Address tracking

Address tracking is a trigger mechanism that monitors a specific on-chain address, such as a smart contract or wallet address, and activates your workflow whenever activity involving that address is detected. Unlike event-based triggers that require you to specify exact event names, address tracking acts as a broad listener that fires on any on-chain interaction with the tracked address. When you enable address tracking, the Kwala engine monitors activity based on two key configuration fields:

Which address? -TriggerSourceContract (one-time) or RecurringSourceContract (recurring)
On which network? - TriggerChainID or RecurringChainID

What activities does address tracking detect?

Address tracking detects several types of on-chain activity. Transactions involving the address Address tracking captures any transaction where the tracked address is the receiver (to == trackedAddress), including contract calls and direct transfers. It also detects transactions where the tracked address is the sender (from == trackedAddress), capturing all outbound activity. Logs and events emitted by the contract The tracker listens for any event emitted by the tracked contract, even without filtering by a specific event name. This essentially acts as a catch-all for any event emitted by this contract.” State and balance changes Although less common, address tracking can also detect native token balance changes and token balance changes for the address.

Think of address tracking as a broad catch-all trigger: Whenever anything happens on-chain involving this address, activate the workflow.

Address tracking vs event triggers

Kwala supports monitoring on-chain activity using event triggers and address tracking. Event triggers are more precise as they listen for specific contract events, while address tracking provides broader coverage by capturing all activity involving an address. The following table highlights the key differences:

Aspect	Event Trigger	Address Tracking
Specificity	Requires `EventName` and optional ABI	No `EventName` needed
Scope	Specific event only	Any activity for the address
Use case	Known, well-defined events	Unknown events, general monitoring
Configuration	`TriggerEventName: Transfer(...)`	`ExecuteAfter: address_tracking`

Choose event triggers when you know the exact event to monitor, and address tracking when you need to capture all interactions with an address regardless of event type. Address tracking can be combined with different ExecuteAfter and RepeatEvery values to create various monitoring patterns. The most common address tracking pattern is triggering a workflow once when address activity is detected then continue monitoring subsequent activities.

ExecuteAfter: address_tracking
RepeatEvery: address_tracking

The first match fires a one-time run using the Trigger fields, while subsequent activity continues to trigger runs using the Recurring fields.

Address tracking runtime payload

When address tracking triggers your workflow, it passes a transaction receipt as input. This receipt contains details about the transaction that activated the trigger. A receipt contains the following key fields:

Field	Description
`from`	Transaction sender (who initiated or signed the transaction)
`to`	Contract/EOA being called or sent to (empty for contract deployments)
`contractAddress`	Set only for contract deployments; otherwise `null`
`transactionHash`	Unique identifier for the transaction
`chainId`	Network identifier
`blockNumber`	Block where the transaction was included
`logs`	Array of events emitted during the transaction

Example receipt payload The following example shows the standard receipt format returned by address tracking:

{
  "to": "",
  "from": "0x37D041281eBf650330336526297b343bC455F68C",
  "contractAddress": "0xAbCdEf0123456789aBCdef0123456789abCDef01",
  "transactionIndex": 2,
  "gasUsed": { "_hex": "0x2dc6c0", "_isBigNumber": true },
  "logsBloom": "0x...",
  "blockHash": "0xdef...",
  "transactionHash": "0x9a2f...c41e",
  "logs": [],
  "blockNumber": 31945000,
  "confirmations": 50,
  "cumulativeGasUsed": { "_hex": "0x2dc6c0", "_isBigNumber": true },
  "effectiveGasPrice": { "_hex": "0x06fc23ac3f", "_isBigNumber": true },
  "status": 1,
  "type": 2,
  "byzantium": true,
  "chainId": "0x13882"
}

When to is empty and contractAddress is set, this indicates a contract deployment transaction.

Commonly used fields The following fields are commonly forwarded to notification or automation endpoints:

transactionHash: Verify the activity on a block explorer
chainId: Identify the network
blockNumber: Reference the specific block
from or to: Identify the parties involved in the transaction
logs[]: Decode emitted events for advanced use cases

Using receipt data in dynamic actions

Dynamic actions can extract values from the runtime receipt using the re.event(index) function, which maps to specific fields in Kwala’s runtime payload. While you can reference individual fields by index, the most reliable approach is to send the entire receipt to your backend for parsing.

