Sky Protocol level 2—a Proof-of-Authority (PoA) Data Availability (DA) network for Cardano.

[GENERAL] Name and surname of main applicant

Gauthier Lamothe

[GENERAL] Are you delivering this project as an individual or as an entity (whether formally incorporated or not)

Entity (Incorporated)

[GENERAL] Please specify how many months you expect your project to last (from 2-12 months)

5

[GENERAL] Please indicate if your proposal has been auto-translated into English from another language

No

[GENERAL] Summarize your solution to the problem (200-character limit including spaces)

On Fund 12, we built a contract and a centralized off-chain infrastructure. On Fund 13, we will add a minimal decentralized network for the infrastructure with a fixed committee of DA validators.

[GENERAL] Does your project have any dependencies on other organizations, technical or otherwise?

No

[GENERAL] If YES, please describe what the dependency is and why you believe it is essential for your project’s delivery. If NO, please write “No dependencies.”

No Dependencies

[GENERAL] Will your project’s output/s be fully open source?

Yes

[GENERAL] Please provide here more information on the open source status of your project outputs

Project will use Apache License v2.0.

We believe open source to be a moral and strategic imperative for such a project.

[METADATA] Horizons

L2

[SOLUTION] Please describe your proposed solution

There is no good Data Availability Solution today for Side-Chains on Cardano:

• Applications can publish their data on-chain, but this is slow and expensive.
• Individual Applications can each roll their own Data Availability solution, but this requires more work, and in the end, the solution is only protected by as much capital as each individual application.
• Applications can try to use Celestia or EigenLayer or another Data Availability Solution that wasn't designed to work with Cardano, but it will require a lot of effort, and you have to trust these networks.

Sky Protocol will build a Data Availability Solution tailored to the needs to Cardano:

• We will publish data in a way that makes it easy for Plutus contracts to validate the data and to use it as part of Layer 1 contracts.
• Our network will be rooted in Cardano with its own Cardano-based token, which will require fewer trust assumptions than using other networks.
• Our network will allow many Cardano-based DApps to share the same Data Availability network and pool the costs of both software development and immobilized capital for validation of this network, as compared to each app building its own network.
• Our network will eventually sport additional censorship-resistant features: for instance, time-locked blinding of data so that committee members cannot selectively censor data.
• Our network will also eventually use RAID5-style coding of data so that committee members only each see a fraction of the data, and the whole data can be recovered with a 2/3 honest fraction of the committee members.
• Finally, our network will support DApp validation in both "optimistic" style through interactive games, and "pessimistic" style through zero-knowledge proofs.

Our approach will allow DApp developers to write either high-speed, low-latency DApps, or highly censorship-resistance, low-latency DApps, either way with high throughput and low-costs, all of it rooted on the Cardano blockchain.

To demonstrate our impact, we will show how such DApps can be easily made on Cardano using our infrastructure—thereby multiplying the utility of the Cardano network.

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

Our project enables scalable DApps on Cardano, something which isn't possible yet, bringing Cardano on par with other chains with Data Availability solutions. On top of that, we claim to enable that for low development costs for builders.

We also provide a Japanese translation of this proposal to have the greatest possible impact, since the largest, oldest Cardano community is in Japan.

[CAPABILITY & FEASIBILITY] 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?

In the past, our team has worked with IOHK to successfully port our Glow language to an early version of Plutus.

We have also developed the AVOUM concept for Account-style DApps on top of UTXO blockchains.

We previously were Catalyst grant recipients for work on Formal Verification for Glow and for a study of AVOUM on Cardano.

We have given talks at Cardano Conferences.

We also have worked with other blockchains and blockchain projects (Ethereum, Harmony One, Nervos, Laconic, Sequentia).

We have completed all of our milestones on time, so far, for our Catalyst Fund 12 project, which was the beginning of our work on building the data availability network on Cardano. 

We have also developed traction among the Cardano community, and we continue to do so. Relevant community growth metrics include

• More than 2,400 followers on X
• A Discord server with 650+ members and an active community
• A token sale that went to completion on Cardano thanks to our terrific supporters!

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

Milestone Title: “Milestone 1 - Centralized PubSub network for Data Availability”

Milestone Description: The first milestone is a centralized Data Availability server, that offers publication and subscription services, with fixed throughput limits and communication over a decentralized gossip protocol (e.g. libp2p). This will provide the skeleton for the coming decentralized service.

Milestone Deliverable: A specific commit of our GitHub repository that contains the code as well as a test script so that anyone can reproduce a test deployment of the centralized DA service and a battery of interactions with test clients both publishers and subscribers.

Acceptance Criteria: As per deliverable above.

Expected Cost: 40,000.000ADA

Delivery Month: December 2024

Completion %: 20%

Milestone Title: “Milestone 2 - Integration of the Centralized DA server with the Cardano Contract”

Milestone Description: This milestone demonstrates how the Centralized service integrates with the Cardano blockchain via a simplified variant of the smart contract that accepts a single signature rather than a MultiSig. Publishers and Subscribers can use smart contracts to drive payment of services using the DA. For instance, the DA can be used to publish triggers for atomic swaps.

Milestone Deliverable: A specific commit of our GitHub repository that contains the code as well as a test script so that anyone can reproduce a test deployment of the centralized DA service integrated with a test Cardano blockchain, wherein publishers and subscribers use publishing of data on the DA as a trigger for payment of an onchain smart contract.

Acceptance Criteria: As per deliverable above.

