Please describe your proposed solution

CL is an L2 inspired by, and interoperable with, the Bitcoin Lightning Network. For a customer to pay a merchant via CL there must be route of payment channels between them. Moreover, there must be enough capacity in the channels to route the payment.

In CL, channels are symmetric and can be managed by any type of node, and so in principle any participant can provide routing services. In practice, it requires additional properties such as sufficient capital, high reliability and availability. Network participants that use their capital and expertises to actively provide routing services are called Gateways.

Calvus is a node run by "Gateways". It is optimized to handle many channels in a highly efficient manner. This includes:

• Efficient multi-channel lifecycle management with smart tx composition
• Robust, reliable, and efficient service provision, including multi-hop routing
• Efficient capital allocation between channels with near term capacity predictions
• Configurable channel management policies for new channels fee and pledge calculations
• Payment traffic statistics, other nodes performance and "reputation" tracking.

At its core Calvus is an event processing engine interfacing with the L1, as well as a set of APIs both internal and external.

Please define the positive impact your project will have on the wider Cardano community

The Cardano Lightning project aims to be a core enabler of a scalable and efficient payment newtork on Cardano. Calvus, the proposed gateway node, is a critical piece of infrastructure that will make non-custodial, permisionless payments feasible for the Cardano ecosystem, by enabling the routing of payments between users.

Key Outcomes

• Enabling Routing for Cardano Lightning Network: The Calvus node is the core component that facilitates reliable, multi-hop payment routing (not pathfinding!). Making payments atomic, trustless, and cost-effective.

• Broader Merchant and User Adoption: Calvus hugely impacts end users and merchants by providing the infrastructure which allows them to transact without direct payment channel connections.

• Incenitivizing Gateway Operators: Gatway operators can expand their roles and revenue streams by providing payment routing services. This creates an incentive for existing operators to participate and further strenghtening the network.

• Gossiping,Pathfinding and Future Development: The Calvus node will be a foundation for future development of the Cardano Lightning Network, including gossiping, pathfinding, and encrypted routing in Phase 2.

Measuring Impact

• Quantitative Metrics: The success of Calvus can be measured by metrics such as the number of active gateway nodes, number of successfully routed transactions, transaction volumes, and adoption by merchants.

• Qualitative Impact: Feedback from gateway operators will also be crucial. Testimonials, ease-of-use reports, and adoption stories will provide insight into how well the solution addresses real-world needs.

What is your capability to deliver your project with high levels of trust and accountability? How do you intend to validate if your approach is feasible?

Capability

We are experienced team of Cardano developers (please check team information for more details).

We are are already working on the concept phase proposal for Cardano Lightning. This MVP proposal is a natural continuation of the above concept phase which will turn part of the design into the code.

We were experimenting with L2's on our own before as well:

• Dominic Algernon Wallis already prototyped in Aiken subbit.xyz which is related to this design phase but an independent micropayments proposal.

• Tomasz Rybarczyk is a core maintainer of Marlowe and a CIP contributor. Designed a micropayments capability in the context of Marlowe - the implementation is in the Marlowe Roadmap.

Development process will be public and open-source

Both the output and the development process will be public and open-source. This approach provides an easy way for the Catalyst team and the Cardano community to evaluate the progress at each step of the process.

We will form a working group around the idea and facilitate the discussion so everything will be transparent and easy to track on our pages: <https://github.com/cardano-lightning> and https://cardano-lightning.org

What are the key milestones you need to achieve in order to complete your project successfully?

Milestone 1: Research and Design

a. Milestone Outputs:

• Analysis of how existing event driven architecture handles distributed transactions, with a focus on failure and error handling
• Map out the event sources, including the L1 as well as internal and external APIs
• Comprehensive set of triggers and actions detailing how they work.
• Establish the appropriate stack for the node including the Cardano interface.

b. Acceptance Criteria:

• Research considers at least three examples and comments on: maturity; compares and contrasts its context from that of Calvus (for example, if the examples is on a different blockchain, how that impacts design.); provides some commentary on the stack.
• At least 5 triggers and actions with explanations.

c. Evidence of Completion:

• Report on research available on project github: <https://github.com/cardano-lightning/cardano-lightning>
• Design documents on triggers and actions available on project github**:** https://github.com/cardano-lightning/

Milestone 2: L1 Interface

a. Milestone Outputs:

• Monitoring and management capability for handling on-chain events.
• Surfacing of properties such as congestion.
• Implementation of core channel management features which will allow batching and resubmission in the case of rollback.

b. Acceptance Criteria:

