Substack
Hosted newsletter platform with social network features.
Substack is closed and opinionated: 10% revenue cut, no API, no custom domains for free, but distribution and recommendations are real. Largely outside the developer toolchain conversation.
The question here is which one a backend engineer would rather operate. That means SDK depth in the language already in use, whether a retry can safely be replayed, how much the event log tells you when a customer says the email never arrived, and whether the pricing curve stays sane as volume grows.
Against password resets, receipts, and magic links shipped from application code, Substack covers developer experience, and does not cover SDK breadth, idempotency keys, operating track record, event stream, and webhook coverage. Whether that gap matters depends on how central those are to the build.
- DX score: 2/10
- SDKs: None
- Idempotency keys: No
- Operating since: 2017
- Event stream: No
- Best published rate per 1,000: Tiers not published in comparable form
- Webhooks: No
- Deliverability: Reasonable for content-driven newsletters.
- Free tier: Free, 10% of paid subscriptions
Reasonable for content-driven newsletters.
Writers who prioritize distribution over flexibility.
- › Distribution via the Substack network
- › No platform fees beyond revenue cut
- › No API, no automation, no custom domain on free
- › Lock-in to platform
Features at a glance
| API | No |
| SMTP | No |
| SDKs | None |
| Webhooks | No |
| Templates | basic |
| React Email | No |
| Batch send | Yes |
| Scheduled send | Yes |
| Suppressions | Yes |
| Multi-tenant | No |
| Inbound parsing | No |
| Event stream | No |
| Idempotency keys | No |
| Dedicated IP | No |