Last updated 7 months ago
Cardano’s DeFi is still early stage with TVL under $300M (<1% of Ethereum’s). It lags behind Ethereum and Solana, needing growth as ADA treasury funds shrink and fees alone can’t sustain it.
Building the ROSCA prototype on Cardano—a DeFi platform for savings and capital raising, offering interest-based returns that are flexible, scalable, and globally accessible for all users.
This is the total amount allocated to ROSCA: Decentralized Savings & Fund Pool utilizes Cardano-SC.
Please provide your proposal title
ROSCA: Decentralized Savings & Fund Pool utilizes Cardano-SC
Enter the amount of funding you are requesting in ADA
69000
Please specify how many months you expect your project to last
8
Please indicate if your proposal has been auto-translated
No
Original Language
en
What is the problem you want to solve?
Cardano’s DeFi is still early stage with TVL under $300M (<1% of Ethereum’s). It lags behind Ethereum and Solana, needing growth as ADA treasury funds shrink and fees alone can’t sustain it.
Supporting links
Does your project have any dependencies on other organizations, technical or otherwise?
No
Describe any dependencies or write 'No dependencies'
No dependencies
Will your project's outputs be fully open source?
Yes
License and Additional Information
Yes, the entire project will be released under the MIT License. The source code and datasets will be made public on GitHub from the first stages of the project.
Please choose the most relevant theme and tag related to the outcomes of your proposal.
DeFi
Describe what makes your idea innovative compared to what has been previously funded (whether by you or others).
Our ROSCA (Rotating Savings and Credit Association) model introduces innovation by combining the traditional community-based savings mechanism with blockchain-native features tailored to Cardano. While previous funded projects in Catalyst have focused on decentralized lending, staking pools, or microfinance solutions, none have explored a non-liquidation, collateralized ROSCA contract where participants secure their commitments with ADA or stablecoin in a risk-free structure.
Describe what your prototype or MVP will demonstrate, and where it can be accessed.
Our MVP is a ROSCA dApp on Cardano that enables users to form savings groups with trustless, collateralized commitments via smart contracts. Users contribute in cycles, receive payouts in turns, and provide ADA/stablecoin collateral. The MVP will run on Cardano testnet with open-source code and a demo UI accessible via GitHub and web app.
Describe realistic measures of success, ideally with on-chain metrics.
Success will be measured by the number of active users, completed ROSCA cycles, smart contract interactions, total ADA/stablecoin collateral committed, and group formations—all observable on-chain. We will also track payout history, and user retention via testnet explorer and analytics dashboards. Community feedback during MVP testing will provide additional qualitative metrics to assess usability and trustless functionality.
Please describe your proposed solution and how it addresses the problem
Explanation of the ROSCA model:
THE CONTRACT LOGIC IS IMPLEMENTED:

A: mobilized capital.
F: fixed monthly capital.
B: reverse auction price.

* Detailed Cycles and Actions:
-Month 1:
John needs money urgently, accepts 30% interest (3,000 ADA).
Cash Flow: Alice → 7,000 ADA → John.
Cash Flow: Bob → 7,000 ADA → John.
John receives total: 14,000 ADA.
-Month 2:
Bob needs money, accepts 25% interest (2,500 ADA).
Cash Flow: John → 10,000 ADA → Bob.
Cash Flow: Alice → 7,500 ADA → Bob.
Bob receives total: 17,500 ADA.
-Month 3:
Alice receives money at 0% cost (last-mover advantage).
Cash Flow: John → 10,000 ADA → Alice.
Cash Flow: Bob → 10,000 ADA → Alice.
Alice receives total: 20,000 ADA.
*Final Financial Summary:
Members Total Payouts Total Received Net Profit/Loss
John 20,000 ADA 14,000 ADA -6,000 ADA ❌
Bob 17,000 ADA 17,500 ADA +500 ADA ✅
Alice 14,500 ADA 20,000 ADA +5,500 ADA ✅
-Summary:
John: incurred the highest cost of early capital, so lost 30% of his total contribution.
