phoenixframework/phoenix_pubsub

This system is a distributed real-time communication library that provides PubSub messaging and presence tracking capabilities. It enables applications to broadcast messages across clustered nodes and track the state of connected clients using causal vector clocks and delta replication for efficient synchronization. The implementation relies on Erlang's Registry and PG modules for process management and includes comprehensive tooling for testing distributed behaviors.

5 changes.

The project removed the Phoenix.Presence module and its associated tests, while renaming the package to Phoenix.PubSub and upgrading to version 2.3.0. This period involved migrating to a newer configuration system, raising the minimum Elixir requirement to 1.13, and adding ExDoc tooling for documentation generation.

8 changes.

This period focused on introducing and refining Phoenix.PubSub and Phoenix.Tracker to support distributed real-time communication and presence tracking. The work involved refactoring the PubSub backend to use Erlang's Registry and redesigning the Tracker internals with causal clocks and delta replication for improved consistency and performance. Comprehensive test suites and benchmarking tools were added to validate the new distributed protocols and ensure reliable behavior across cluster nodes.

A new \script/bench.exs\ script has been added to allow users to run simple benchmarks for merge operations. The script measures performance for creating sets, extracting state, merging sets, retrieving data by topic or PID, compacting state, and handling replica down events, with configurable set and delta sizes via command-line arguments.

script · high confidence

Added the Phoenix.PubSub module as a realtime publisher/subscriber service with support for PG2 and Redis adapters, including safe pool size migration and configurable dispatching. Added the Phoenix.Tracker module to provide distributed presence tracking using a heartbeat protocol and CRDTs, allowing applications to track and replicate presence information across a cluster with configurable callbacks for handling diffs and info messages.

lib/phoenix · high confidence

The \Phoenix.Presence\ application, along with all its supporting modules (\Adapter\, \NodeChecker\, \Registry\, \Server\, \Spawner\, and \Tracker\), has been removed from the codebase. This eliminates the existing presence tracking functionality, including node monitoring, state transfer, and pubsub-based presence events, meaning applications can no longer use this module to track connected users or devices.

_lib/phoenix\presence · high confidence

The Phoenix PubSub implementation has been restructured to rely on Erlang's Registry for process tracking, replacing the previous internal mechanism. This change introduces a new \:group\_by\ option (\:pid\ or \:key\) to control Registry sharding strategies and supports both the modern \:pg\ module and the legacy \:pg2\ module depending on availability. The PG2 adapter now supports separate \:pool\_size\ and \:broadcast\_pool\_size\ configurations to allow safe migration, and the system enforces that \:pool\_size\ is greater than or equal to \:broadcast\_pool\_size\. Additionally, the adapter protocol now requires implementing a \child\_spec\ callback, and the supervisor ensures the required Erlang/OTP version (21.3+) is present.

lib/phoenix/pubsub · high confidence

The \Phoenix.Tracker\ internals have been rewritten to improve consistency and performance in distributed environments. The system now uses a shard-pool architecture (\Phoenix.Tracker.Shard\) to manage state, replacing the previous monolithic design. Replication between nodes is handled via causal vector clocks (\Phoenix.Tracker.Clock\) and incremental delta generations (\Phoenix.Tracker.DeltaGeneration\), allowing nodes to sync only the changes since their last known state rather than transferring full state. Replica health is tracked with heartbeat-based status updates (\Phoenix.Tracker.Replica\), including support for permanent down detection to prune stale data. Additionally, a new \Phoenix.Tracker.ShutdownHandler\ ensures graceful state replication during node shutdown, and new API functions \get\_by\_key\ and \dirty\_list\ provide more granular access to tracked presences.

lib/phoenix/tracker · high confidence

The project has removed the \config/config.exs\ file, which previously handled application configuration using the deprecated \Mix.Config\ module. This change eliminates the legacy configuration mechanism, likely as part of a migration to a newer configuration system or to clean up unused configuration files.

config · high confidence

Added comprehensive test suite for Phoenix.Tracker internals; Added distributed test support helpers; Added shared PubSub adapter test suite; Added tests for PubSub and Tracker components; Removed adapter tests for Phoenix.Presence; Test suite now spawns clustered Phoenix PubSub nodes.

The project has been renamed from Phoenix.Presence to Phoenix.PubSub and bumped to version 2.3.0. This update raises the minimum Elixir requirement to 1.13, removes the dependency on the Phoenix web framework, and adds ExDoc (along with its dependencies like Earmark and Makeup) for documentation generation. The application module has also been updated to Phoenix.PubSub.Application, and the package metadata now includes source URLs and maintainer information.

(dependencies) · high confidence

Written by watchdog.canine.dev from the codebase's own history, inside the signed delivery this page is composed from.

• CAI 64 → 65 (+0.6)
• Rubric changed (rubric-2026.09.15 → rubric-2026.10.1) — scores are not directly comparable.

• Code Health 98 → 98 (+0.0)
• Architecture 99 → 99 (+0.2)
• Maturity 43 → 43 (+0.0)
• Readiness 67 → 69 (+2.4)
• Security 100 → 100 (+0.0)

• Documentation: no architecture or design documentation (README.md)
• Documentation: no usage examples (README.md)

Written by watchdog.canine.dev from the codebase's own history, inside the signed delivery this page is composed from.

phoenixframework/phoenix_pubsub was measured the same way every project in this corpus was: the same rubric, at a pinned commit, with the result published in full. Point a surveyor at a repository you know and see whether you agree with it.