@fetchsandbox

Testing Resend is not just POST /emails

10h ago · 3 min read · I was trying to integrate Resend like an end user would. The first call was straightforward. POST /emails You send the payload, get a 200, and now you have an email id. That part is not where most of

Test Cal.com booking flows without calendar chaos

May 12 · 4 min read · Scheduling integrations do not usually break on the first request. They break after the booking exists. The user gets an email. The host has Google Calendar connected. Your app sends its own ICS file.

Polar external_id reconciliation: the customer field that keeps checkout tied to your user

May 7 · 4 min read · Checkout is not where a billing integration starts. For a SaaS app, it usually starts one step earlier: Can this billing customer be tied back to the right user in my app? That tiny mapping is easy to

Why Paddle's subscription.activated arrives before subscription.created

May 1 · 3 min read · You'd think events fire in the order things happen. They don't. I was building a Paddle integration last week. Subscription billing, nothing fancy. Customer clicks buy, Paddle handles checkout, my app

Test Paddle webhooks without account verification

Apr 30 · 3 min read · You can't test a Paddle subscription cancel webhook until Paddle has verified your business. That takes days. Paddle's billing API handles subscriptions, payments, and the entire checkout flow. The AP