An alternative Rust node client for the Cardano blockchain. Aimed as an entrypoint for client applications initially, it aspires to become a full block-producing node running side-by-side with the Haskell nodes to further increase the decentralisation of the platform while fostering its rich open source ecosystem.
One of the core objectives is to achieve a full block-producing Rust Cardano node which can run side-by-side the existing Haskell nodes in a fully interoperable manner. The project is ambitious and spans over many areas such as networking, cryptography or language theory. It is developed from several parts each covering a different aspect of the node and its surrounding ecosystem.
Besides, Amaru is also geared towards developer experience and aims at providing easy to grasp interfaces using widely spread technologies such as gRPC while maintaining compatibility with the strong ecosystem of middlewares, such as Ogmios or Oura, that constitutes the backbone of Cardano services.
Project maintainers can come from PRAGMA member organizations or the broader community.
Matthias Benkort Technical Director @ Cardano Foundation 
Arnaud Bailly Technical Architect @ Cardano Foundation 
Pi Lanningham CTO @ Sundae Labs 
Damien Czapla Project Manager @ Open The Lead Amaru received ₳1,500,000 in Cardano Treasury funding through community approval in 2025 to establish the foundation for a block-producing Rust Cardano node. That work moved the project through chain synchronization, ledger state tracking, conformance testing, simulations, observability, peer-to-peer networking and relay-oriented behavior.
Early 2025 work continued ledger state tracking, stake distribution reconstruction, basic chain-selection behavior and simulation testing practices for Amaru.
The project advanced ledger-rule implementation, conformance testing and node-to-node behavior, with public demos showing the pieces coming together.
Amaru continued filling out chain synchronization, conformance tests, distributed tracing and consensus simulation work during the second node diversity workshop period.
The end of the 2025 funded phase emphasized the simulation and visualization pipeline, Amaru doctor, constrained deployments and public preparation for the next funded stage.
Amaru received ₳10,142,000 in Cardano Treasury funding through community approval in 2026 to advance the 2025 foundation toward relay capability, block production and mainnet readiness. The core development track covers relay wrap-up, hard-fork readiness, block-production work, security review and mainnet-readiness fixes.
The 2026 proposal begins with relay wrap-up, remaining ledger-rule stabilization, transaction diffusion, peer management, observability polish and readiness for expected protocol and Plutus changes.
Q2 focuses on the remaining functionality needed to move from relay behavior toward block production, including key management, block forging, mempool and peer-management work, conformance tests and the beginning of external security review.
Q3 is aimed at production confidence: security-audit completion, fixes requested by SPOs, performance tuning, monitoring improvements and zero unpatched major vulnerabilities or major defects.
Later 2026 work can evaluate protocol-level updates and future integrations, such as Peras, Phalanx, Leios or StarStream, where they fit Amaru's funded scope and technical readiness.
The 2026 proposal also funds work that makes Amaru easier to operate, test and understand outside the core engineering team. This includes constrained hardware, workshops, browser experiments, SPO-facing playgrounds, bug bounty work, financial audit, project management and communication.
Amaru's second funded proposal recognizes that an alternative node is only useful if it behaves correctly on the Cardano network and works with surrounding infrastructure. This track covers network behavior analysis, Antithesis support, Cardano-level testing and middleware integrations.
Amaru development has been supported through Cardano treasury funding for alternative node implementation work.
Current technical work is tracked through public GitHub milestones and treasury reporting.
PRAGMA supports Amaru through project governance, maintainer committee structure, reporting expectations, legal and operational support, and ecosystem coordination.
PRAGMA is not the treasury fund custodian and does not receive earmarked project donations for Amaru.
This demo showcases block propagation between a set of Amaru and Haskell nodes, with various topologies:
This demonstrates Amaru acting sometimes as an upstream peer, sometimes as a downstream peer while also performing chain selection. We also show to which extend the pipeline can be visualised in real-time through the tracing system.
In this recording, we go over the simulation and visualisation of the Amaru multi-stage execution pipeline.
Then, an overview of the latest version of Amaru doctor and the Pi deployment, as well as a sneak peek onto the brand new website at https://amaru.global.
The recording from the demo happening live at the end of the 2nd node diversity workshop in Toulouse.
The demo showcases the latest progress with the chain synchronisation and conformance tests, as well as an update on the consensus simulation and implementation.
A demo showcasing the latest progress on the ledger rules and the Rust-agnostic testing approach used for conformance. Then, we dive into some preliminary visualisation of the simulation engine, with auto-generated sequence diagrams and a terminal user interface that allows exploring execution traces.
Finally, another look at some of the Amaru metrics, obtained from running a cluster of Amaru nodes talking to one another. This demonstrates how our observability stack is particularly well suited for aggregating distributed traces from multiple processes.
First, an overview showcasing the latest progress on deterministically simulating the consensus, using pre-generated blockchain trees.
Then, a tour of the ledger rules and the separation of concerns between block validation and state management and how Amaru tackles this nicely.
Finally, an update on the ongoing work on the Peer-to-Peer (P2P) networking stack being designed not only for Amaru, but for the wider Rust blockchain ecosystem.
Three contributions covering:
Showcasing Amaru's on-disk ledger storage, solving a long-standing challenge of the Cardano node. The ledger state in this demo is comprised of the entire UTxO, stake pools parameters and registrations, rewards accounts and delegations. It is tracked throughout block application and persisted on-disk efficiently with regular snapshots at each epoch boundary.
While it doesn't yet calculate rewards at the epoch boundary, the on-disk state now contains all elements necessary to the calculation of rewards. It thus becomes the immediate next step.
A simple pipeline showcasing an Amaru node fetching blocks from the network, validating their header (VRF & KES) and forwarding them to an in-memory ledger performing UTxO management and phase-2 validations.