#Testing

Overnight Test Generation Pipeline

From zero tests to full coverage in one night.

The Scenario

You have a growing codebase with inconsistent test coverage. Some modules have thorough tests, others have none. Writing tests manually would take weeks. You need a way to generate comprehensive test suites without blocking feature development.

Who Is This For

Solo developers and small teams who need test coverage but can't afford to dedicate sprint time to writing tests. Especially useful after a rapid prototyping phase when you're ready to harden your codebase.

Pipeline Steps

01

Scan for Untested Modules

Claude Code

Agent analyzes your src/ directory, identifies modules without corresponding test files, and generates a task list ranked by importance.

02

Generate Test Files

Claude Code

For each untested module, the agent generates a comprehensive test file with unit tests, edge cases, and integration scenarios.

03

Run Test Suite

Jest / Vitest

Zowl executes the full test suite. Passing tests are kept; failing tests get fed back to the agent with error context.

04

Fix Failing Tests

Claude Code

Agent receives failing test output and rewrites tests to fix assertion errors, missing mocks, or incorrect assumptions.

05

Coverage Report + PR

Git

Zowl generates a coverage report, commits all passing tests, and opens a PR with the coverage diff.

Expected Results

  • Test coverage increase from baseline to 80%+ in one overnight run
  • Individual test files for each untested module
  • Coverage report showing before/after metrics
  • Clean PR ready for review with all tests passing
Estimated Runtime6-10 hours overnight for a medium codebase (50-200 modules)

Frequently Asked Questions

Depends on codebase size and API rate limits. A typical overnight run generates tests for 30-80 modules with 3-10 test cases each.

Configure your pipeline prompt to emphasize edge cases, error handling, and integration scenarios. You can also add a review step where a second agent evaluates test quality.

Absolutely. Schedule the pipeline to run every Sunday night and keep coverage from degrading as new code lands.

Try Zowl for This Workflow

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