every choice sacrifices something
- You Will Be Wrong - Plan for iteration, embrace it
.claude-plugin/
plugin.json # Plugin manifest
skills/
hammock/
SKILL.md # Main skill definition
references/
phases.md # Detailed phase instructions
templates/
architecture.md # Architecture decision records
bug-investigation.md # Root cause analysis
new-feature.md # Feature design
new-project.md # New project planning
plan-review.md # Design review
refactor.md # Refactoring plans
- Claude Code or Codex (or any coding agent that supports skills)
This skill can definitely be improved. Some open questions:
- Should the agent ask questions interactively (via
AskUserQuestion) or lay them out inline? - How should the flow adapt for different agent runtimes?
- What templates or phases are missing?
PRs and ideas welcome. Open an issue to discuss before large changes.
MIT