Built like a ledger. Runs like a river.

Project River Fish is a river of apps for everyone, anywhere in the world — offline-first, append-only, provably correct. The keyboard-first point of sale is the first fish in the water. More are swimming behind it.

codename: riverfish · phase 0 · brand tbd

fig. 01 — river fish, sampled at 9px

01

Stock is a sum, never a cell

Every movement of inventory or money appends an immutable row. On-hand stock is SUM(delta) — there is no mutable column to corrupt, so “−22.5 PAIR” can never happen silently again.

02

Offline is the default

The counter completes sales with the network down. Operations queue in a local outbox and sync later — idempotent and commutative, so two branches re-joining after an outage converge with no conflict resolution at all.

03

Every app is a fish in the river

POS is the first fish, not the whole river. Purchasing, receivables, reporting, label printing — each swims as its own app against the same operation log and the same native API, so the river grows without rewrites.

A native API, not an afterthought.

Every mutation is an operation in an append-only log, keyed by a client-generated ULID — replay it twice, it applies once. Device identity is a first-class credential: pairing, seat metering, remote revoke.

The same /v1 + /sync contract drives the web PWA, the Kotlin Android client, and whatever ships next — held together by shared conformance fixtures, not shared code.

{
  "deviceId": "dev_01J9K3…",
  "ops": [ {
    "opId":     "01JD8FZK7Q…",   // ULID — the idempotency key
    "type":     "sale.create",
    "branchId": "br_ravi_road",
    "clientSeq": 4182,
    "payload":  { "totalPaisa": 7785045, "lines": […] }
  } ]
}
→ 200  { "applied": 1, "duplicates": 0, "cursor": "…" }

Ask the ledger. Build on it.

Because every fact is a row in one append-only ledger, AI answers are grounded — every figure cites the movements it was summed from. Ask in your own language, typed or spoken, from any counter or the owner's phone.

And because every mutation is an operation on the native API, you can build with AI too: draft reports, reconcile stock, scaffold whole apps — agents act through the same op-log, the same permissions, the same audit trail as any user.