# rheo v1.0.0 - Table of Contents

> Durable, searchable, replayable consumer-group semantics over storage systems (MongoDB, Redis Streams, PostgreSQL/SQLite via Ecto, Mnesia, ETS): leases, fencing, partitions, frontier, lag, replay, ops inspect, and a GenStage/Broadway producer.

## Pages

- Start
  - [Rheo](readme.md)
  - [LICENSE](license.md)
  - [Quick Start](quick-start.md)
  - [Public API (v1.0)](public-api.md)
  - [Changelog](changelog.md)

- Livebooks
  - [Rheo Livebooks](rheo_demo.md)
  - [Rheo Quickstart](quickstart.md)
  - [Rheo Concepts & Overview](concepts.md)
  - [Rheo Ops: inventory, lag, dead letters / DLQ](ops-livebook.md)
  - [Rheo LiveDashboard via Phoenix Playground](live_dashboard.md)
  - [Rheo Pipelines: GenStage, Flow & Broadway](pipelines.md)
  - [Rheo Backends: ETS, Mnesia, Mongo, SQLite, PostgreSQL, Redis](backends.md)

- Guides
  - [Configuration](configuration.md)
  - [Consumer Groups](consumer-groups.md)
  - [Enqueuing](enqueuing.md)
  - [Dequeuing](dequeuing.md)
  - [Replay](replay.md)
  - [Querying](querying.md)
  - [Partitions and lag](partitions-and-lag.md)
  - [Ops and observability](ops.md)

- Backends
  - [ETS](ets.md)
  - [Mnesia](mnesia.md)
  - [Mongo](mongo.md)
  - [Using Ecto](using-ecto.md)
  - [Redis](redis.md)
  - [Building your own backend](building-your-own-backend.md)

- Pipelines
  - [Broadway](broadway.md)
  - [GenStage](genstage.md)

- Upgrading
  - [Upgrading](upgrading.md)

- Design
  - [Architecture](architecture.md)
  - [Roadmap](roadmap.md)
  - [Design Tutorials](tutorials.md)

## Modules

- Facade
  - [Rheo](Rheo.md): Rheo provides durable, searchable, replayable consumer-group semantics over
storage systems.

- Consume
  - [Rheo.Broadway](Rheo.Broadway.md): Wiring between `Rheo.Producer` and [Broadway](https://hexdocs.pm/broadway).
  - [Rheo.Broadway.Acknowledger](Rheo.Broadway.Acknowledger.md): `Broadway.Acknowledger` that settles Rheo leases.
  - [Rheo.Consumer](Rheo.Consumer.md): OTP consumer behaviour for Rheo streams.
  - [Rheo.Group](Rheo.Group.md): Local OTP coordinator for one `{instance, stream, group}` triple.
  - [Rheo.GroupSupervisor](Rheo.GroupSupervisor.md): Dynamic supervisor for local `Rheo.Group` processes under one Rheo instance.
  - [Rheo.Producer](Rheo.Producer.md): `GenStage` producer that turns demand into Rheo leases.

- Values
  - [Rheo.DeadLetter](Rheo.DeadLetter.md): Portable dead-letter (DLQ) row for ops inspection.
  - [Rheo.Event](Rheo.Event.md): An immutable event stored in a Rheo stream.
  - [Rheo.Event.Lineage](Rheo.Event.Lineage.md): Standard metadata keys for event lineage and provenance.
  - [Rheo.GroupInfo](Rheo.GroupInfo.md): Group health snapshot for ops inspection.
  - [Rheo.Lag](Rheo.Lag.md): Per-partition and aggregate consumer lag.
  - [Rheo.Lease](Rheo.Lease.md): A temporary claim on an event for one consumer group.
  - [Rheo.Page](Rheo.Page.md): One page of query results with an optional continuation cursor.
  - [Rheo.Partition](Rheo.Partition.md): Partition routing helpers for multi-partition streams.
  - [Rheo.Query](Rheo.Query.md): Portable query against a Rheo event stream.
  - [Rheo.Settle](Rheo.Settle.md): Portable settlement result vocabulary and the runtime policy built on it.

- Backend
  - [Rheo.Backend](Rheo.Backend.md): Behaviour for Rheo storage backends.
  - [Rheo.Backend.Capabilities](Rheo.Backend.Capabilities.md): Typed backend capability declaration (ADR 023).
  - [Rheo.Backend.ETS](Rheo.Backend.ETS.md): In-memory ETS implementation of `Rheo.Backend`.
  - [Rheo.Backend.Ecto](Rheo.Backend.Ecto.md): SQL implementation of `Rheo.Backend` on top of a host-owned `Ecto.Repo`.
  - [Rheo.Backend.Mnesia](Rheo.Backend.Mnesia.md): Durable OTP `:mnesia` implementation of `Rheo.Backend`.
  - [Rheo.Backend.Mongo](Rheo.Backend.Mongo.md): MongoDB implementation of `Rheo.Backend`.
  - [Rheo.Backend.Redis](Rheo.Backend.Redis.md): Redis Streams implementation of `Rheo.Backend` (ADR 026).
  - [Rheo.Backend.Wakeup](Rheo.Backend.Wakeup.md): Optional hint that work may be available (ADR 025).

- Runtime
  - [Rheo.Application](Rheo.Application.md): OTP application entry for Rheo.
  - [Rheo.Backoff](Rheo.Backoff.md): Exponential backoff schedule shared by `Rheo.Group` and `Rheo.Producer`.
  - [Rheo.Clock](Rheo.Clock.md): Injectable clock used for lease expiry and event timestamps.
  - [Rheo.Clock.Frozen](Rheo.Clock.Frozen.md): Controllable clock for tests and demos.
  - [Rheo.Clock.System](Rheo.Clock.System.md): Wall-clock implementation of `Rheo.Clock`.
  - [Rheo.Id](Rheo.Id.md): Opaque identifier generation for events, leases, and consumer ids.
  - [Rheo.Inflight](Rheo.Inflight.md): Inflight-lease bookkeeping shared by `Rheo.Group` and `Rheo.Producer`.
  - [Rheo.Telemetry](Rheo.Telemetry.md): Thin helpers around `:telemetry` for Rheo operations.

- Ops
  - [Rheo.LiveDashboard.Page](Rheo.LiveDashboard.Page.md): Thin LiveDashboard page over Rheo inspect APIs (ADR 027).
  - [Rheo.Telemetry.Metrics](Rheo.Telemetry.Metrics.md): Optional `Telemetry.Metrics` definitions for Rheo (v0.10+ / ADR 027).

## Mix Tasks

- Ops
  - [mix rheo.bench](Mix.Tasks.Rheo.Bench.md): Runs a small relative benchmark against `Rheo.Backend.ETS`.
  - [mix rheo.dead_letters](Mix.Tasks.Rheo.DeadLetters.md): Lists dead-lettered deliveries (ops inspect, ADR 027).
  - [mix rheo.ecto.gen_migration](Mix.Tasks.Rheo.Ecto.GenMigration.md): Generates an `Ecto.Migration` in the host app that creates Rheo's tables.
  - [mix rheo.group_info](Mix.Tasks.Rheo.GroupInfo.md): Prints lag, inflight, and dead-letter counts (ops inspect, ADR 027).
  - [mix rheo.lag](Mix.Tasks.Rheo.Lag.md): Prints lag for a stream/group (ops inspect, ADR 027).
  - [mix rheo.streams](Mix.Tasks.Rheo.Streams.md): Lists registered streams for a Rheo instance (ops inspect, ADR 027).