Email infrastructure built for developers who ship.
Mailflow is a high-throughput transmission engine for product and marketing email: dynamic templates, real-time webhook tracing, and deliverability infrastructure that stays out of your way.
await fetch("https://api.mailflow.dev/v1/send", {
method: "POST",
headers: { "Authorization": "Bearer mf_live_••••" },
body: JSON.stringify({
to: "jordan@acme.co",
template: "welcome_v3",
variables: {
first_name: "Jordan",
plan: "Growth",
trial_ends: "2026-08-01"
}
})
});
// → 202 Accepted
// { "id": "msg_9f2a", "status": "queued" }Infrastructure
Everything the send path needs, nothing it does not.
Three engineering primitives underpin every message Mailflow sends.
High-deliverability infrastructure
Every send routes through warm, pre-qualified IP pools with continuous reputation monitoring, so your messages land in the inbox instead of triggering a cold-IP penalty.
< 800ms
median dispatch latency
Dynamic metadata injection
Pass a flat variables object at send time and Mailflow maps every key straight into your raw template array, no manual string interpolation, no template-engine lock-in.
1 request
template + data, merged server-side
Real-time webhook tracing
Every delivery state change, sent, delivered, opened, clicked, streams to your endpoint the instant it happens, so your product can react to engagement without polling.