Comparison
Bystep vs OpenSpec
A free, open-source spec-driven framework: project.md plus change proposals with spec deltas, read and written by your own agent via CLI conventions.
What OpenSpec is
A free, open-source spec-driven framework: project.md plus change proposals with spec deltas, read and written by your own agent via CLI conventions.
- Pricing
- Free, open source. No hosted service.
Feature matrix
Where the two actually differ
Every Bystep item here is live in the product today — not a roadmap promise. Competitor claims we couldn't verify first-hand are marked “as far as we know.”
| Bystep | OpenSpec | |
|---|---|---|
| PRD generation | Yes | Partialproject.md + change proposals are structured like a spec, written through your own agent, not a wizard |
| Acceptance criteria per task | Yesids like AC-checkout-1, derived from the PRD, editable by hand | PartialChange proposals define spec deltas/scenarios; as far as we know there’s no executable check attached |
| Verification gate | Yes`task complete` returns 409 without passing evidence or a recorded override | No |
| Evidence panel | Yestest output, diff stat, files touched, optional screenshot — stored, not just claimed | No |
| Works with any coding agent | YesClaude Code, Cursor, Codex, Copilot, OpenCode, Gemini CLI via CLI + MCP | YesSame category as Spec Kit — plain files any agent can read/write |
| Import / export formats | YesSpec Kit, OpenSpec, Backlog.md, Task Master, Kiro, Claude Code Tasks, GitHub Issues, Linear | PartialOne of the formats Bystep imports/exports; OpenSpec itself does not read other tools’ formats as far as we know |
| Client mode / proposal | Yesclient-viewer share page + proposal for the Studio tier | No |
| Cost per feature | Yesper feature, not just per session | No |
| Indonesian language & payments | Yesen/id UI, IDR pricing, QRIS/VA | No |
| Open-source CLI | Yes`@bystep/cli` + `@bystep/mcp`, MIT | Yes |
Honest answer
When to choose OpenSpec instead
- You want a lighter-weight, change-proposal-centric alternative to Spec Kit and don’t need a hosted UI.
- Your workflow is already git-native and markdown-first — you just want your agent to follow a convention, not a service.
- You don’t need acceptance criteria enforced, evidence stored, or a client page — just a readable history of what changed and why.
Bring what you've got, add the gate
Import your existing spec or backlog, let Bystep add acceptance criteria and a verification gate, and keep working with the agent you already use.