Case: Wunka's own products
Wunka's own products send through Couryo
Couryo is built by Wunka. Before asking anyone to trust it with their email, we moved our own products onto it. They are not customers: they belong to the same company. The numbers below come from the production database, and what went wrong is here too.
- products moved between Oct 12 and Oct 21, 2026
- 9
- emails delivered since Oct 8, 2026
- 1,737
- hard bounces (11 permanent bounces)
- 0.63%
- spam complaints
- 0
Who moved
Nine products moved their email to Couryo between October 12 and October 21, 2026. In each one, the first send went out on the same day the domain was verified.
- SunoBoard
- Renderster
- Mentezinha
- Linkezera
- ViralRecast
- Start Atende
- Work Hard Everywhere
- TudoVagas
- Couryo's own contact list
Emails per product
Recipients per product, since October 8, 2026.
- SunoBoard587 recipients
- Renderster509 recipients
- Mentezinha309 recipients
- Linkezera213 recipients
- ViralRecast93 recipients
- Start Atende29 recipients
How the list stays clean
- 171 entries on the suppression lists. An address that bounced, complained or asked to leave is not mailed again.
- Since October 24, a hard bounce or a complaint in one product removes the address from marketing in all the others.
What went wrong and how we fixed it
Not everything worked the first time. Each problem became a product rule that now applies to every account.
Oct 18, 2026
Linkezera's list pushed bounces up
Confirmation reminders went to Linkezera sign-ups with wrong or fake addresses, and bounces went up. All the products were in one account, so the automatic pause limited sending for all of them, including products that had nothing to do with the problem.
Oct 18, 2026
Per-project pause
The same day, the rule changed: when one project crosses the limit, only that project steps down. Its marketing stops, its transactional email keeps going with a lower limit and the other products keep sending. The whole account steps down only as a last resort.
Oct 24, 2026
Shared suppression and a marketing brake
A hard bounce or a complaint in one product now removes the address from marketing in all the others. And when a project's 7-day bounce rate goes above 2%, its marketing slows down until the rate is back under 1.5%.
Oct 24, 2026
Checks at sign-up
The products check the address at sign-up, and the check suggests the fix for typos like gmial.com.
What is not good yet
- On October 24, Linkezera's 7-day bounce rate was 5.4%, with the list cleanup already under way.
- Mentezinha's went from 3.6% to 2.0% once the test traffic was left out of the count.
The numbers stay here as they were measured, not rounded in our favor.
What this means for you
- The per-project pause and the 2% marketing brake apply to every Couryo account.
- Every pause comes with the reason, the numbers and what to fix.