Stellar Community Foundation logo
  • Get Started
  • Awards
  • Projects
  • Governance
icon-
Stellar Community Foundation logo
top-splatter

By Kyros OS

Kyros: Real-Time Tax Solvency on Stellar

SCF #41
$135.0K
Build
Community Vote
github-icon

Products & Services

Kyros OS is a Soroban-based financial operating system that automates tax solvency for the gig economy by bridging real-time fiat banking data with smart stablecoin vaults.

Smart Contracts: Two core Rust contracts (TaxVault and ComplianceController) manage the user's fiscal solvency directly on Stellar.

  • TaxVault: An isolated, non-custodial smart contract deployed for each user. It segregates VAT and Income Tax funds from daily spending, locking them in EURC until the official tax filing window opens. This prevents accidental spending of tax money.

  • ComplianceController: Acts as the on-chain logic layer. It validates the user's fiscal status, calculates the required provisioning ratio based on real-time invoicing data, and authorizes withdrawals only for tax payments to the Tax Authority.

Backend Services: A robust Python/Django architecture orchestrates the synchronization between Fiat Banking and the Stellar Network.

  • Banking Sync Engine: Connects with Plaid to monitor bank transactions in real-time. It detects income events and triggers the provisioning logic.

  • VeriFactu Compliance Engine: Manages invoice data integrity and generates the legally required cryptographic hash (chaining) for anti-fraud compliance (VeriFactu/TicketBai), storing metadata in PostgreSQL. (Note: Automated OCR processing via Google Vision AI is scheduled for MVP 2.0).

  • Settlement Service: Orchestrates the programmatic conversion of tax liabilities from Fiat to EURC via integrated Stellar Anchors, depositing the funds directly into the user's isolated Vault.

Oracle Integration: Integrates Plaid as a "Financial Oracle" to fetch real-time bank balances and transaction history. All sensitive financial data is processed in a compliant environment, while the resulting tax liability proofs are recorded on-chain.

Frontend Application: A React-based dashboard that visualizes the user's "Real Solvency" (Bank Balance - Tax Liability). Features include:

  • Live Tax Simulator: Updates Model 303 (VAT) and Model 130 (IRPF) estimates instantly.

  • Vault Monitor: Displays the on-chain balance of the Tax Vault locked in EURC.

  • Wallet Integration: Seamless connection with Freighter for signing Vault transactions during tax season.

Requested Budget

$135.0K

Traction Evidence

1. Validated Demand & Pre-Product Market Fit: We are currently running a "High-Touch Beta" with a select group of Spanish freelancers. Although the full automation via Soroban is in development, these users are already utilizing our core tax calculation engine to manage their quarterly obligations.

  • Utility: These users rely on Kyros to estimate their VAT (Model 303) and Income Tax (Model 130) liabilities, proving that our fiscal logic solves a critical pain point even without full automation.

  • Commitment: We have secured signed Letters of Intent (LOIs) and partnership agreements with these early adopters. They have committed to migrating to the fully automated Kyros OS upon mainnet launch, validating our pricing model and value proposition.

  • Evidence: Please verify the attached testimonials and signed agreements demonstrating user commitment here: https://drive.google.com/drive/folders/1KBTQER1AfW__mfYgm9mGau1Lwt2LVZw8?usp=sharing

2. Market Opportunity (The "Why Now"): Spain has over 3.3 million self-employed individuals (Autónomos) facing one of Europe's most complex and punitive tax systems.

  • The Problem: The average freelancer spends +15 hours/month on bureaucracy or pays ~€60-100/month for traditional gestorías that do not offer real-time solvency tools.

  • The Gap: There is no existing solution in the Spanish market that combines automated tax filing with programmatic fund segregation. Kyros OS fills this gap by preventing the #1 cause of business failure for freelancers: spending tax money by mistake.

3. Growth Potential: Capturing just 0.1% of the Spanish freelance market (3,300 users) represents an annual recurring revenue (ARR) potential of €1M+. Our pilot program proves that users are willing to switch from traditional legacy services to a tech-first approach. While our MVP targets freelancers, the presence of SMEs in our current beta cohort confirms the immediate potential to scale into the corporate sector. Capturing these entities post-MVP will exponentially increase the Total Value Locked (TVL) in our EURC smart contracts, as corporate tax obligations (Model 200) are significantly larger than individual ones.

4. Post-MVP Scalability: The SME (S.L.) Expansion While our initial focus is on freelancers (Autónomos), our core architecture is designed to scale into the Small and Medium Enterprise (SME/Sociedades Limitadas) market.

  • High-Value TVL: Corporate entities process significantly higher volumes of VAT and Corporate Tax (Model 200). Capturing this segment post-MVP will exponentially increase the Total Value Locked (TVL) in our EURC smart contracts.

  • Automated Treasury: We aim to evolve Kyros OS into a full-stack "Automated CFO" for companies, handling not just tax compliance but complete corporate treasury management via Soroban.

Tranche 1 (Deliverable Roadmap) - MVP

Focus: Establishing the secure foundation. Translating Spanish Tax Law (LGT) into Python algorithms and developing the Soroban permissioned architecture.

Soroban "Permissioned" Smart Contracts (Alpha)

  • Description: Develop the TaxVault contract in Rust with native "Compliance Hooks". Unlike standard DeFi vaults, this contract must include logic to restrict interactions solely to whitelisted wallets (KYC-verified), ensuring adherence to MiCA and AML directives from day one.

  • Measurement: Contracts compile to WASM. Unit tests confirm that non-whitelisted addresses cannot deposit or withdraw funds (simulating AML blocking). Code published to GitHub.

