Building in Public — how we build Rythm, in the open.
Architecture decisions, engineering tradeoffs, and the non-custodial design behind Rythm.
What Happens When You Cancel Rythm?
Rythm has no lock-in by design. Cancel anytime and your inbox returns to exactly what it was before. Here is the honest unwind.
What Happens When Rythm Goes Down? The Fail-Open Promise
Every SaaS goes down occasionally. Rythm's architecture guarantees your email still delivers even when we have a problem. Here is how.
What Rythm Doesn't Do (And Why That's the Point)
Most software tries to do more. Rythm tries to do less. The things we deliberately left out say more about the product than the things we put in.
The Cash App Path: How Senders Pay Without 'Having Bitcoin'
The most common adoption objection is 'my contacts aren't Bitcoin people.' Here is the truth about how senders actually pay the cover charge in 2026.
What Your Senders Actually See: The Default Rythm Verification Email
The #1 fear before turning on an email paywall: 'will my contacts think I'm rude?' Here is the actual default message Rythm sends.
What Happens to a Filtered Email That Was Actually Important?
The loss-aversion question every new Rythm user asks. Here's the honest answer: nothing is deleted, everything is rescuable, and the system is fail-open.
How It Actually Works Under the Hood
How does a web app process payments between strangers without holding anyone's money? Here's the exact flow, from Lightning invoice to token redemption.
How Rythm's Non-Custodial Architecture Works
A technical deep dive into how Rythm verifies payments without holding funds, storing proofs, or reading email content. Cashu ecash + Lightning.
Why We Chose Deterministic Over Probabilistic Email Filtering
Every email filter uses AI to guess. We built one that doesn't guess at all. Here's the technical rationale behind Rythm's binary approach.