Access Patterns

About accesspatterns.dev

accesspatterns.dev is a place to learn DynamoDB by running it. Open the page and there's a real DynamoDB-compatible engine already loaded with a table, right in the browser tab. No AWS account, nothing to install.

DynamoDB is a brilliant database and a hard one to learn - it punishes the instincts you bring from SQL. You don't get it from reading; you get it from building a table, writing the items, firing the query and seeing what comes back. That needs an account or a local emulator, which is enough friction that plenty of people read about single-table design without ever building one. accesspatterns.dev takes the friction away: the database is in the tab.

What's in it

• A course of around twenty lessons, from your first GetItem to single-table design, each one something you build and run rather than just read.
• A handful of worked models to pull apart - a game leaderboard, a SaaS multi-tenant table - closer to what you'd actually ship than the usual textbook example.
• A full console: assemble any operation, fire it at the table, and lift the request straight out as JavaScript SDK v3, boto3 or AWS CLI code.

How it runs

It's built on Dynoxide, my DynamoDB engine, compiled to WebAssembly and running in a Web Worker in your tab. There's no backend - every query, scan and write runs client-side against a SQLite-backed store, which is why it needs no account and nothing to install.

It's a preview. The wasm build doesn't yet run against the conformance suite that holds Dynoxide's native build to real DynamoDB, so treat what you see as illustrative rather than authoritative. Building accesspatterns.dev on the engine is what's been hardening it, and getting the wasm build onto that suite is the next job.