Spec-driven development (SDD) for teams
Write the spec before the agent writes the code, and build the whole team around it. Feature1 is the product operating system where PMs and developers write, agree and track specs together, and your coding agent builds from them.
What is spec-driven development?
Spec-driven development (SDD), also called spec-first development, is a way of building software with AI coding agents in which a written specification comes first. You describe what a change must do and how you will know it is done, the agent builds to that spec, and a person verifies the result against it. The spec, not the prompt, is the source of truth.
Specify
The feature, its user stories and acceptance criteria.
Plan
How it will be built, split into tasks.
Build
The coding agent implements the tasks.
Verify
A person checks the result against the criteria.
Spec-driven development tools, and where they stop
GitHub Spec Kit, Kiro and OpenSpec made SDD practical. They keep the spec as markdown in the repository, next to the code, which works well for one developer and one agent. When a team joins in, it gets harder:
- The PM needs a branch and a pull request to change one sentence.
- Two people edit the same spec and hit a merge conflict on plain English.
- The discussion about why lives in pull request comments and disappears on merge.
- The file cannot hold the customer signals behind the spec, its approved revisions, progress, or whether the feature is used after release.
The spec is a product decision. Feature1 is a spec-driven development tool for the whole team: it keeps the spec where everyone can work on it, with everything around it attached, and serves it to your AI coding agent over MCP.
New to SDD? Adopt spec-driven development with your team
Book a proof of concept (POC). We set SDD up with your PM and one developer and stay with you, hands on, until two real features are delivered.
- Week 1. NDA, read-only GitHub access, then the product strategy and roadmap with your PM in Feature1. The first two features are specified with acceptance criteria.
- Week 2. Your developer builds both features with their own coding agent, reading the criteria over MCP. We review against the criteria together and ship.
Proof of concept (POC)
$500 paid only when the two features ship
- One to two weeks, your PM and one developer
- Your developer writes the code; we guide the process
- You keep the strategy, roadmap and specs
Already doing SDD? Keep your tools and bring the whole team in
Your developers keep Spec Kit or their own workflow. Feature1 becomes the place the rest of the team works on the spec.
- Write and comment on specs without touching Git, and approve each revision.
- Link every spec to the initiative and customer signals behind it.
- See progress story by story, then adoption and errors after release.
- Your agent reads the approved criteria over MCP, and Feature1 exports Spec Kit files for your developer to commit.
7-day free trial
Free no credit card
Sign up, invite your team and move your next spec into Feature1. Connect your coding agent when you are ready.
Start the free trialTeams already working this way
- SatoriXR. Delivery got faster and deciding became the constraint. They hired a second product manager, not a third developer.
- Quantem. A junior developer built an MCP layer in one day from written acceptance criteria. The context took four to five days; the build took one.
- Jarshare. A Replit store with one unintegrated server file became a real product once its next features were specified against what it already did.
Spec-driven development: questions people ask
What is spec-driven development?
Spec-driven development (SDD) is a way of building software with AI coding agents in which a written specification comes first. You describe what a change must do and how you will know it is done, the agent builds to that spec, and a person verifies the result against it.
How is spec-driven development different from test-driven development?
Test-driven development writes a failing test before the code. Spec-driven development writes the intent first: the feature, its user stories and acceptance criteria, in language the whole team can read. Good acceptance criteria often become the tests, so the two work well together.
What are the main spec-driven development tools?
GitHub Spec Kit, Kiro and OpenSpec are widely used. They keep specs as files in the repository and drive the coding agent from them. Feature1 works alongside them as the place the whole team writes, agrees and tracks the spec.
How do we adopt spec-driven development in a team?
Start with one or two real features, not a process rollout. Write the acceptance criteria before any code, let the developer build with their agent from them, and review against the criteria. The Feature1 POC does exactly this with your PM and one developer in one to two weeks.
Why not keep specs only in the repository?
For one developer, a markdown spec in the repository is fine. For a team it means the PM works in Git, edits collide as merge conflicts, the discussion is lost in pull request comments, and the file cannot carry the customer signals, approved revisions, progress or usage that surround the spec. Feature1 keeps all of that with the spec, and the agent still reads it while it builds.
Do we have to replace Spec Kit?
No. Your agent reads the approved criteria from Feature1 over MCP, and Feature1 exports Spec Kit files for your developer to commit. Keep the repository workflow you have.
What is in the POC?
One to two weeks with your PM and one developer. We set up spec-driven development with your team and stay with you until two features are delivered from acceptance criteria held in Feature1. An NDA is signed before anything is read, GitHub access is read-only, and you pay the $500 only when the two features ship.
Is there a free trial?
Yes. Feature1 has a 7-day free trial with no credit card. Invite your team, write your next specs together and connect your coding agent.