Which size is my change?
- You will learn: how GTM sizes a change, and what each size asks of you.
- Reading time: 4 minutes.
- Before this: Your first Feature helps, but is not required.
Three questions decide it. GTM sorts every change into one of three tracks: a Fix (at most 3 files), a Feature (one capability on one branch) or a Milestone (several branches). You describe the change; GTM asks at most two questions and proposes the track.
How to read it: start at the amber step, answer each question from the top, and stop at the first track you reach.
What does each track ask of me?
A few terms first:
- Checkpoint: a moment where you decide; the rest runs without you.
- Mockups: one page showing each new screen in light and dark.
- Spec: the document that says what will be built and how each part is checked; you approve its ten-line summary.
- Final review: one check of the whole branch against the spec, once every task is done, before you give the go.
What does a Fix ask of me?
Two checkpoints. A Fix changes at most 3 files. It has no mockups, no spec and no final review.
How to read it: two amber steps, the design and the go. Everything else is the team’s.
What does a Feature ask of me?
Three checkpoints. A Feature is one capability on one branch.
How to read it: three amber steps; with no screen changes, the first one is skipped.
A small Feature changes no screen, schema, migration or sign-in, and touches at most twice the 3 files a Fix may change, so 6 files by default. The architect writes its spec and plan in one pass. You still approve the summary and give the go; the plan is written again only if you answer a decision otherwise or the spec changes.
What does a Milestone ask of me?
One split, then Features. A Milestone spans several branches, or opens a new surface.
How to read it: you approve the split once, then each branch has a Feature’s three checkpoints.
The same answer as a table, with agent times measured on GTM’s own changes:
| Track | You decide | Agent time |
|---|---|---|
| Fix | the 3-line design, then the go | about a minute (71 s measured) |
| Feature | the mockups if screens change, the summary, the go | 11 to 58 min measured |
| Milestone | the split into branches, then each branch as a Feature | hours |
What if a Fix grows?
Every Fix has a file limit, 3 files by default.
How to read it: a Fix that passes its limit continues from the spec, so you gain one amber step. A change never goes back down a size.
A Fix that touches security or data code stays a Fix. The security or data reviewer checks it, as on any task.