DeFi on TON

Decentralized Finance (DeFi) on TON is a growing ecosystem of financial applications that operate without intermediaries. You can swap tokens, provide liquidity, lend assets, and earn yield — all through smart contracts on the TON blockchain.

The integration with Telegram makes TON DeFi more accessible than other chains, but this accessibility also means less experienced users are exposed to real financial risks. This tutorial focuses on understanding those risks.

Decentralized Exchanges (DEXs)

DEXs allow you to swap one token for another without a centralized intermediary:

  • STON.fi: The largest TON DEX. Uses an automated market maker (AMM) model with liquidity pools
  • DeDust: The second largest DEX. Offers both volatile and stable swap pools with optimized routing
  • How swaps work: You trade against a liquidity pool (a smart contract holding two tokens). The price is determined by the ratio of tokens in the pool
  • Slippage: Large trades can move the price against you. Always set a reasonable slippage tolerance (0.5-1% for stable pairs, 1-5% for volatile)

Liquidity Provision

You can earn fees by depositing tokens into DEX liquidity pools:

  • How it works: Deposit equal value of two tokens into a pool. You earn a share of trading fees proportional to your share of the pool
  • LP tokens: You receive LP (Liquidity Provider) tokens representing your position. These can be redeemed for your share plus earned fees
  • Typical APR: 5-50%+ depending on the pool and trading volume
⚠️
Impermanent loss is real

When the price ratio of your deposited tokens changes, you suffer "impermanent loss" — you end up with less value than if you had simply held the tokens. The more volatile the pair, the greater the risk. This loss becomes permanent when you withdraw.

Lending and Borrowing

TON's lending ecosystem is still maturing. Protocols like Evaa allow:

  • Lending: Deposit tokens to earn interest from borrowers
  • Borrowing: Provide collateral and borrow other assets
  • Liquidation risk: If your collateral value drops below the required ratio, your position is liquidated (sold at a discount) to repay the loan

Smart Contract Risks on TON

TON's asynchronous, message-passing architecture creates unique smart contract vulnerabilities:

  • Bounce handling bugs: When a message to a contract fails, a bounce message is sent back. If the sender contract does not handle bounces correctly, funds can be lost in limbo
  • Message ordering: Because contracts communicate asynchronously across shards, the order of message delivery is not guaranteed. This can create race conditions
  • Storage fee drainage: Contracts that accumulate too much state data without paying storage fees can be frozen, locking user funds
  • Reentrancy (different from Ethereum): While traditional reentrancy is less of a concern due to the message model, new patterns of "callback reentrancy" via message chains exist
  • Unverified contracts: Many TON contracts are not open-source or audited. You cannot verify what the code does before interacting with it

How to Evaluate a TON DeFi Project

1
Check for audits

Has the project been audited by a reputable security firm? Look for audit reports on the project's documentation or GitHub. Major firms auditing TON projects include CertiK, Quantstamp, and Trail of Bits.

2
Verify open-source code

Is the smart contract code publicly available? Closed-source contracts are a red flag — you cannot verify what they do with your funds.

3
Research the team

Are the developers known and reputable? Anonymous teams are higher risk. Check their track record on previous projects.

4
Check TVL and age

How much total value is locked (TVL) in the protocol? How long has it been running? Newer protocols with low TVL are higher risk. Established protocols with significant TVL have more to lose from exploits.

5
Be skeptical of unrealistic yields

If a protocol offers 1000% APY, ask where the yield comes from. Sustainable yields come from trading fees or lending interest. Unsustainable yields come from token emissions (printing new tokens), which dilute value over time.

Common DeFi Scams on TON

  • Fake DEX frontends: Phishing sites that look like STON.fi or DeDust but steal your wallet connection
  • Honeypot tokens: Tokens you can buy but cannot sell — the sell function is disabled in the contract
  • Rug pulls: Projects that collect liquidity then drain the pool and disappear
  • Flash loan manipulation: Attackers exploit price oracles to drain lending protocols
  • Approval exploits: Malicious contracts that request unlimited token approval, then drain your wallet later

Summary

  • TON DeFi includes DEXs, liquidity pools, lending, and yield farming
  • Impermanent loss is the biggest risk for liquidity providers
  • TON's asynchronous contracts create unique vulnerability classes
  • Always check for audits, open-source code, and team reputation before using a protocol
  • Unrealistic yields are the primary red flag for scams
  • Start small, test with amounts you can afford to lose, and never invest more than you can lose
🎉
You can now navigate TON DeFi safely!

With this knowledge, you can evaluate projects critically and protect yourself from the most common risks.

Related Tutorials