Bob: made only a small profit, reflecting the average cost of capital over the period.
Alice: did not need to raise early, so made the highest profit (nearly 38%) – this is the privilege of the last.
*Please refer to the extended spreadsheet of the ROSCA model. This is a spreadsheet that shows the detailed data of the entire ROSCA model simulating a larger scale real-world problem: https://drive.google.com/file/d/1DAkp0UZGCXImuq0SD-a8iUpruzUaIZnS/view?usp=sharing
Explain the role of Smart Contracts that will operate the ROSCA model:
-Summary: Smartcontracts in the ROSCA model not only automate processes and ensure transparent execution, but also create a foundation for compact, secure, and flexible DeFi applications in the community.
*Uniqueness of the ROSCA:
• The combination of traditional model and modern technology: ROSCA is a rotating savings and borrowing model that has existed for hundreds of years in many cultures. However, because there are still many risk factors of this model in real life such as: the intermediary position of the treasurer will be the role of the person controlling the cash flow of the model and taking on the role of collection and disbursement for each cycle stage of the model, this shows dependence on a third party intermediary, and this is a very risky factor for participating members, potentially causing many factors that can cause damage to the assets of all members and destroy the overall structure of the model, the implementation of the model on the blockchain through Smart Contract - Cardano is a breakthrough, helping this model to operate for the first time in a decentralized, transparent and trustless manner among members.
• Smart integrated reverse auction mechanism: Different from traditional ROSCA models that divide shares in order or draw lots, this system integrates an automatic reverse auction mechanism (The discount value of each round will be provided by a random value provided by the Oracle), allowing those who need to raise capital to accept a higher interest rate, thereby increasing the return for the remaining members. This mechanism increases the efficiency of capital use and optimizes the benefits in the group.
• Financial discipline is guaranteed by smart contracts: Participation and maintenance of contribution obligations are no longer dependent on honor commitments, but are bound by self-executing contracts, eliminating the risk of the group's common treasurer breaking, leaving the group or cheating.
• Scalability and community financialization: With the coded logic, this model can be deployed to any community: from groups of friends (3-5-7-9-12 members per fund group and the time per cycle can be flexible), non-profit organizations, to self-operating DAOs. Users do not need in-depth financial knowledge, just need a Cardano wallet to participate and accumulate capital safely.
• Use pairs of the same type of value: Transactions and loans in ROSCA are made between value pairs of the same type such as ADA–ADA or stablecoin–stablecoin (USDM, USDA, Djed, etc.), which helps avoid the risk of exchange rate differences, thereby ensuring stability and ease of calculation for both the capital mobilization and accumulation roles.
• ROSCA diversifies Cardano’s DeFi ecosystem. Unlike most projects focused on AMM, lending/liquidation or yield farming, it introduces a new path: enabling long-term planning, accumulation and reinvestment through community finance, grounded in social structure and risk sharing—aligned with Cardano’s vision of financial inclusion.
Please define the positive impact your project will have on the wider Cardano community
The implementation of the ROSCA model on the Cardano blockchain platform not only brings value to individual users, but also creates a far-reaching positive consequence for the entire ecosystem:
• ROSCA is a decentralized finance (DeFi) application that is close to real life. Instead of approaching users with complex DeFi tools such as lending protocols or yield farming, ROSCA helps people who have never used blockchain to easily participate in a transparent savings - borrowing system, thereby expanding adoption for Cardano at the community, household, cooperative or small group level in developing countries.
• Programming ROSCA in the smart contract language on Cardano demonstrates the practical applicability of Cardano's financial infrastructure, while also motivating developers to explore Cardano's financial tools in the direction of "community finance", helping to diversify the dApps ecosystem that is currently biased towards high-tech products.
• ROSCA can become a template model for human-centric DeFi applications, helping Cardano affirm its mission of "blockchain for social good" in the era of sustainable finance.