Expected Cost: 60,000.000ADA

Delivery Month: January 2025

Completion %: 50%

Milestone Title: “Milestone 3 - Aggregation of DA services in a MultiSig”

Milestone Description: This milestone demonstrates how an n-out-of-m signature of multiple uncoordinated DA servers can be used to attest publication of some data. In an actual deployment, this use case would provide a fallback kind of signature in case some DA validators fail to cooperate together towards a cheaper-to-verify consensus signature, as well as a fast path more expensive signature for DA users to prove availability with lower-latency than waiting for DA consensus.

Milestone Deliverable: A specific commit of our GitHub repository that contains the code as well as a test script so that anyone can reproduce a test deployment of a federated DA service with a Cardano smart contract relying on a simple n-out-of-m signature scheme, and a battery of interactions with test clients both publishers and subscribers.

Acceptance Criteria: As per deliverable above.

Expected Cost: 50,000.000ADA

Delivery Month: February 2025

Completion %: 75%

Milestone Title: “Milestone 4 - DA with Consensus MultiSig”

Milestone Description: This Milestone culminates in a demonstration of a Proof-of-Authority Data Availability Network. The DA servers generate a consensus with a unified MultiSig attestation of what was successfully published by the network.

Milestone Deliverable: A specific commit of our GitHub repository that contains the code as well as a test script so that anyone can reproduce a test deployment of a United DA service with a Cardano smart contract relying on the disjunction of the simple n-out-of-m signature scheme and more efficient united multisig, together with a battery of interactions with test clients both publishers and subscribers.

Acceptance Criteria: As per deliverable above.

Expected Cost: 50,000.000ADA

Delivery Month: March 2025

Completion %: 90%

Milestone Title: “Milestone 5 - Project Close-out Report with Video”

Milestone Description: This Milestone culminates in a demonstration of a Proof-of-Authority Data Availability Network. The DA servers generate a consensus with a unified MultiSig attestation of what was successfully published by the network.

Milestone Deliverable: Project Close-out Report and Video with demonstration.

Important Note on Scope and Deliverable : For this Catalyst Grant we will not be dealing with payment and scalability functionalities. 

Acceptance Criteria: As per deliverable above.

Expected Cost: 50,000.000ADA

Delivery Month: April 2025

Completion %: 100%

See Milestone 5

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

François-René Rideau, Chief Scientist and Lead Developer

https://www.linkedin.com/in/fahree

https://github.com/fare

https://twitter.com/phanaero

François-René has extensive experience building on Cardano.

François-René has been making programming languages and distributed systems usable for 25 years. Alumnus of the École Normale Supérieure, Former Senior Engineer at ITA Software, he also worked at Google and Bridgewater Associates. While working in the industry, he notably maintained and rewrote ASDF, the build system at the heart of the Common Lisp open source community; he also kept publishing academic papers and speaking at programming language conferences. 

Gauthier Lamothe, Chief Operating Officer

https://www.linkedin.com/in/gauthier-lamothe

Gauthier has participated in a few blockchain projects, for entities such as the Free Republic of Liberland (that recently started using Polkadot), and worked on decentralized justice systems, tokenization of governance, and of course crypto-currencies.

Alexander Smart, Chief Legal Officer

https://www.linkedin.com/in/alexandersmart

https://github.com/ChiLaBo

Alexander has always thought fast, but learned to think deep and sharp at UChicago. After studying law at Pepperdine, he spent nearly fifteen years guiding executives and decision makers through litigation, in matters ranging from shoplifting and speeding tickets to multi-forum international investment bank disputes. His practice honed his ability to quickly assimilate and master new information, and deliver that information clearly at any level of sophistication. Tiring of courthouses, he found his skills were readily applicable and desperately needed in the blockchain space. 

Peter Hubshman, Chief Financial Officer

https://www.linkedin.com/in/peterhubshman/

Peter is a finance and operations expert focusing on early round startups. With origins in private equity, fund management and leveraged buyouts, in the early 2000’s he operated Internet Real Estate Group, a Web 2.0 studio in Boston which successfully developed businesses including Creditcards.com; Phone.com; Luggage.com; Jeans.com and a dozen other early primary domain businesses. There, his pioneering team of engineers created some of the earliest successful affiliate marketing and advertising platforms on the Internet, and were early experts in search engine optimization. 

Zoe Braiterman, Technical Community Manager

https://www.linkedin.com/in/zoebraiterman/

https://github.com/zbraiterman

https://twitter.com/zbraiterman

Zoe Braiterman has experience ranging from cyber security, data science and system architecture to product development. Passionate about helping startups to scale, she also has experience as a teacher and business manager. Her work as a security consultant has included diversity and education initiatives in collaboration with UN Women, along with similar diversity leadership initiatives utilizing artificial intelligence and other technologies, and she brings her passion for change making and social impact to the Web3 space. 

Sheldon Hunt, Advisor

Head of the Cardano Ecosystem at Emurgo

https://www.linkedin.com/in/sheldonhunt

https://twitter.com/_MrHunt_

Chris Gianneloni, Advisor

Founder of Blink Labs

https://blinklabs.io/

Manuel Simoni, Developer

https://github.com/manuel-sky/

Yaroslav Kozhevnikov, Developer

https://github.com/p3rsik

Avatar Nick, Developer

https://x.com/theavatarnick

Founder of Saturn Swap, also providing the libraries we need in C# in order to be compatible with Hydra

[BUDGET & COSTS] Please provide a cost breakdown of the proposed work and resources

• 1 lead dev / project manager : 55K ADA
• 1 senior dev : 55K ADA
• 1 junior dev : 40K ADA
• Project-related fees : 30K ADA
• Operating fees : 20 K ADA

[VALUE FOR MONEY] How does the cost of the project represent value for money for the Cardano ecosystem?

The project will greatly enhance the scalability of the Cardano ecosystem, notably by allowing builders to create DApps that manipulate far greater volume of data than currently possible, at an affordable, business-relevant price.