AbsurderSQL: Taking SQLite on the Web Even Further

What if SQLite on the web could be even more absurd?

A while back, James Long blew minds with absurd-sql — a crazy hack that made SQLite persist in the browser using IndexedDB as a virtual filesystem. It proved you could actually run real databases on the web.

But it came with a huge flaw: your data was stuck. Once it went into IndexedDB, there was no exporting, no importing, no backups—no way out.

So I built AbsurderSQL — a ground-up Rust + WebAssembly reimplementation that fixes that problem completely. It’s absurd-sql, but absurder.

Written in Rust, it uses a custom VFS that treats IndexedDB like a disk with 4KB blocks, intelligent caching, and optional observability. It runs both in-browser and natively. And your data? 100% portable.

Why I Built It

I was modernizing a legacy VBA app into a Next.js SPA with one constraint: no server-side persistence. It had to be fully offline. IndexedDB was the only option, but it’s anything but relational.

Then I found absurd-sql. It got me 80% there—but the last 20% involved painful lock-in and portability issues. That frustration led to this rewrite.

Your Data, Anywhere.

AbsurderSQL lets you export to and import from standard SQLite files, not proprietary blobs.

import init, { Database } from '@npiesco/absurder-sql';
await init();

const db = await Database.newDatabase('myapp.db');
await db.execute("CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)");
await db.execute("INSERT INTO users VALUES (1, 'Alice')");

// Export the real SQLite file
const bytes = await db.exportToFile();

That file works everywhere—CLI, Python, Rust, DB Browser, etc.
You can back it up, commit it, share it, or reimport it in any browser.

Dual-Mode Architecture

One codebase, two modes.

• Browser (WASM): IndexedDB-backed SQLite database with caching, tabs coordination, and export/import.
• Native (Rust): Same API, but uses the filesystem—handy for servers or CLI utilities.

Perfect for offline-first apps that occasionally sync to a backend.

Multi-Tab Coordination That Just Works

AbsurderSQL ships with built‑in leader election and write coordination:

• One leader tab handles writes
• Followers queue writes to the leader
• BroadcastChannel notifies all tabs of data changes No data races, no corruption.

Performance

IndexedDB is slow, sure—but caching, batching, and async Rust I/O make a huge difference:

Rust From Ground Up

absurd-sql patched C++/JS internals; AbsurderSQL is idiomatic Rust:

• Safe and fast async I/O (no Asyncify bloat)
• Full ACID transactions
• Block-level CRC checksums
• Optional Prometheus/OpenTelemetry support (\~660 KB gzipped WASM build)

What’s Next

• Mobile support (same Rust core compiled for iOS/Android)
• WASM Component Model integration
• Pluggable storage backends for future browser APIs

GitHub: npiesco/absurder-sql
License: AGPL‑3.0

James Long showed that SQLite in the browser was possible.
AbsurderSQL shows it can be production‑grade.