Sharding
“Horizontal sharding for your personality. Work-you on shard 1, drunk-you on shard 4, in-therapy-you on shard 7. Cross-shard queries require a JOIN no one can afford. Split-brain incident when your boss runs into your college roommate at a wedding.”
The Problem
“You” is currently a single-instance monolith. One database, one personality, one tone of voice. At low QPS this is fine. But your mother-in-law just joined LinkedIn, your therapist follows your finsta, and a guy from college named Devin replied-all to a work calendar invite. P99 latency on “who am I right now” is 11 seconds. The instance OOMs at family dinners.
The Solution
Horizontally shard yourself. Each shard owns a tonally-consistent slice of who you are, with its own connection pool. Reads are routed by shard_key = SHA1(audience). No more cross-pollination, no more accidentally telling HR about the cabin trip.
Cross-Shard JOIN
Sometimes a query lands that spans two shards — e.g. your boss messages the group chat by mistake. The router has to fan out, drain buffers, and reconcile state. Latency is measured in therapist sessions, not milliseconds.
Split-Brain Incident · SEV-1
A wedding. Two shards meet in physical space. Without a coordinator, both believe they are the canonical you. Pronouns desync. Stories diverge in real time. The replication lag is 4 years.
- 18:42· your boss (
shard 0) sits next to your college roommate (shard 6) at table 7. - 18:44· roommate opens with “remember the thing in Cabo”. Network partition begins.
- 18:47· your laugh latency degrades. You attempt a hot patch (“ha… well that’s a long…”).
- 18:51·split brain: both shards claim authority. Pronouns desync. You begin referring to yourself in the third person.
- 19:03· you initiate an emergency failover to
shard 7(therapy-you) and excuse yourself to the bathroom. Quorum restored.
Pricing
TAM
The Ask
$7M seed. Builds the router, the consistent hash ring, and a fleet of eight earpieces that whisper which shard is currently primary. Hiring: two distributed systems engineers and one improv coach to write the tonal embeddings.
Series A pitch:“We’re Vitess for the self. The monolith was never going to scale.”