• Documentation guide presenting usage of the CLI.
• Software is runnable via the CLI and provides logging/ notifications.

c. Evidence of Completion:

• Implementation and documentation available on project github: https://github.com/cardano-lightning

Milestone 3: Internal APIs: Channel Management Policies &amp; Automation

a. Milestone Outputs:

• Manage channel lifecycle operations through testnet tx submissions and command line interface (CLI).
• Policies for automatic and semi-automatic channel management, including fee and pledge calculations for new channels.

b. Acceptance Criteria:

• Channel management operations (open, close, add capacity etc) can be executed automatically based on configurable policies.
• Example configuration files and documentation explaining policy setup.
• Tests available and pass

c. Evidence of Completion:

• Implementation and documentation available on project github: <https://github.com/cardano-lightning/cardano-lightning>

Milestone 4: External APIs: Client and internode communication

a. Milestone Outputs:

• Spec and implementation of client facing APIs to coordinate the channel management.
• Spec and implementation of internode communication protocol for routing, channel operations, and status messages.

b. Acceptance Criteria:

• Client can setup, use, and close a channel with the Gateway.
• Two nodes can successfully communicate and step through channel lifecycles including routing.

c. Evidence of Completion:

• Implementation and documentation available on project github: <https://github.com/cardano-lightning/cardano-lightning>

Milestone 5: Actions and triggers

a. Milestone Outputs:

• Melding and unifying the of the three APIs.
• Implementation of actions and triggers.

b. Acceptance Criteria:

• Actions and triggers can be configured
• 'E2E' style tests for the actions.

c. Evidence of Completion:

• Implementation and documentation available on project github: <https://github.com/cardano-lightning/cardano-lightning>

Final Milestone: Documentation and Deployment Packaging

a. Milestone Outputs:

• Comprehensive and coherent documentation including guide on how to run Calvus.
• Deployment packages for Debian-based systems, static Linux binaries, and NixOS module.
• Final close-out report
• Final closeout video

b. Acceptance Criteria:

• Node software can be deployed on target systems using provided packages.
• Final closeout report is publicly available
• Final closeout video is publicly available

c. Evidence of Completion:

• Implementation and documentation available on project github: <https://github.com/cardano-lightning/cardano-lightning>
• Packages and binaries available for download and installation.
• Link to final closeout report
• Link to final closeout video

Who is in the project team and what are their roles?

Tomasz Rybarczyk

• Professional experience:
• Nearly 20 years of coding and software design.
• Tons of open source.
• Cardano experience: ~3 years
• Member of Marlowe Team
• Profiles:
• Github Profile
• LinkedIn Profile

Dominic Algernon Wallis

• Professional experience:
• Phd in geometric topology. Former Data scientist/ ML eng.
• 10 years in software development.
• Cardano experience: ~3 years
• Runs artisan dapp dev house, Kompact.io
• Profiles:
• Github Profile
• LinkedIn Profile

Nicolas Henin (Consultant/Reviewer)

• Professional experience:
• 15 years in software development.
• North American Start-ups operating in Health/Wearable, Ad and Fin Tech industry.
• Cardano experience: More than 3 years
• Delivered on Cardano Mainnet: ICO Mechanism, an audited Smart Contract for World Mobile
• Member of Marlowe Team
• Profiles:
• Github Profile
• LinkedIn Profile
• Core Maintainer of Marlowe

Please provide a cost breakdown of the proposed work and resources

M1: 10 days

M2: 15 days

M3: 15 days

M4: 15 days

M5: 10 days

M6: 5 days

Contingency: 5 days

-------------

Total: 75 days

Cost per day: 1875₳ (3.33 Ada / $) ~ 570$

Total: 75 * 1875₳ = 150000₳

No dependencies

How does the cost of the project represent value for money for the Cardano ecosystem?

The Calvus project is an essential part of the Cardano Lightning (CL) Network, offering a specialized gateway node that supports scalable, trustless, and cost-effective payments within the Cardano ecosystem. By funding Calvus, the Cardano community gains a robust routing solution, enabling efficient, multi-hop payments that reduce dependency on direct channel connections and thereby expand usability of the Cardano Lightning for end users and merchants.

Our team brings a unique combination of expertise, with years of experience in Cardano development, payment channels, and infrastructure engineering. The costings reflect standard rates for skilled blockchain developers and network engineers in Europe, ensuring that funds are allocated to experts capable of executing a highly efficient, specialized node. Calvus will deliver significant long-term value through reusable, scalable infrastructure designed for Cardano’s continued growth and integration into real-world financial networks.