Grow Your Substack in Communities That Actually Care
Relay Post automatically matches your newsletter with hyper-niche Reddit communities where your content will resonate — then connects you with peer writers for cross-promotional guest post swaps that grow both audiences.
No spam, ever. Unsubscribe any time.
How Relay Post Works
Three systems working together to amplify your reach.
Auto-Matched Communities
We analyze your Substack content and surface the Reddit niches where your writing will actually land — r/Homelab, r/FatFIRE, r/Streetwear, and hundreds more.
Subscriber Swaps
Get paired with peer writers in your niche for mutual cross-promotion. Both audiences grow. No cold outreach. No awkward DMs.
Guest Post Carousel
A rotating system that puts your posts in front of fresh, relevant communities every week — automatically surfacing your work to readers who want it.
Built for Substack writers
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