Multiplayer Demo Built with Elixir

In plain words

Supabase Realtime is a Change Data Capture server for PostgreSQL built with Elixir and Phoenix that broadcasts database changes to authorized clients via WebSockets. It uses PostgreSQL's logical replication to detect changes from Write-Ahead Logging files and converts them to JSON for real-time synchronization. The system includes security checks to ensure only authorized subscribers receive database updates, making it suitable for developers building multiplayer or collaborative applications.

written from the facts on this page · September 2026

From the sources

Realtime

In the maker’s words, at launch

Hey HN, I’m an engineer at Supabase [0] and one of the creators of this demo. My team and I have been working hard to bring developers the next version of Supabase Realtime. The current version of Realtime [1] is a Change Data Capture (CDC) server for a PostgreSQL database that broadcasts changes via WebSockets to…

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  Realtime Postgres2020 · github.com · ▲62

  Broadcast, Presence, and Postgres Changes via WebSockets - supabase/realtime

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  Realtime Multiplayer by Supabase2022 · multiplayer.dev · ▲273

  Easily build real-time apps that enables user collaboration

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  Supabase2024 · supabase.com · ▲2,325

  The Postgres developer platform is now generally available

• PS
  Peerdb Streams – Simple, native Postgres change data capture2024 · ▲177

  Hello HN, I am Sai Srirampur, one of the Co-founders of PeerDB. (https://github.com/PeerDB-io/peerdb). We spent the past 7 months building a solid experience to replicate data from Postgres to data warehouses. Now we're expanding to queues. PeerDB Streams provides a simple and native way to replicate changes as they happen in Postgres to Queues (Kafka, Redpanda, Google PubSub, etc). We use Postgres logical decoding to enable Change Data Capture (CDC). Blog post here: https://blog.peerdb.io/peerdb-streams-simple-native-postgres.... 10-min quickstart here:…

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  ElectricSQL, Postgres to SQLite active-active sync for local-first apps2023 · electric-sql.com · ▲617

  Hi HN, James, Valter, Sam and the team from ElectricSQL here. We're really excited to be sharing ElectricSQL with you today. It's an open source, local-first sync layer that can be used to build reactive, realtime, offline-capable apps directly on Postgres with two way active-active sync to SQLite (including with WASM in the browser). Electric comprises a sync layer (built with Elixir) placed in front of your Postgres database and a type safe client that allows you to bidirectionally sync data from your Postgres to local SQLite databases. This sync is CRDT-based, resilient to conflicting…

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  This is an experimental extension for CRDTs, pg_crdt: GitHub repo[0]. It supports Yjs/Yrs and Automerge. The linked blog post [1] describes how we're thinking about this extension in a Supabase context. I want to emphasise this part: "pg_crdt has not been released onto the Supabase platform (and it may never be). We’re considering many options for offline-sync/support and, while CRDTs will undoubtedly factor in, we’re not sure if this is the right approach." [0] GitHub repo: https://github.com/supabase/pg_crdt [1] Blog post:…

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