Actions:
  - Name: NotifyDynamic
    Type: post
    APIEndpoint: https://your-api.example.com/webhook
    APIPayload:
      tracker: "Address Tracking"
      mode: "dynamic"
      rawReceipt: re.event(0)
    RetriesUntilSuccess: 5

The re.event(0) function returns the full transaction receipt. For maximum flexibility, send the raw receipt to your backend and parse it there.

Your receiving backend can then extract transactionHash, chainId, blockNumber, from, to, and logs, then enrich notifications with explorer links and decoded details.

Parse receipt data

The receipt payload contains fields like from, to, logs, chainId, and topics that you can use in your downstream processing. For reliable parsing, send the raw receipt JSON to a smart contract or Web2 backend rather than extracting fields directly in the workflow. Recommended parsing format (Go) The following Go structs can be used to parse the receipt JSON in your Web2 service:

type BigNumber struct {
    Hex         string `json:"_hex"`
    IsBigNumber bool   `json:"_isBigNumber"`
}

type Receipt struct {
    To                string     `json:"to"`
    From              string     `json:"from"`
    ContractAddress   *string    `json:"contractAddress"`
    TransactionIndex  uint       `json:"transactionIndex"`
    GasUsed           BigNumber  `json:"gasUsed"`
    LogsBloom         string     `json:"logsBloom"`
    BlockHash         string     `json:"blockHash"`
    TransactionHash   string     `json:"transactionHash"`
    Logs              []Log      `json:"logs"`
    BlockNumber       uint64     `json:"blockNumber"`
    Confirmations     uint64     `json:"confirmations"`
    CumulativeGasUsed BigNumber  `json:"cumulativeGasUsed"`
    EffectiveGasPrice BigNumber  `json:"effectiveGasPrice"`
    Status            uint       `json:"status"`
    Type              uint       `json:"type"`
    Byzantium         bool       `json:"byzantium"`
    ChainID           string     `json:"chainId"`
}

type Log struct {
    TransactionIndex uint     `json:"transactionIndex"`
    BlockNumber      uint64   `json:"blockNumber"`
    TransactionHash  string   `json:"transactionHash"`
    Address          string   `json:"address"`
    Topics           []string `json:"topics"`
    Data             string   `json:"data"`
    LogIndex         uint     `json:"logIndex"`
    BlockHash        string   `json:"blockHash"`
}

Common field usage The following parsed fields can be used for downstream processing:

receipt.TransactionHash — Build explorer links and verify activity
receipt.ChainID — Identify the network
receipt.ContractAddress — Identify the contract involved (if present)
receipt.Logs — Inspect emitted events
- log.Address — Determine which contract emitted the log
- log.Topics[] — Access event signatures and indexed parameters
- log.Data — Access non-indexed event data

Example receipts

EOA to contract transfer The following example shows a receipt when a user wallet transfers ERC-20 tokens to a staking contract

{
  "to": "0x53b6462b067419e92c31abff8ea849c06cea6d40",
  "from": "0x18fcd17b107348bd54c05da39cf53621b892bcac",
  "contractAddress": null,
  "transactionIndex": 0,
  "gasUsed": { "_hex": "0x5208", "_isBigNumber": true },
  "blockHash": "0xb924bea3d8711878cf19a6f47970640727c801e16a866d2d388dbac20121f817",
  "transactionHash": "0xe96777ab7dad67479d9f6b64305266a4ca61833e01c5a50d4d49e15a374b0be2",
  "logs": [
    {
      "transactionIndex": 0,
      "blockNumber": 31939718,
      "transactionHash": "0xe96777ab7dad67479d9f6b64305266a4ca61833e01c5a50d4d49e15a374b0be2",
      "address": "0x35aE84d69fbb55Dac834d956a042758F02fD3CFc",
      "topics": [
        "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
        "0x00000000000000000000000018fcd17b107348bd54c05da39cf53621b892bcac",
        "0x00000000000000000000000053b6462b067419e92c31abff8ea849c06cea6d40"
      ],
      "data": "0x0000000000000000000000000000000000000000000000000de0b6b3a7640000",
      "logIndex": 0,
      "blockHash": "0xb924bea3d8711878cf19a6f47970640727c801e16a866d2d388dbac20121f817"
    }
  ],
  "blockNumber": 31939718,
  "confirmations": 120,
  "status": 1,
  "type": 2,
  "byzantium": true,
  "chainId": "0x13882"
}

