User Guide

For developers building applications on top of ZeroDDS. Eight-section condensed handbook.

What is ZeroDDS

Pure-Rust implementation of the OMG Data Distribution Service. Wire-byte-identical to Cyclone DDS, OpenDDS, Fast DDS, RTI Connext on RTPS 2.5. Comes with bridges to MQTT, AMQP, CoAP, gRPC, CORBA, ROS-2, WebSocket and bindings for nine languages.

Install

For the 1.0.0-rc.1 release-candidate phase the supported install paths are:

# 1. Cargo (any platform with rustc 1.88+)
cargo add zerodds-dcps zerodds-rtps zerodds-discovery

# 2. Build from source
git clone https://github.com/zero-objects/zero-dds
cd zero-dds && cargo build --release

# 3. Pre-built CLI binaries — coming with the rc.1 binary release
#    (Homebrew tap, APT/DNF repos, MSI, Scoop, AppImage, Docker
#    multi-arch). See "Distro & native installer roadmap" below.

Distro & native installer roadmap

Native installers and distro repos roll out in stages. Track progress on the project's GitHub releases page.

Channel	Stage	Status
crates.io (`cargo install / cargo add`)	1	publishing in progress with the rc.1 tag
GitHub Releases (static binaries, AppImage)	1	built by the rc.1 release pipeline
ghcr.io multi-arch Docker	1	built by the rc.1 release pipeline
Homebrew tap (`zero-objects/homebrew-tap`)	2	tap repo published with rc.1; `brew tap zero-objects/tap && brew install zerodds`
Scoop bucket (`zero-objects/scoop-bucket`)	2	bucket repo published with rc.1
Arch User Repository (AUR)	2	PKGBUILD submission targeted for rc.1
Self-hosted APT repo (`packages.zerodds.org`)	2	signed `.deb` packages, GPG key on the website
Self-hosted RPM repo	2	signed `.rpm` packages on the same domain
Ubuntu PPA (Launchpad)	3	after rc.1 stabilises
Fedora COPR	3	after rc.1 stabilises
Chocolatey community feed	3	after rc.1 stabilises
Debian official, Fedora official, Homebrew core	4	long-lead; targeted post 1.0 stable

First Pub/Sub

Publisher:

use dds_dcps::{Factory, QosProfileBuilder};

let factory = Factory::default();
let participant = factory.create_participant(0)?;
let topic = participant.create_topic::<String>("Greetings")?;
let publisher = participant.create_publisher()?;
let writer = publisher.create_writer(&topic, &QosProfileBuilder::reliable())?;

writer.write(&"Hello, DDS!".to_string())?;

Subscriber pattern is symmetric. Full 15-chapter walk-through with cross-language ports lives in examples/tutorials/dds-chat.

QoS Cheatsheet

Policy	One-line
`Reliability`	`Reliable` retransmits lost samples; `BestEffort` drops them.
`Durability`	`Volatile` (no replay); `TransientLocal` (writer cache replay); `Transient`; `Persistent`.
`History`	`KeepLast(n)` per instance vs. `KeepAll`.
`Deadline`	Maximum interval between samples per instance; missed deadlines fire a status.
`Lifespan`	How long a sample remains valid after publication.
`Liveliness`	`Automatic` (DCPS-managed) vs. `Manual` (application asserts).
`Ownership`	`Shared` (multi-writer) vs. `Exclusive` (highest-strength wins).
`ResourceLimits`	Max samples / max instances / max samples per instance caps.
`DestinationOrder`	`ByReceptionTimestamp` vs. `BySourceTimestamp`.
`ContentFilter`	SQL-like filter on the subscriber side.

Bridges

Pick the bridge for your protocol:

Bridge	Use case
`zerodds-ws-bridged`	WebSocket clients, browser SPAs.
`zerodds-mqtt-bridged`	IoT MQTT broker integration.
`zerodds-coap-bridged`	Constrained-device CoAP.
`zerodds-amqp-bridged`	RabbitMQ / ActiveMQ enterprise queueing.
`zerodds-grpc-bridged`	gRPC service-mesh integration with auto-generated services per topic.
`zerodds-corba-bridged`	Legacy CORBA mainframes (financial-industry drop-in).
`zerodds-ros2-shim`	ROS-2 RMW plugin (REP-2007 / 2008 / 2009).

Security

Two layers:

DDS-Security 1.2 — OMG plugins enabled via Participant QoS. Auth + AccessControl + Crypto + Logging + DataTagging.
bridge-security — TLS 1.3 (rustls), bearer / JWT-RS256 / mTLS / SASL-PLAIN, ACL with wildcard + group matching, SIGHUP cert rotation.

Troubleshooting

Discovery silent — check that multicast is enabled on your network. Use zerodds-admin discovery snapshot to capture SPDP/SEDP traffic.
Sample lost — verify Reliability=Reliable on both writer and reader. BestEffort drops on congestion.
Wire-incompat with another DDS — capture both sides with tcpdump -i any -X port 7400 and diff.
Cross-language struct mismatch — regenerate code with idlc from a single canonical IDL.
TLS handshake fails — check ALPN protocol matches; mTLS requires the client cert chain rooted in the server's CA.

Spec Mapping

Which OMG spec covers which feature:

Pub/Sub API — DDS-DCPS 1.4 §2.2.
Wire format — DDSI-RTPS 2.5 + DDS-XTypes 1.3 (XCDR1/XCDR2).
Type system — DDS-XTypes 1.3 + IDL 4.2.
Security — DDS-Security 1.2.
QoS XML — DDS-XML 1.0.
Constrained devices — DDS-XRCE 1.0.
RPC — DDS-RPC 1.0.

Full handbook on GitHub →