Please describe your proposed solution.

Aquarium is our latest contribution to the Cardano ecosystem, following our noble mission to allow many new apps to leverage Cardano technology.

Before you learn about Aquarium Lambdas and Rules and how they revolutionize the dApps user experience, please take a look and feel free to play with our online working prototype on the Cardano Preview network: <https://dev.fluidtokens.com/aquarium> .

While the prototype allows a restricted amount of actions, it perfectly exemplifies how this solution works and proves it is completely feasible.

Aquarium Lambdas

The first part of our solution hides the blockchain complexity to revolutionize the regular user experience: it's a crucial step for Cardano adoption as user interactions on most successful platforms must be as simple as possible.

For example, if a marketplace wants to sell items in Stablecoins (USDM/USDA/iUSD/DJED/bridged USDC, etc.), its users shouldn't be required to also get and manage ADA tokens. Additionally, any Cardano token can be used instead of ADA to pay the fees.

The flow is the following:

1) Any dApp or project (here called "the Creator") that wants to allow its users to use feeless transactions creates a FeeTank

2) Only the Creator and the FluidTokens Validators Network will have access to the FeeTank

3) The Creator specifies the conditions to allow the use of the FeeTank during transactions such as whitelisted addresses, chain conditions, transaction content, etc.

4) The Creator adds a few lines of Lucid code in its platform to allow the users to use the gasless transactions

5) The FluidTokens Validators Network will ensure the use of the proper FeeTank and that the conditions are correctly met

6) The user will sign the transaction but won't pay any fee in ADA

Aquarium Rules

The second part of our solution allows projects to automate their Smart Contracts: dApps don't need to manage any complex infrastructure and this solution makes them crucially less centralized. DEXes, lending, renting, raffles, and many more Smart Contracts need this.

For example, a famous DEX leverages periodic transactions to batch the many users’ trading operations: this action is fully centralized as the DEX is managing it. Instead, the DEX could delegate this periodic set of transactions to the Aquarium Validators network to increase the decentralization level and to stop managing critical infrastructure off-chain.

The flow is the following:

1) The dApp (here called "the Creator") fills its FeeTank

2) The Creator creates an Aquarium Lambda (not usable by regular users)

3) The Creator specifies the conditions to trigger the Lambda (every x seconds, at chain event, with an external source of info, etc.)

4) The FluidTokens Validators Network will ensure to use of the proper FeeTank and that the conditions are correctly met

5) The FluidTokens Validators Network will execute the transaction for the Creator, resulting in true decentralized automation

An economically sustainable solution

Cardano Aquarium has the crucial role of guaranteeing a safe and decentralized way to allow fee-less transactions and to fully automate Smart Contracts.

To accomplish this, an open network of Validators will have the duty to submit the correct transactions with the correct values to the Cardano blockchain.

As compensation for their work, Validators are rewarded with a small fraction of the transaction fee cost, taken directly from the Creator's FeeTank.

Initially, Aquarium will work with a set of whitelisted Validators, then it will gradually expand the access to any node that wants to participate. Anyone will be able to become a node of this network by staking enough $FLDT (FluidTokens official token).

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

Our solution Aquarium brings many benefits to the whole Cardano Community:

1. Hiding the technology stack to the non-crypto user: a good user experience must hide all the technical details and let the user focus on the main purpose of the app, generating traffic/revenues. Web3 apps want to adopt safe solutions to make the experience easier, starting with removing the user obligation to pay fees in ADA when different currencies (like stablecoins, custom tokens, or even NFTs) are involved;
2. Removing the transaction fees to incentivize communities: any new project can attract users with a period of feeless transactions on its platform. This brings new users and makes the existing ones happier;
3. Decentralized automation of smart contracts: limit orders, take profits, stop loss, batchers, liquidation mechanisms, and more can finally be decentralized, removing the centralization level of some of the biggest Cardano applications.
4. New web3 use cases: with automatic smart contracts a lot of new projects can arise, with interesting new use cases that will enrich the Cardano ecosystem.

