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v0.2.1

Cupel

English specs to Go tests, via Claude

$ go install goforge.dev/cupel/projects/cupel@latest
Source repository pkg.go.dev

Cupel turns an English-language specification into Go tests by calling Claude, and writes them into a goforge component. For one spec it produces three styles of test:

The current release is v0.2.1. Cupel now has a model-agnostic backend boundary with both Anthropic API and local Claude CLI implementations, while its own semantic core is authored in Go+ and shipped as generated Go.

  1. Example tests — concrete, readable cases (plus testable Example funcs).
  2. Parameterized / data-driven tests — table-driven t.Run cases.
  3. Property-based tests — invariants checked with the standard library’s testing/quick.

The output is not a loose file. Cupel enforces the goforge architecture on it: the model reply is de-fenced, parsed, required to declare the external <iface>_test package, gofmt-formatted, written into components/<name>/ alongside a valid interface / internal/ / component.yaml scaffold, and then validated by running goforge check.

A cupel is the porous vessel an assayer uses to refine raw metal — here it refines raw prose into tests.

Cupel is itself a goforge workspace, so its own structure obeys the same worker-type discipline it enforces on its output: the pure spec/prompt/ architecture components stay pure, while the Claude-backed claude/gen components carry their input/output effects up to the cli base.

Install

go install goforge.dev/cupel/projects/cupel@latest   # the cupel CLI
go install goforge.dev/goforge@latest                 # needed for the check step