Background sending with per-sender rate limits #36

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opened 2026-10-15 01:18:54 -04:00 by vmanne-poc · 0 comments

vmanne-poc commented

2026-10-15 01:18:54 -04:00

Owner

Today:

"Send now" sends every email inside the HTTP request, one after another, creating a new SMTP connection each time.
Large lists time out the request.
There is no way to respect a provider's limits. The SES sandbox allows 1 email per second, and production SES has a per-account rate.

Plan

Sending moves to a background job:
- POST .../send claims the campaign (it is already atomic) and returns right away
- a worker (the scheduler process) sends in batches
- the campaign shows progress (sent / total)
Use a DB-backed queue, with no new infrastructure: Message rows with queuedAt and no sentAt or failedAt are the queue. The worker restarts safely after a crash, and nothing is sent twice. Each row is claimed before sending.
Per-sender rate limits: emails per second, per minute and per hour, all optional, set on the sender form.
Reuse one pooled transport per sender per batch.
Retry temporary failures (4xx SMTP replies) with back-off. Permanent failures (5xx) set failedAt and keep the error text, which shows in the report.
The UI shows SENDING with progress and refreshes automatically.

**Today:** - "Send now" sends every email inside the HTTP request, one after another, creating a new SMTP connection each time. - Large lists time out the request. - There is no way to respect a provider's limits. The SES sandbox allows 1 email per second, and production SES has a per-account rate. **Plan** - Sending moves to a background job: - `POST .../send` claims the campaign (it is already atomic) and returns right away - a worker (the scheduler process) sends in batches - the campaign shows progress (sent / total) - Use a DB-backed queue, with no new infrastructure: `Message` rows with `queuedAt` and no `sentAt` or `failedAt` are the queue. The worker restarts safely after a crash, and nothing is sent twice. Each row is claimed before sending. - Per-sender rate limits: emails per second, per minute and per hour, all optional, set on the sender form. - Reuse one pooled transport per sender per batch. - Retry temporary failures (4xx SMTP replies) with back-off. Permanent failures (5xx) set `failedAt` and keep the error text, which shows in the report. - The UI shows SENDING with progress and refreshes automatically.

vmanne-poc added this to the Phase 10: Contacts, senders & sending milestone

2026-10-15 01:18:54 -04:00

vmanne-poc added the

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2026-10-15 01:18:54 -04:00

vmanne-poc referenced this issue from a commit

2026-10-15 08:41:32 -04:00

Send campaigns in the background with rate limits and retries

vmanne-poc referenced this issue from a pull request that will close it,

2026-10-15 08:51:37 -04:00

Phase 10: contacts, senders, background sending, segments, rate limits #52