INSSats

INSSats is the Bitcoin private pension you control, with human advisory and smart contract security. Your funds stay in multisig. It's the future of retirement, available today.

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Inspiration

INSSats was born from observing 7 critical problems with state pension systems like Brazil's INSS:

  1. Centralization and government deficit - Deficit-ridden governments that constantly print money devalue retirement assets
  2. Demographic crisis - Inverted age pyramid: fewer contributors for more retirees
  3. Lack of exit option - Mandatory contribution through taxes, no alternative
  4. Risk of fund misappropriation - Resources can be diverted for other political purposes
  5. Unethical use of resources - Your money finances projects contrary to your values
  6. Changing rules "mid-game" - Retirement age constantly changes
  7. Lack of personalized consulting - Nobody helps you plan adequately

The inspiration was to create a sovereign, transparent, and sustainable alternative using Bitcoin as a store of value and Simplicity smart contracts to guarantee immutable rules.

What it does

INSSats is a decentralized private pension platform built on Bitcoin (Liquid Network) that offers:

Three-Persona Architecture:

SAVER

  • Manages retirement via mobile app
  • Controls 100% of resources
  • Can make planned withdrawals (with 7-day timelock) or urgent withdrawals (with consensus)

BROKER (Consultant)

  • Offers personalized human consulting
  • Performs P2P exchange (BRL → L-BTC)
  • Validates urgent operations
  • Business model: 2-5% fee on deposits + optional consulting

VAULT KEEPER (Custodian)

  • In production: M-of-N multisig geographically distributed (e.g., 3-of-5 nodes)
  • Validates operation security
  • Publishes proof of reserves
  • Business model: 0.5-1% annually on AUM

Simplicity Smart Contract:

Flexible N-of-M multisig with different logic per operation type:

  • Planned operations: 1 signature + 7-day timelock + veto right
  • Urgent operations: 3-of-3 consensus (all parties) + urgent fee
  • Emergency veto: Any party can block suspicious operation

Configurable parameters at vault creation:

  • Broker and keeper fees
  • Timelocks (planned, urgent, key recovery, params change)
  • Urgent operation fees

How we built it

Technology Stack:

Layer 1 - Blockchain:

  • Liquid Network (Bitcoin sidechain with Simplicity support)
  • L-BTC ("Wrapped" Bitcoin with greater privacy)

Layer 2 - Smart Contracts:

  • Simplicity - Formal language with mathematical verification
  • SimplicityHL - High-level language (Rust-like syntax) that compiles to Simplicity

We implemented:

  • create_vault() - Vault creation with configurable parameters
  • deposit() - Deposit with automatic broker fee calculation
  • initiate_planned_withdrawal() / execute_planned_withdrawal() - Withdrawals with timelock
  • initiate_urgent_withdrawal() - Urgent withdrawals with 3/3 consensus
  • veto_operation() - Veto by any participant
  • collect_keeper_fee() - Proportional annual keeper fee collection
  • update_params() - Parameter updates with consensus and timelock

Layer 3 - Backend:

  • Rust for CLI and contract integration
  • PSET (Partially Signed Elements Transactions) to coordinate distributed signatures

Technical Challenges Overcome:

  1. Simplicity is pure functional - No mutable state, no loops, no side effects
  2. No floats - Balance and Fee calculation using basis points (250 bp = 2.5%)
  3. Block-based timelocks (not timestamps) - Liquid: 1 block = 1 minute
  4. Cryptographic validation - Schnorr signatures (BIP-340) via native jets
  5. Signature coordination - PSET flow to collect 3 geographically distributed signatures
  6. Integration between Green wallet (Kotlin) and Simplicity (Node)

Challenges we ran into

Simplicity learning curve

  • Completely new language, pure functional paradigm
  • Limited documentation, few examples available
  • Had to study original paper and source code

Pure functional language limitations

  • No mutable variables → All functions return new values
  • No loops → Limited recursion
  • No floats → Fee calculation with integers (basis points)

Distributed signature coordination

  • How to collect 3 signatures from participants in different locations?
  • Solution: PSET (Partially Signed Elements Transactions)
  • Challenge: Integrate PEBT with air-gapped cold storage

Balancing security and convenience

  • Users want easy access, but security requires friction
  • Solution: Timelocks for planned operations (7 days) + emergency veto
  • Urgent operations require 3/3 consensus

**Implementing in 40 hours (Satshack 2025)

  • Very ambitious scope
  • Had to prioritize: App, smart contract + web, leaving integrations for later

Calculating fees without losing precision

  • Simplicity operates with u32/u64, no decimals
  • Solution: Basis points (10000 bp = 100%)
  • Keeper fee prorated over time: (balance × fee_bp × blocks_elapsed) / (10000 × blocks_per_year)

Accomplishments that we're proud of

First decentralized private pension system in Simplicity

  • Nothing similar exists in the Bitcoin ecosystem
  • Real use case

Smart contract PoC

  • 5 main functions written
  • Vault creation and operations dipatch
  • Params and Veto logic working

Innovative security model

  • Asymmetric security: each persona has appropriate level
  • Saver: hot wallet (convenience)
  • Broker: air-gapped cold storage (MANDATORY in production)
  • Vault Keeper: M-of-N geographic multisig (maximum security)

Veto system that protects against all attacks

  • Compromised Saver → Broker/Keeper can veto
  • Compromised Broker → Saver/Keeper can veto
  • Compromised Keeper → Saver/Broker can veto
  • Collusion of 2 parties → Third party can veto

CLI, Web and Mobile interface

  • Contract creation with configurable parameters
  • Create vault, Deposit, planned withdrawal, veto operations

What we learned

About Simplicity:

  • Static analysis allows knowing execution cost before running
  • Formal verification offers mathematical proofs of correctness
  • Bounded execution eliminates infinite loop risk
  • Jets (native operations) are essential for efficient cryptography
  • SimplicityHL is crucial for productivity (pure Simplicity is too low-level)

About Bitcoin and Covenants:

  • Timelocks are fundamental for reversible operations
  • Multisig alone isn't enough - needs intelligent logic
  • PSETs are the solution for distributed signature coordination

About Pension Systems:

  • Global problem: almost all state systems are unsustainable
  • Demographic crisis makes pay-as-you-go models unviable
  • Individual capitalization + Bitcoin solves inflation + confiscation
  • Human consulting is essential (not just technology)

About Development:

  • Minimal viable scope is crucial in hackathons
  • Technical decisions need justification (we documented everything)

What's next for INSSats

Phase 1: Testnet (1-2 months)

  • Deploy on Liquid testnet
  • Closed beta with 10-20 early adopters
  • Pilot Broker certification program
  • External security testing

Phase 2: Mainnet Alpha (3-4 months)

  • Deploy on Liquid mainnet with capital limits (e.g., 0.01 BTC/user)
  • 5-10 certified Brokers operating
  • 1-2 institutional Vault Keepers

Phase 3: Advanced Features (6-12 months)

  • Integrated retirement simulator (calc.bitcoineracademy.com)
  • Automated dashboard with projections and charts
  • Reputation system for Brokers
  • Impact analysis of contributions and withdrawals

Phase 4: Scale (12+ months)

  • Remove capital limits
  • Expand to other countries (Argentina, Venezuela, Turkey)
  • Vault Keepers competing in open market

Long-term Vision:

  • Make INSSats the standard for Bitcoin private pension
  • Network effect: more Brokers/Keepers = more trustworthy
  • Bitcoin financial education for millions of people
  • Real and functional alternative to failed state systems

INSSats - Your Retirement, Your Rules, Your Bitcoin!

Built With

  • elements
  • kotlin
  • simplicity
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