Data Analyst Guide to Aptos: DeFi Swaps on Aptos Blockchain

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Introduction to DeFi Swaps on Aptos

Decentralized Finance (DeFi) is transforming traditional financial systems by enabling peer-to-peer asset exchanges without intermediaries. On Aptos, a high-performance blockchain, DeFi applications like asset trading, lending, and liquid staking derivatives are gaining traction. This guide focuses on analyzing swap transactions—where users exchange one asset for another—using Automated Market Makers (AMMs).

Key DeFi Applications on Aptos

  1. Asset Trading: Spot trading via AMMs or Central Limit Order Books (CLOBs)
  2. Lending Protocols: Decentralized borrowing/lending platforms
  3. Liquid Staking: Derivatives for staked assets

How DeFi Swaps Work on Aptos

Swaps on Aptos leverage AMM pools, where liquidity providers deposit assets to facilitate trades. Aptos supports two asset standards:

Identifying Swap Transactions

To analyze swaps, start by querying transactions from popular decentralized exchanges (DEXs) like Liquidswap:

SELECT *
FROM `bigquery-public-data.crypto_aptos_mainnet_us.transactions`
WHERE tx_type = 'user'
AND success
AND payload.entry_function_id_str = '0x9dd974aea0f927ead664b9e1c295e4215bd441a9fb4e53e5ea0bf22f356c8a2b::router::swap_exact_coin_for_coin_x1'
LIMIT 100

Pro Tip: Normalize addresses for consistent filtering using entry_function_id_str_normalized.

Analyzing Swap Transactions

Step 1: Extract Balance Changes

Track asset movements via fungible_asset_activities in Aptos' GraphQL API:

query get_balance {
  fungible_asset_activities(
    where: {transaction_version: {_eq: "2224014200"}}
  ) {
    event_index
    owner_address
    asset_type
    amount
  }
}

Step 2: Parse Events

Key events in a swap:

  1. Withdrawal: Asset leaves sender’s wallet
  2. Fee Accounting: Pool fees deducted (e.g., 0.1% on Liquidswap)
  3. Swap Execution: Core exchange logic
  4. Deposit: New asset arrives in sender’s wallet

Example: Event index 3 in Liquidswap logs pool reserves pre/post-swap for price impact analysis.

Step 3: Inspect On-Chain Changes

👉 Explore Aptos DeFi tools for deeper analytics.

Case Study: Swapping Fungible Assets via Cellana

Transaction: 2293960645
Swap: 13.387 APT → 100.12 USDt

Key Observations

  1. APT Conversion: Native APT is converted to Cellana’s FA-represented APT.
  2. Pool Mechanics: FA assets move through Thala v2 pools with clear event logging.
  3. Deterministic FA Addresses: Use sha3_256 to map Coin ↔ FA addresses.
def get_paired_fa(coin_type):
    apt_metadata_bytes = bytes.fromhex("000000000000000000000000000000000000000000000000000000000000000a")
    coin_type_bytes = coin_type.encode('utf-8')
    object_suffix = bytes.fromhex("fe")
    input_bytes = apt_metadata_bytes + coin_type_bytes + object_suffix
    return "0x" + hashlib.sha3_256(input_bytes).digest().hex()

Advanced Topics: Aggregators and Oracles

Panora Aggregator

Oracle Integrations

  1. Pyth: On-chain price feeds via table items.
  2. Switchboard: Decentralized price data in resources.
  3. Chainlink: SmartTables for real-time feeds.

FAQs

How do I find all assets owned by an address?

Query current_fungible_asset_balances for FA and scan CoinStore<% resources for legacy coins.

What’s the difference between Coin and FA standards?

Coins allow flexible storage (e.g., in resources), while FAs enforce stricter ownership rules with one FungibleStore per asset.

How are swap fees calculated?

Typically 0.1–0.3% of trade volume, logged in pool-specific fee events.

Conclusion

DeFi swaps on Aptos combine Move’s security with rich on-chain data. By parsing events, resources, and balance changes, analysts can track liquidity flows, fee structures, and price impacts. For further reading, explore Aptos’ fungible asset docs or dive into Ottersec’s FA guide.

👉 Start building on Aptos today with these actionable insights!