In this receipt, the contractAddress is null or 0x000... because this is not a contract deployment. The logs capture a standard ERC-20 Transfer event:

topics[0] = ERC-20 Transfer event signature
topics[1] = from address (EOA)
topics[2] = to address (contract)
data = transfer amount (here 0x0de0b6b3a7640000 = 1e18, or 1 token with 18 decimals)

DEX swap with multiple logs The following example shows a receipt from a DEX swap where multiple contracts emit logs: DEX swap with multiple logs In a DEX swap, multiple contracts emit logs during a single transaction. Token contracts emit Transfer events as assets move between addresses, while the pool contract emits a Swap event. The to field points to the DEX router contract, and the logs array captures all emitted events:

{
  "to": "0x1111111254eeb25477b68fb85ed929f73a960582",
  "from": "0x18fcd17b107348bd54c05da39cf53621b892bcac",
  "contractAddress": null,
  "transactionIndex": 5,
  "gasUsed": { "_hex": "0x01c9c380", "_isBigNumber": true },
  "blockHash": "0xabc...",
  "transactionHash": "0x7b1d0b6f6d2c9d0fb3c4aa9c0c1f8a2b3a0d9e5b7d3a1c8f2e1a9d8c7b6a5f4e",
  "logs": [
    {
      "blockNumber": 31940111,
      "transactionHash": "0x7b1d0b6f6d2c9d0fb3c4aa9c0c1f8a2b3a0d9e5b7d3a1c8f2e1a9d8c7b6a5f4e",
      "address": "0x35aE84d69fbb55Dac834d956a042758F02fD3CFc",
      "topics": [
        "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
        "0x00000000000000000000000018fcd17b107348bd54c05da39cf53621b892bcac",
        "0x0000000000000000000000009b8a7c6d5e4f32100123456789abcdeffedcba98"
      ],
      "data": "0x0000000000000000000000000000000000000000000000000000000002faf080",
      "logIndex": 12
    },
    {
      "blockNumber": 31940111,
      "transactionHash": "0x7b1d0b6f6d2c9d0fb3c4aa9c0c1f8a2b3a0d9e5b7d3a1c8f2e1a9d8c7b6a5f4e",
      "address": "0x7cEb23fD6bC0adD59E62ac25578270cFf1b9f619",
      "topics": [
        "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
        "0x0000000000000000000000009b8a7c6d5e4f32100123456789abcdeffedcba98",
        "0x00000000000000000000000018fcd17b107348bd54c05da39cf53621b892bcac"
      ],
      "data": "0x0000000000000000000000000000000000000000000000000058d15e17628000",
      "logIndex": 13
    },
    {
      "blockNumber": 31940111,
      "transactionHash": "0x7b1d0b6f6d2c9d0fb3c4aa9c0c1f8a2b3a0d9e5b7d3a1c8f2e1a9d8c7b6a5f4e",
      "address": "0x9b8a7c6d5e4f32100123456789abcdeffedcba98",
      "topics": [
        "0xd78ad95fa46c994b6551d0da85fc275fe613ce37657fb8d5e3d130840159d822",
        "0x0000000000000000000000001111111254eeb25477b68fb85ed929f73a960582",
        "0x00000000000000000000000018fcd17b107348bd54c05da39cf53621b892bcac"
      ],
      "data": "0x...",
      "logIndex": 14
    }
  ],
  "blockNumber": 31940111,
  "confirmations": 120,
  "status": 1,
  "type": 2,
  "byzantium": true,
  "chainId": "0x13882"
}

The three logs trace the swap lifecycle: the user sends tokens to the pool (Log #1), receives different tokens back (Log #2), and the pool records the swap (Log #3):

Log #1: Transfer — User → Pool, amount = 0x2faf080 (50 × 10⁶)
Log #2: Transfer — Pool → User, amount = 0x58d15e17628000 (~0.025 × 10¹⁸)
Log #3: Swap — Emitted by the pool contract

Many RPCs return contractAddress as null, "", or 0x000...000 for non-deployment transactions where no contract is created.

