Pylon vs. InstantDB
Instant Cloud is shutting down. Signups are closed, hosted apps stop on August 31, 2027, and the team has joined OpenAI — Instant stays open source but unmaintained, so your options are self-hosting a Clojure/JVM stack or moving. InstantDB and Pylon both center on local-first, optimistic sync; Pylon adds server functions, policies, SSR, and a managed cloud in one binary. Step-by-step move: docs.pylonsync.com/migrate/instantdb.
You want the purest client-side local-first DX, you like the InstaQL graph query language, your backend logic is light enough to live in permission rules and the client, and you have the operations appetite to self-host an unmaintained JVM + Postgres 16 stack now that the hosted option is ending.
You want server functions running in-process with your data, deny-by-default row-level policies, native React SSR, faceted search, or to self-host the whole thing as a single binary.
Architecture at a glance
| Pylon | InstantDB | |
|---|---|---|
| Shape | Full-stack framework | Client-leaning realtime DB |
| Server logic | In-process query / mutation / action | Rules + client; lighter server surface |
| Schema | TypeScript entity() | Typed schema + InstaQL graph queries |
| Access control | Row-level policies, deny-by-default | Permission rules |
| Native SSR | Yes — React in the same binary | Client-first; pair a renderer |
| Self-host | One binary on any Linux box | Clojure/JVM + Postgres 16, unmaintained |
| Search | Full-text + facets built-in | Query the graph yourself |
What both ship
- Local-first, optimistic writes that reconcile in the background
- Instant reactive queries over a live connection
- Typed schema as code
- Built-in auth and access rules
- Offline-capable clients
- React SDK
- Managed cloud option (Instant's ends August 31, 2027)
Where InstantDB wins
InstantDB's query language fetches deeply nested relational data in one declarative shape. Pylon has nested-relation reads via queryGraph, but InstaQL's graph DSL is more expressive for deeply nested, graph-shaped reads.
For apps whose logic lives on the client, InstantDB keeps setup small by putting schema, permissions, and queries mostly in the frontend.
InstantDB focuses on relational sync. Its smaller surface is easier to learn than a full framework when that is all you need.
Where Pylon wins
Pylon runs query / mutation / action in-process with ctx.db, ctx.auth, and validators. Payments, third-party calls, and privileged writes have a server-side home that shares a transaction with your data.
Row-level access rules live next to the schema and run on the hot path of every read and write, including sync subscriptions. Unguarded entities are default-denied; a linter flags them at dev startup.
Server-render your frontend from the same binary with file routing, <Link>, <Image>, metadata, streaming, and ISR. InstantDB is client-first and leaves rendering to you.
Add search: to an entity for full-text hits + live facet counts, and field.vector for built-in vector search — same binary. Deferred work runs through ctx.scheduler; multi-step durable workflows through ctx.workflows.
Run the whole stack on a VPS you control, or on Smallware. Instant's own self-host path is a Clojure/JVM server on Postgres 16 plus a reverse proxy and an email provider, and its cloud stops on August 31, 2027.
The full sync engine runs natively in Swift and stays at parity with the web client on iOS and Mac.
Moving from InstantDB
| InstantDB | Pylon |
|---|---|
| InstantDB schema | entity() definitions in TypeScript |
| Permission rules | policy() with boolean expressions |
| useQuery / InstaQL | db.useQuery("Entity", { where }) |
| transact / tx | mutation / action in functions/*.ts |
| InstantDB auth | Magic-link / OAuth / OIDC |
| Client-side logic | Move privileged logic into server functions |
For client-only apps that need InstaQL graph queries and frontend-defined permissions, InstantDB is leaner to adopt and more expressive for nested relational reads. Pylon adds surface area when you do not need server functions, SSR, or self-hosting.
Try Pylon for yourself.
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