Please describe your proposed solution

We will develop an open-source library for multisignature (multisig) wallets on the Cardano blockchain. Our solution focuses on simplifying the complex process of creating, managing, and interacting with multisig wallets. Through this library, users will be able to:

• Create and manage multisig wallets with customizable signature requirements (M-of-N schemes, time locks, etc.).
• Construct, validate, and submit multisig transactions via simple REST APIs.
• Track transaction statuses and outcomes in real-time.

We will publish the library with documentation of usage and deployment methods for easy integration in projects.

Our approach leverages Cardano's native scripting capabilities to ensure compatibility, security, and decentralization. By focusing on native scripts, we avoid complexities associated with Plutus and keep the implementation light and performant for broader use cases.

This solution is designed to jumpstart development for anyone building on Cardano. A demo user interface will illustrate wallet creation and transaction management, lowering the entry barrier for new developers and businesses exploring the blockchain.

Our project is unique because it provides a lightweight, easy-to-integrate, and secure multisig wallet solution that can be adopted by wallets, DeFi platforms, and businesses needing sophisticated transaction authorization mechanisms without heavy custom development.

By empowering developers with these tools, we contribute to wider Cardano adoption, providing a crucial infrastructure component for enterprise-level blockchain solutions.

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

The open-source library will enable faster development of decentralized applications that rely on multisignature wallets, improving security and flexibility for Cardano users. By reducing development complexity, the library will foster more robust and secure dApps. The impact will be measured by adoption rates within the developer community and the number of projects that integrate the library into their solutions. Outputs will be shared through GitHub, developer forums, and the wider Cardano community channels.

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?

Our team has been actively developing on Cardano for the past 3 years and comprises a diverse group of highly skilled Cardano engineers, Senior software developers, and experienced Project managers. We have successfully delivered Cardano projects, both for clients and the broader ecosystem. Our capabilities include:

1. Cardano Integrations: We have experience in assisting clients with Cardano integrations, helping them build and deploy decentralized solutions on the blockchain.
2. Open-Source Contributions: We have developed multiple open-source libraries to support the Cardano developer community.

Our public GitHub repository: <https://github.com/lambdacc>

Catalyst track record: We have a proven track record with Catalyst-funded projects.

Fund-9: Completed: Open-source library for Plutus off-chain

Link to project repository: https://github.com/lambdacc/plutus-rest-wrapper

Fund-12: In-progress: CIP-1694 and Cardano Governance workshop

For transparency, the project repository will be open-source and publicly accessible throughout the project’s lifecycle.

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

Milestone 1: Architecture and documentation

Output:

1. Documentation of all supported multisig operations (wallet creation, transaction validation, submission, and tracking).
2. Architecture diagram outlining the technical design of the multisig wallet library.

Acceptance Criteria:

1. Documentation clearly outlines multisig wallet functionalities, including wallet creation, transaction flow, validation, and tracking, aligned with the project goals.
2. Architecture diagram provides a detailed and clear overview of system components, interactions, and data flows.

Evidence:

• Link to the public repository containing comprehensive documentation and architecture diagram in a downloadable format (.pdf).

Timeline: 2 weeks

Milestone 2: Wallet library with APIs published

Output:

1. A fully functional set of REST APIs for multisig wallet operations, including wallet creation, transaction management, and tracking.
2. Public-facing API documentation detailing how to use each endpoint with clear examples.

Acceptance Criteria:

1. APIs are functional, publicly accessible, and documented. Each API must have passing test cases.
2. API documentation contains clear usage instructions and example requests for each endpoint.

Evidence:

1. Link to Github repository for the wallet library.
2. Link to API documentation for all APIs in the library.
3. Links to test reports/screenshots and test transactions on a Cardano blokchain explorer.

Timeline: 8 weeks

Milestone 3: UI Integration

Output:

1. Sample User interface (UI) integrated with the wallet APIs, enabling interaction with all multisig wallet functionalities.
2. A user guide explaining how to use the UI to perform multisig wallet operations (creation, transaction management, etc.).

Acceptance Criteria:

1. A working UI demo that enables users to perform core wallet operations, integrated seamlessly with the REST APIs.
2. User guide published and clearly explaining how to use the UI, with step-by-step instructions.

Evidence:

• Link to Github repository containing the demo UI source code and the user guide (.pdf).
• Link to the public demo video showcasing the working UI.

Timeline: 6 weeks

Final Milestone: Project Close-Out Report and Demo Video

Output:

1. Detailed project close-out report, summarizing key learnings, challenges faced, and solutions implemented.
2. Demo video showcasing the full functionality of the multisig wallet library.
3. Final, updated documentation reflecting the finished project, including all changes made during development.

Acceptance Criteria:

1. Report includes lessons learned, key outcomes, and reflections on the success of the project.
2. Demo video presents a full demonstration of the library and API functionality.
3. Finalized documentation is publicly accessible and comprehensive.

Evidence:

1. Link to Github repository for the multisig wallet library and UI.
2. Link to close-out report (.pdf),
3. Link to closeout video

Timeline: 2 weeks

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

Our team, Lambdac, is an unincorporated volunteer collective comprising experienced Cardano engineers, Senior Software engineers and Project Managers, aiming to make meaningful contributions within the Cardano ecosystem. We have successfully delivered Cardano integrations for clients, Catalyst projects and open source libraries for the broader ecosystem. Our public GitHub repository: <https://github.com/lambdacc>

Here are the Catalyst projects we have received funding for in the past:

Fund-9: Open-source library for Plutus off-chain – Status: Completed

Link to project repository: https://github.com/lambdacc/plutus-rest-wrapper

Fund-12: CIP-1694 and Cardano Governance workshop – Status: In progress

Please provide a cost breakdown of the proposed work and resources

• Library Development: 20,000 ADA for building the multisig wallet library with APIs.
• UI Development: 10,000 ADA for the creation of a sample user interface.
• Testing and Documentation: 5,000 ADA for testing including bug bounty and documentation.
• Project Management: 2,000 ADA for coordination and progress updates.

Total: 37,000 ADA

No dependencies.

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

The development of this library will provide long-term value to the Cardano ecosystem by enabling dApp developers to integrate multisig wallets seamlessly. The requested budget is economical compared to the expertise required for the complexity of this project. The project’s open-source nature and reusability will provide a high return on investment for the community.