Tech Hub

Technical documentation for developers building on or integrating with Fira Protocol — a modular fixed-rate and variable-rate lending infrastructure on Ethereum.

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Protocol Primer

Explore

Features

Fixed-rate lending, variable-rate lending, BT/CT/FW tokens, AMM, rehypothecation, and liquidity injection

Architecture

System layers, module dependencies, reentrancy, access control, and upgradability

Smart Contracts

Protocol contracts, token contracts, utility contracts, oracles, and math libraries

User Flows

Step-by-step transaction flows for borrowing, lending, LPing, and trading

Deployment

All mainnet addresses, market IDs, oracle pipelines, router facets, and key roles

Events & Indexing

On-chain event reference and position measurement methodology

Integrations

Interfaces and integration patterns for building on Fira

Security & Audits

Security design principles, six independent audits, and bug bounty

Quick Reference

Resource	Link
Mainnet Contracts	Deployment
Source Code	github.com/usual-dao/fira
Lending Market Source	github.com/usual-dao/fira-lending-market
Bug Bounty	Sherlock Program
Glossary	Developer Glossary
Whitepaper	Fira Whitepaper

Key Facts

Parameter	Value
Chain	Ethereum Mainnet
Router	0xFF615E63aAF2d1B1EE4AdFD34a5840747185d8A0
FW-USDC	0x62F5366C9E21A95326C461a098a408e034e017b3
BT Expiry (V1)	May 7, 2026 · May 27, 2026 (USDG)
Fixed-Rate Collateral	PT-USDe, PT-sUSDe, PT-USDG
Variable-Rate Collateral	wstETH, cbBTC
Audits	6 independent external + internal review