Email and Backend

DNS (Domain Name System)

domain settings.

SPF / DKIM / DMARC

allow senders, sign messages, set failure policy + reports… Sender Policy Framework, DomainKeys Identified Mail, Domain-based Message Authentication

Return-Path

where bounces go.

BIMI

show your logo in inboxes (optional)… Brand Indicators for Message Identification

Warm-up

start with low volume to build reputation.

Bounce / complaint

failed delivery / spam report.

Serverless/edge functions

small on-demand code close to users.

Job/worker/queue

background tasks (e.g., weekly matching).

Cache/CDN

faster delivery via stored copies.

Cache-Control/ETag

how long responses can be cached.

Env: dev/staging/prod

local / pre-prod / live.

Secrets management

keep keys in env vars/secret store.

Concurrency/race condition

simultaneous actions clash; use locks/transactions.

Timeout/retry/backoff

fail safely and retry with delays.