@byronwade/adapter-pglite

PGlite (Postgres-in-WASM) adapter for Fakebase — the highest-fidelity local backend.

PGlite embeds a real Postgres engine compiled to WebAssembly, so you get true Postgres semantics (the real parser, planner, jsonb, ilike, window functions, ordering with NULLS FIRST/LAST, …) with no native build step. Unlike better-sqlite3, it runs identically on macOS, Linux, and Windows, and in CI, without node-gyp.

⚠️ Fakebase is a local / dev-only tool for prototypes. It is not production infrastructure. See the security notes.

Install

pnpm add @byronwade/adapter-pglite @byronwade/client

@electric-sql/pglite is bundled as a direct dependency — there's nothing else to install.

Usage

import { createPGliteKernel } from "@byronwade/adapter-pglite";
import { createClient } from "@byronwade/client";
import { schema } from "./fakebase/schema";

// In-memory (great for tests): omit `dataDir`, or pass "memory://".
// Durable: pass a filesystem directory.
const kernel = createPGliteKernel({ schema, dataDir: ".fakebase/pg" });
const supabase = createClient(kernel);

const { data } = await supabase.from("notes").select("*");

createPGliteKernel is synchronous and mirrors createMemoryKernel / createSqliteKernel. The WASM Postgres boots lazily; the first query awaits readiness automatically, so you never need to await construction.

When to choose this adapter

| Adapter | Backing store | Native build | Best for | | ------------------------------ | ------------------- | ---------------- | --------------------------------------------- | | @byronwade/adapter-memory | JS objects | none | unit tests, throwaway demos | | @byronwade/adapter-json | JSON files | none | small durable prototypes, git-diffable data | | @byronwade/adapter-sqlite | SQLite (WAL) | better-sqlite3 | durable single-file persistence | | @byronwade/adapter-pglite | Postgres (WASM) | none | maximum SQL fidelity before real Supabase |

Behaviour & parity notes

To keep behaviour identical across all adapters (verified by the shared contract suite in @byronwade/test-utils):

• RLS is evaluated in JS via the shared PolicyEngine (not Postgres roles), matching the other adapters. It is an approximation — verify against real Postgres before relying on it.
• uuid and temporal columns are stored as text, so the adapter accepts the same lenient values as the others (e.g. non-UUID string ids, verbatim ISO timestamps).
• Column defaults (gen_random_uuid(), now(), literals) are applied in JS at insert time; foreign-key constraints are omitted.
• jsonb/json and boolean use their native Postgres types and round-trip losslessly.
• rpc() on the adapter throws a CapabilityError; database functions are served by the kernel's local function registry.

API

• class PGliteAdapter implements FakebaseAdapter — constructor takes { dataDir?: string } (filesystem path, "memory://", or omit for in-memory).
• createPGliteKernel({ dataDir?, schema?, storageDir? }) — a fully wired kernel (data + auth + storage + realtime + functions).

License

MIT