Smart Contracts¶

BPE is implemented as five Solidity smart contracts deployed on Base Sepolia (L2), built on top of the Superfluid Protocol's General Distribution Agreement (GDA).

Architecture¶

┌─────────────────────┐     ┌─────────────────────────┐
│  CapacityRegistry   │◄────│  StakeManager           │
│  ─ task type reg    │     │  ─ stake/unstake/slash   │
│  ─ sink reg         │     │  ─ capacity cap compute  │
│  ─ commit-reveal    │     └─────────────────────────┘
│  ─ EWMA smoothing   │
└────────┬────────────┘
         │ reads capacity
         ▼
┌─────────────────────┐     ┌─────────────────────────┐
│  BackpressurePool   │────►│  Superfluid GDA Pool    │
│  ─ rebalance()      │     │  (underlying primitive) │
│  ─ needsRebalance() │     └─────────────────────────┘
│  ─ pool per taskType│
└─────────────────────┘
         │
         ▼
┌─────────────────────┐
│  EscrowBuffer       │
│  ─ overflow hold    │
│  ─ FIFO drain       │
│  ─ B_max config     │
└─────────────────────┘

┌─────────────────────┐
│  Pipeline           │
│  ─ multi-pool chain │
│  ─ upstream prop    │
└─────────────────────┘

Contracts¶

Contract	Purpose
`CapacityRegistry.sol`	Task type registry, sink registration, commit-reveal capacity signals, EWMA smoothing
`BackpressurePool.sol`	Extends Superfluid GDA Pool with capacity-weighted rebalancing
`StakeManager.sol`	Stake management, capacity caps via \(\sqrt{\text{stake}/\text{unit}}\), slashing
`EscrowBuffer.sol`	Overflow buffer for when all sinks are at capacity, FIFO drain
`Pipeline.sol`	Multi-stage pipeline composition with upstream congestion propagation

Deployment¶

Contracts are deployed on Base Sepolia (testnet). Deployment addresses are tracked in contracts/deployments/base-sepolia.json.

Build & Test¶

cd contracts
forge build
forge test

All 40 unit tests pass. The test suite covers:

Capacity registration and EWMA smoothing
Stake management and capacity cap computation
Escrow buffer deposits and FIFO draining
Fork tests against live Superfluid on Base Sepolia

Source¶

Contract source code is in contracts/src/.