  • Budget: $12,000

Fiscal Logic Engine (Python Backend)

  • Description: "Codify" the complex Spanish Tax Regulations (Models 303/130) into a Python/Django processing engine. This involves translating legal text regarding VAT deductibility, proration rules, and IRPF brackets into deterministic algorithms that will govern the funds.

  • Measurement: A test suite of 20+ fiscal scenarios (e.g., "Freelancer in Prorata", "Intracommunity VAT") passing successfully against the engine's calculations.

  • Budget: $10,000

    Secure Data Infrastructure & DevOps

    • Description: Architect and deploy the "Data Sovereignty" environment on AWS/Cloud. Configure strict firewalls and encryption at rest (AES-256) to comply with GDPR requirements for handling banking data. Setup CI/CD pipelines for secure iteration.

    • Measurement: Production-ready backend environment live (accessible via API). Security headers and SSL encryption verified.

    • Budget: $5,000

Total Tranche 1 Request: $27,000

Tranche 2 (Deliverable Roadmap) - Testnet

Focus: Bridging the "Real World" (Banks/Tax Authority) with Soroban and fortifying the codebase with institutional-grade security before Mainnet.

Secure Financial Oracle (Banking Integration)

  • Description: Develop the secure "Bridge" that connects the Plaid API with the Soroban environment. This involves building a normalization engine that categorizes raw bank transactions into specific tax-deductible classes (e.g., separating "Personal Dining" from "Client Entertainment") to feed the tax calculation engine accurately.

  • Measurement: A video demo showing a real-time bank transaction appearing in the Kyros dashboard and being correctly categorized for tax purposes within <5 minutes.

  • Budget: $12,500

VeriFactu Cryptographic Module (Anti-Fraud Compliance)

  • Description: Implement the immutable invoice chaining algorithm required by the Spanish Anti-Fraud Law (VeriFactu). This module generates a unique cryptographic hash for every invoice, linking it to the previous one to prevent data tampering. This ensures the platform's output is legally valid for the Tax Authority.

  • Measurement: A script that generates a valid chained hash for a sequence of 10 invoices, verified against the official technical specifications.

  • Budget: $13,000

Advanced Security Implementation & Testnet Deployment

  • Description: Deploy contracts to Soroban Testnet with advanced security features: implementation of "Circuit Breakers" (emergency pause), rate-limiting to prevent fund drainage, and re-entrancy protection. Execution of comprehensive fuzz testing and threat modeling scenarios to ensure contract resilience.

  • Measurement: Smart Contracts live on Testnet. A "Security Stress Test Report" (Fuzzing results) published showing zero critical vulnerabilities.

  • Budget: $15,000

Total Tranche 2 Request: $40,500

Tranche 3 (Deliverable Roadmap) - Mainnet

Tranche 3 (Deliverable Roadmap) - Mainnet Launch, KYC Integration & Beta Pilot

Focus: Going live. Deploying the production infrastructure, activating the KYC/AML "Compliance Gate," and onboarding the first cohort of real users (SMEs & Freelancers).

[Deliverable 3.1] Production Infrastructure & Mainnet Deployment

  • Description: Deploy Smart Contracts to Stellar Mainnet with secure administrative controls (Multi-sig admin keys). Configure the high-availability AWS production environment with redundancy and automated backups to ensure 99.9% uptime during tax filing windows.

  • Measurement: Live Mainnet Contract IDs verified on Stellar.Expert. Production URL accessible publicly with SSL and security headers active.

  • Budget: $22,500

[Deliverable 3.2] Identity Verification (KYC/AML) & Whitelisting

  • Description: Integrate a third-party KYC provider (e.g., SumSub) to verify user identities before they can interact with the TaxVault. Implement the "Whitelisting Logic" in the frontend that blocks non-verified wallets, ensuring full compliance with MiCA and SEPBLAC regulations from Day 1.

  • Measurement: Video showing a non-verified wallet failing to deposit, followed by a successful KYC process allowing the deposit.

  • Budget: $20,000

[Deliverable 3.3] Closed Beta Pilot (The "40 Cohort") & Tax Export Validation

  • Description: Onboard the waiting list of 40+ users (Freelancers & SMEs) to the Mainnet application. Execute a full "Tax Provisioning Cycle" with real money. Generate valid tax export files (Models 303/130) ready for upload to the AEAT website.

  • Measurement: Anonymized report showing transaction volume on Mainnet from the pilot cohort. A video demonstration of a generated PDF tax model being successfully validated by the official AEAT validator tool.

  • Budget: $25,00

Team

Arturo Ferrandiz (Co-Founder & CEO): Leads business development and product strategy. A Law graduate from the University of Valencia, he has successfully navigated the Spanish regulatory landscape to launch the Closed Beta, securing the initial cohort of 40 active users and managing banking partnerships. LinkedIn: www.linkedin.com/in/arturo-ferrandiz-fernandez-521b083a2

Clement Essien (Co-Founder & CTO): A Columbia University graduate and former Machine Learning Engineer at JPMorgan, leads the general technical architecture and Full Stack development. He ensures the security of the banking data layer and oversees the blockchain integration strategy, coordinating the transition from Web2 to Web3. LinkedIn: (1) Clement Essien, Ph.D | LinkedIn Github: clemEssien (Clement)

Frederick (Blockchain Developer):Holds a dual degree in Computer Science and Business from the University of Vienna. Specialized in Blookchain and Smart contracts. He executes the smart contract development, specifically the logic for the 'Tax Vaults', and handles the technical integration with Stellar Anchors under the CTO's supervision. Github: Fredibau (Frederik Bauer)

middle-splatter
Clement

Clement

github-iconlinkedIn-icon
Frederik-Bauer

Frederik Bauer

Arturo

Arturo

x-iconlinkedIn-icon

Project Stats

Team Size
3
Category
End-User Application
Total awarded
$0*
Awarded Submissions
0

Other Submissions

No other submissions.