Introduction to Kairos Loan 🦅

Kairos Loan is a lending protocol using NFTs as collateral. Borrow instantly with the best market terms.

This book is a technical documentation of the protocol. It is meant for developers who want to integrate the protocol in their application or for people who want to understand more deeply how the protocol works.

If you would like to get started with Kairos Loan, you can visit our user guide or our website.

Explain like I'm 5

The Kairos Loan smart contract is used by NFT holders to securely borrow fungible tokens from lenders. The kairos smart contract keeps the NFTs of the borrowers in escrow during the time of their loans. To get its NFT back, a borrower has to repay its loan with interests. If it don't repay on time, the kairos smart contract sells the NFT and the proceeds of the sale go to the lender(s) of the loan. All loan terms are fixed and known at borrow time. The lender is the one providing loan offer(s) ahead of time for the borrower(s) to use. Lenders specify how much they are willing to lend, for how long and for which collatral (among other things) in their offers, as a way to control the risk they are taking by lending. Kairos does not guarantee that the collateral is not sold at a loss, loss that is assumed by the lender(s) of the corresponding loan. It is the responsibility of lenders to set their terms in a way that mitigate that risk. The kairos smart contract is meant to be used with an off-chain book of loan offers where the lenders are competing to provide the best terms for borrowers to pick.

Continue reading for a detailed overview of kairos mechanisms.


  • Lenders (also referred as suppliers) sign loan offers and provide kairos access to their ERC20 tokens.
  • Borrowers are NFT holders that let kairos take one or multiple of their NFTs in escrow as collateral to borrow ERC20 tokens from lenders.
  • Buyers (also referred as liquidators) buy NFTs from the kairos contract as part of the liquidation of loans that weren't repaid on time.
  • The administrator (also referred as the governance)can upgrade the kairos smart contract and access restricted methods controlling some protoco parameters.


Throughout this book, facts guaranteed by the kairos protocol are in bold italic. Auditors are encouraged to check them.