DeliverabilityComing soon
DKIM, SPF, DMARC — what they actually do
A grounded look at the three DNS records every sender learns about the hard way, and why send0 verifies, watches, and alerts on all three by default.
8 min readRead
Blog · send0
Notes on email, done right.
Product updates, engineering posts, and grounded takes on deliverability — written by the team building your inbox and running the pager.
Featured
CompanyComing soon
Why we're building send0
We rebuilt sending and receiving onto one SDK because the status quo was a sending API bolted to a separate inbound parser. Here's the short version of the thesis.
5 min readComing soon
Latest posts
5 drafts in the queueEngineeringComing soon
Programmable inboxes: parsing inbound email
How we turn raw, messy MIME into clean JSON on the email.received webhook — and why an inbound route is all the setup it takes.
7 min readRead
EngineeringComing soon
Idempotency keys done right
Retries are unavoidable. Duplicate emails are not. A walk through how send0 makes POST /v1/emails safe to retry and easy to reason about.
6 min readRead
DeliverabilityComing soon
Automated IP warmup, explained
What a warmup schedule actually does to your sender reputation, when to graduate from the shared pool to a dedicated IP, and how send0 automates it.
9 min readRead
EngineeringComing soon
Why we ship test-mode keys first
sk_test_ keys aren't a checkbox — they shape how your team writes code. Here's what a proper test environment buys you.
4 min readRead
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