• Increase transaction volume and total value locked in (TVL). The ROSCA model creates a regular and cyclical flow of transactions in the network, from periodic contributions from members to reverse auctions that distribute capital, contributing to increasing transaction volume and total value locked in (TVL) on the Cardano blockchain. This increase not only promotes liquidity and vitality for the ecosystem, but also increases transaction fees collected for the network, creating a sustainable source of revenue that helps improve long-term finances, supporting operating costs and developing Cardano infrastructure.
*Summary: ROSCA leverages blockchain to modernize a centuries-old financial model into a decentralized, secure, and accessible platform. Its implementation on Cardano not only expands real-world DeFi applications, but also aligns with Cardano’s mission of financial inclusion. By supporting this proposal, the community invests in a model that prioritizes sustainability, human-centered finance, and technical transparency.
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 consists of young, dynamic, eager to learn developers with extensive experience in the fields of financial modeling as well as focusing on researching real-life models to apply to Cardano in particular as well as blockchain technology and Smart Contract applications in general. With the experience of operating real-life financial models, we have had objective views as well as general assessments through the process of operating these models. From there, we can exploit all the advantages and disadvantages of the difficulties, challenges and barriers. With a practical approach, our team has built and designed the idea for this proposed model to optimally exploit the advantages of real-life models as well as handle as thoroughly as possible the risk factors in financial models with the technological solutions that Cardano brings.
• Our development team consists of developers with a solid grasp of basic and advanced knowledge of blockchain technology, programming, AI data analysis, and a special focus on the Cardano ecosystem. With practical experience through the positions of vCR, Moderator, and many contributions to many funds from Catalyst before and now, we have a deep insight into the Cardano ecosystem as well as the blockchain generations that exist and develop in the market, from which we can build highly effective proposals for the community as well as bring real values to the Cardano ecosystem.
• With extensive skills and experience in operating business and financial models, combined with the ability to analyze, program, apply technology through practical experiences and in-depth assessments from experts who accompany us, this will be the basis for us to be able to commit to the capacity to implement this project.
• Along with that, to enhance the feasibility of the project and trust from the community, we will combine with strict plans and solutions throughout the project implementation process.
*** We will establish a financial monitoring, reporting and control system to ensure the accurate and efficient use of funds, demonstrated through the following methods:
* Project budget management solutions:
• Budget planning: We will develop a detailed budget plan, outlining the allocation of funds for each project milestone and activity. This plan will be shared with stakeholders for review and approval.
• Milestone confirmation: Based on the monthly milestone confirmation by the milestone reviewer, funds will be disbursed based on the achievement of pre-determined milestones and outcomes. The use of funds will be divided into specific stages, ensuring that cash flow is controlled effectively and flexibly.
• Transparent reporting: Periodic financial reports will be prepared and shared with stakeholders, providing clear information on the financial status of the project. These reports will include details of expenses, income and any deviations from the budget. The project team is committed to not spending on items not included in the approved plan, and will not include any additional expenses.
• Legal and compliance: We will comply with all legal requirements and regulations related to financial management, ensuring proper governance and compliance throughout the project.
• Risk calculation: The total project capital includes the calculation of the conversion value in the worst case of strong market fluctuations while still ensuring the completion of the proposal. Since the price of ADA can fluctuate during the project implementation period, if the price decreases, we will have a backup plan to cover the core costs to ensure the project implementation process is completed. If we have a spare budget due to the increase in ADA price, we will commit to adding some functions for the next phase such as in case of additional budget, the team commits to coordinate with technical experts in the Cardano community and Catalyst dev to externally audit the entire ROSCA model and develop more features for ROSCA such as: ROSCA Reputation System (participant reputation scoring system), Analytics Dashboard (Comprehensive spreadsheet for the platform), Localization (Multi-language support for ROSCA), Multi-Group Management (Support users to participate in multiple pools).
*Summary: Through strong governance, real-time reporting, and milestone-based disbursements, we are committed to not only technical innovation, but also high standards of financial transparency and social responsibility.
Milestone Title
Research and Design the basic platform of the ROSCA system.
Milestone Outputs
Acceptance Criteria
Evidence of Completion
Delivery Month
2
Cost
12000
Progress
20 %
Milestone Title
Research participant roles to build user portraits.
