Ship breaking changes.Break nothing.
Releo updates every repository when an API changes, then proves nothing broke with real traffic before anything merges.
- Free during beta
- Works on the repos you already have
- Proof attached to every PR
Major version upgrade across your whole fleet
14 breaking changes · 212 endpoints · 6 teams · detected 4 minutes after release
Affected repos
38
Call sites patched
1,204
Requests replayed
0
Open divergences
0
+ 33 more repositories in this rollout
envelope: status · headers · body · timingtolerance: p95 latency ±5%policy: block on divergence
Product preview · one upstream change, five repositories, every patch proven before merge
Every company runs on APIs. Every API changes.
- API economy by 2030
- $17.3T1
- of companies are API-first
- 82%2
- a week per developer on maintenance
- 17.3h3
- typical wait to adopt a breaking change
- 34 days
Sources: 1 Kong 2024, 2 Postman 2025, 3 Stripe 2018
The release took an hour. The fallout took a month.
Day 0
With Releo, it ends on day 0. A proven pull request for every affected repository, the afternoon v2 ships.
See how it worksDay 0
Your payments API ships v2.
customerbecomescustomer_id. Amounts move to cents. Nobody owns the migration.Day 21
Someone patches it. Tests pass.
Four repositories updated, 214 tests green, merged on a Friday.
Day 34
Customers get charged 1% of the price.
The tests never called the real API. Cleanup costs $84K to $228K.
With Releo, it ends on day 0: a verified pull request for every affected repository, the afternoon v2 ships.
Tests passed. Production didn't.
// migrate billing v1 → v2 (auto-generated)const res = await client.charges.create({ amount: order.total,↳ v2 expects minor units: this charges 1/100th
currency: 'usd', customer: user.id,↳ renamed to customer_id; silently ignored
})if (res.state === 'succeeded') {↳ enum is now 'paid', so the branch never runs
await ledger.record(res.amount)}// migrate billing v1 → v2 (releo #4821)const res = await client.charges.create({ amount: toMinorUnits(order.total, 'usd'), currency: 'usd', customer_id: user.id,})if (res.state === 'paid') { await ledger.record(fromMinorUnits(res.amount, 'usd'))}From changelog to proven pull request. Without a sprint.
What do breaking changes cost you? Find out in 10 seconds.
What breaking changes cost you
Move the sliders. Every assumption is yours to change.
Default of 18h sits inside the 15 to 20 hour range per breaking change above. A working year is taken as 1,800 hours.
Cost your changes push onto customers each year
$4.8M
- Customer migrations
- 2,400
- Engineering hours
- 43,200
- Engineer-years
- 24.0
That's engineering your customers spend standing still. It shows up as support tickets, delayed upgrades and churn.
Built for both sides of every API.
Ship v2 without a ticket wave.
Customers stall on old versions you still have to run.
Faster adoption. Fewer tickets.
With Releo
- ✓A proven upgrade PR for every customer, on release day
- ✓Old versions retired on schedule
Build it with us. Ship your hardest migration first.
01
Free during beta
No invoice until launch.
02
Direct line to founders
Real answers, same day.
03
Your APIs first
We build for what you depend on.
04
Founding-partner pricing
A lower rate, kept after launch.
What we ask in return
- One API you dread upgrading
- A short call every two weeks
- Honest feedback
Limited seats. Or just email [email protected]
Pay for proof, not for seats.
Developer
Free
during beta
For one engineer and one service.
- 1 upstream API
- Up to 3 repositories
- Migration PRs
Team
Usage-based
per verified migration
For teams that depend on many APIs.
- Unlimited repositories
- Replay proof on every PR
- Blocks unsafe merges
Enterprise
Custom
annual
For API providers and regulated teams.
- PRs for your customers
- Self-hosted replay
- SSO and SLA
Questions, answered.
Something else? [email protected]
Assistants write the patch. Releo also proves it works, by replaying real traffic against old and new code. Any difference blocks the merge.
Writing on API change.
Inside a behavioral diff: what to compare and what to ignore
A behavioral diff is only useful if it ignores noise and catches real changes. How to normalize IDs, timestamps, ordering, headers, latency and secrets.
Read →Blog · 7 October 2026Deterministic verification vs LLM-as-judge for code changes
A model grading its own patch is not evidence. Why code changes need deterministic, reproducible verification, and where LLMs still earn their place.
Read →Guide · 7 min readWhat is an API breaking change?
Twelve common examples, why tests miss them, and how to detect and verify breaking changes before they reach your customers.
Read →Your next breaking change is already on someone's roadmap.
Be ready. Join the waitlist for early access.
Free during beta · Questions? [email protected]