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?

We are 100% sure about the feasibility and our capability to deliver the whole project.

In typical web3 style, you don't have to trust us as the following points can be easily verified:

• FluidTokens is one of the leading DeFi ecosystems on Cardano
• No VC has ever been involved in FluidTokens, it's fully community-supported
• We have delivered innovative DeFi protocols (pool lending, renting, boosted staking) with a volume of 10+ million ada and current TVL of 2+ million ada
• FluidTokens has been online for almost 2 years without any security problem
• We are always focused on what the community needs to bring value to the Cardano ecosystem
• Our team has more than 15 years of software development experience
• The whole team has worked on many of the most important Cardano projects ever made
• Matteo Coppola (the author of this proposal) is a certified Cloud Architect and a senior Blockchain developer on both Ethereum and Cardano
• We deliver new protocols and solutions at unconventional speed, without sacrificing safety and the user experience
• Several Cardano projects are already interested in this proposed solution as it can improve their platform substantially
• Our standard development pipeline includes early feedback, conducting official auditing, ensuring scalability, code optimization, and docs generation
• FluidTokens also works with web2 enterprises to deliver web3 infrastructure and smart contracts, knowing their most common needs and difficulties.

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

Milestone: Format definition for Aquarium Lambdas and Rules; UI and SDK design for easy integration; infrastructure setup to support the full flow.

Acceptance criteria: Official format for writing conditions and triggers with Lambdas and Rules; UI design ready for frontend development; infrastructure High-Level Design diagram and deployment.

>Milestone: On-demand creation, refill, and withdrawal of FeeTanks.

Acceptance criteria: Backend, frontend, and on-chain components to properly create and manage FeeTanks.

>Milestone: On-demand creation, editing, and canceling of Lambdas and Rules.

Acceptance criteria: Backend and frontend components to properly create and manage FeeTanks.

>Milestone: Formalization and implementation of the Validators coordination algorithm.

Acceptance criteria: Docs and working environment of multiple Validators submitting user transactions.

>Milestone: The entire solution has been deployed on Cardano Preview/Preprod networks and it's being stress-tested by the community. Smart contracts auditing is in progress. Public docs are being written.

Acceptance criteria: The community is testing and giving feedback on the solution; auditing and public docs have started.

>Milestone: The entire solution has been deployed on Cardano Mainnet and it works smoothly. Initially, Aquarium will work with a set of whitelisted Validators, then it will gradually expand the access to any node that wants to participate. All tests (auditing included) have passed and the community can use the service from any device (mobile/browser).

Acceptance criteria: Fully working product on Cardano Mainnet; public docs available; stronger marketing about the solution to onboard the first big Cardano protocols that need it.

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

The whole FluidTokens team is involved in the realization of this solution.

In particular:

• Matteo Coppola: Cloud Architect, Backend and Smart Contract Developer
• Raul Antonio Rosa Padilla: Smart Contract Developer, Offchain integrations
• Ullas M.: Leading Frontend Developer
• Alberto Rizzi: Backend Developer
• Anastasia Polozova: Frontend Developer
• Henry Peters: FullStack developer
• Lorenzo Martani: Marketing

Please provide a cost breakdown of the proposed work and resources.

Infrastructure design and deployment: 8000$

Frontend development: 14000$

Backend development: 28000$

Smart contract development: 8000$

SDK creation: 1000$

Smart contract auditing: 35000$

Marketing: 5000$

Docs production: 500$

Formal, stress and quality testing: 500$

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

By allowing feeless transactions, custom fee transactions, and automatic Smart Contracts, the solution encourages new disruptive use cases of the Cardano platform. This leads to a more vibrant and active ecosystem, attracting more users, developers, and enterprises.

The overall value provided by the project justifies the investment. It creates new opportunities for projects and dApps, encourages platform usage, promotes standardization, and prioritizes security and user experience, all of which contribute to the long-term success of the Cardano ecosystem.