Milestone Outputs
Acceptance Criteria
Evidence of Completion
Delivery Month
2
Cost
19000
Progress
50 %
Milestone Title
Research real-world uses and risks of smart contracts, with solutions for each scenario.
Milestone Outputs
Acceptance Criteria
Evidence of Completion
Delivery Month
2
Cost
19000
Progress
80 %
Milestone Title
Completed security policy for users, contract integrity, and UX/UI design.
Milestone Outputs
Acceptance Criteria
Evidence of Completion
Delivery Month
2
Cost
19000
Progress
100 %
Please provide a cost breakdown of the proposed work and resources
*Milestone 1: Research and design the basic platform of the ROSCA system (2 months)
-Research and design the ROSCA platform system (in basic form and Smart Contract integrated version).
-Develop preliminary sketches of the system architecture and the model's operation flow using Smart Contract logic.
-Analyze and outline specific operation flows for all participating users and possible scenarios during the operation of the Smart Contract.
*Details:
——Total: 12,000ada
——Estimate hours/person: ~320h
——Progress: 20%
*Milestone 2: Research participant roles to build user portraits (2 months)
-Conduct a survey and identify the psychology, analyze the actual needs and desires of users when participating in the ROSCA model (show the results by survey form based on 50 people).
-Build and design the wireframe system of the roles of all participants when interacting with the smart contract and the asset transfer process.
-Develop the user interaction flow and data processing flow.
-Completed structure of the entire ROSCA model combined with related tasks of all users.
*Details:
——Total: 19,000ada
——Estimate hours/person: ~320h
——Progress: 50%
*Milestone 3: Research real-life scenarios and solutions when applied to smart contracts and all possible risk scenarios on the contract (2 months)
-Results of analysis and evaluation of the advantages and disadvantages of the ROSCA model
-Analysis of real risk situations and solutions when applied to Smart Contracts
-Building and designing a risk handling system when operating the ROSCA model
-Completing the diagram and basic operating framework of ROSCA and risk handling options when affected by undesirable participant factors, ensuring the overall structure of the contract as well as preventing financial risks for all participants.
*Details:
——Total: 19,000ada
——Estimate hours/person: ~320h
—— Progress: 80%
*Milestone 4: Complete the security policy for the platform as well as users, the integrity of the contract structure and UI/UX design (2 months)
-Completed smart contract review, testing, and code audit for the entire contract using Lucid Test Suite or Marlowe Test Simulation and AI Data Analysis tools.
-Completed the ROSCA model operation process, auction, asset transfer process, user risk handling during operation.
-Proceed to launch the model on testnet.
-Completed a comprehensive user data security policy, clearly stating data collection, storage and usage activities.
-Completed UI/UX design for the platform on the ROSCA platform website.
*Details:
——Total: 19,000ada
——Estimate hours/person: ~320h
—— Progress: 100%
*Note:
*Total budget in ADA: 69,000 ADA.
How does the cost of the project represent value for the Cardano ecosystem?

Terms and Conditions:
Yes
*Mr. Vu Van Nam - Project Manager:
Credential ID: 62aabf58-6f41-4d14-8e29-dca4c236e9fc
Credential ID: 96b3a3c6-3ec2-42f3-91de-5988cd3608ab
Policy ID: 51964ec5764252718ddfe92a9145bf0d085b3a9d61c01fe9b0808635
Fingerprint: asset1u4dfl4psa6xnvtlr6lat6e3qvvssqza54hw9wn
Link: https://www.coursera.org/account/accomplishments/specialization/certificate/AOXJVU4J1OB4
*ROLES:
*Mr. Nguyen Van Tai - Product Analyst:
Credential ID: d5ceac97-d9ab-46f7-9167-b35a07d5c89c
Credential ID: 37bea67c-48b6-4d92-b918-e554be7d4430
Policy ID: 51964ec5764252718ddfe92a9145bf0d085b3a9d61c01fe9b0808635
Fingerprint: asset1h7fczhjcyndg6lwevh8xmphprr053xhf038znn
*ROLES: