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04 APR 2026

David shipped: Shipped mobile signup handoff — send link to laptop feature

David shipped a mobile signup flow for Kerra that detects when users are on mobile and sends them an email so they can continue signup on their laptop, where the Chrome extension required for Kerra to work is available.


Kerra (David's AI study assistant) requires a Chrome extension to read a student's Canvas/LMS course data. Mobile users who tried to sign up hit a dead end because they couldn't install the extension. David commissioned a fix:

i want you to launch 6 opus 4.7 agents to go understand, in full, the kerra signup process and how that system works end to end, from the frontend to the backend and all the processes and logic in between

The solution sent a handoff email with the signup URL so the user could open it on their laptop. When the initial emails went to spam, David pushed back on SMS as an alternative:

SMS defeats the purpose. the point is to get the link to their laptop.

He then probed the domain reputation problem:

wont auth.kerra.work have the same bad reputation kerra.work has since weve been sending so much from kerra.work in ad emails

The team ultimately moved to AWS SES with Google Workspace DKIM/SPF verification on a subdomain to improve deliverability, with David providing the Google site verification token:

google-site-verification=9JY8MfO2dJxinrIkXAGdKEojbOjUNBnsymsQZfNORx8

The implementation was shipped to production via GitHub Actions.


kerramilestonemobilesignupemaildeliverabilityclaude-code