Example workflows

The following example shows a complete address tracking workflow that demonstrates both static and dynamic notification patterns. This workflow monitors an address on Polygon Amoy (chain ID 80002) and fires two actions whenever activity is detected:

NotifyStatic: Sends the same fixed message every time, useful for simple alerts
NotifyDynamic: Sends transaction details extracted from the runtime payload using re.event(index), where the index maps to specific fields from the activity event

Name: address_tracking_flow

Trigger:
  # One-time address tracking source
  TriggerSourceContract: 0x18fcd17b107348bd54c05da39cf53621b892bcac
  TriggerChainID: 80002
  TriggerEventName: NA
  TriggerEventFilter: NA
  TriggerSourceContractABI: NA

  # Recurring address tracking source
  RecurringSourceContract: 0x18fcd17b107348bd54c05da39cf53621b892bcac
  RecurringChainID: 80002
  RecurringEventName: NA
  RecurringEventFilter: NA
  RecurringSourceContractABI: NA

  # Address tracking configuration
  ExecuteAfter: address_tracking
  RepeatEvery: address_tracking
  ExpiresIn: 1881016603

Actions:
  # Static action (same payload every time)
  - Name: NotifyStatic
    Type: post
    APIEndpoint: https://your-api.example.com/webhook
    APIPayload:
      tracker: "Address Tracking"
      mode: "static"
      message: "Address tracking triggered"
    RetriesUntilSuccess: 5

  # Dynamic action (payload includes receipt data)
  - Name: NotifyDynamic
    Type: post
    APIEndpoint: https://your-api.example.com/webhook
    APIPayload:
      tracker: "Address Tracking"
      mode: "dynamic"
      rawReceipt: re.event(0)
    RetriesUntilSuccess: 5

Execution:
  Mode: parallel

Testing address tracking

To test your address tracking workflow:

Deploy or pick a contract address

Use an existing contract address on chain 80002 (Polygon Amoy) or deploy a new one. The example workflow uses 0x18fcd17b107348bd54c05da39cf53621b892bcac.

Trigger on-chain activity

Initiate any call or transaction involving that address. This could be a token transfer, a contract function call, or any other on-chain interaction.

Confirm your notification endpoint receives the payloads

Your webhook should receive two payloads:

NotifyStatic: A fixed message ("Address tracking triggered") sent every time
NotifyDynamic: Transaction details like txHash and blockNumber populated from re.event(index), where the index corresponds to the position of the value in the activity event data

Verify against a block explorer

Cross-reference the txHash and blockNumber values from the dynamic payload against PolygonScan Amoy or your target chain’s explorer to confirm accuracy.

Real-world use cases

The following example demonstrate how address tracking solves common blockchain monitoring challenges where you need to capture activities involving an address, not just specific events.

Whale wallet tracking

Trading desks and analytics platforms monitor high-value wallets (“whales”) to detect market-moving activity before it impacts prices. The challenge: Whale wallets interact with dozens of protocols including DEXs, lending platforms, bridges, and more. Each protocol has different event signatures, and new DeFi protocols launch constantly. Maintaining event triggers for every possible interaction is unsustainable. By the time you’ve configured triggers for one protocol, others have launched. The solution: Address tracking monitors the whale’s wallet address and fires on any outbound or inbound activity. The goal is to track a whale wallet or contract and trigger your analytics or strategy pipeline on movement. You don’t need the event name; you just need to know “whale moved.” To do this, set ExecuteAfter: address_tracking and RepeatEvery: address_tracking to continuously monitor whale activity. Actions:

Dynamic (using re.event(0)): POST the dynamic event to your strategy service, which decides whether to buy, sell, or do nothing based on the transaction context

This gives you coverage across all protocols without maintaining event lists. Your trading desk receives real-time signals when whale wallets move, and your analysis pipeline gets the full transaction context to decode interactions and execute trading decisions.

Treasury wallet monitoring

Address tracking is ideal for treasury wallets where funds can move through various methods: direct transfers, multisig executions, delegate calls, or contract interactions. Instead of configuring triggers for each scenario, you can use address tracking to monitor the treasury address directly and receive alerts whenever any on-chain activity occurs.

Next steps

Triggers

Learn about all trigger types

Kwala Functions

Create custom on-chain logic

Actions

Configure workflow actions

YAML Basics

Master Kwala’s YAML syntax

Overview

Getting started

Use the Workflow Builder

Use cases

Concepts

Reference

Resources

What activities does address tracking detect?

Address tracking vs event triggers

Address tracking runtime payload

Using receipt data in dynamic actions

Parse receipt data

Example receipts

Example workflows

Testing address tracking

Real-world use cases

Whale wallet tracking

Treasury wallet monitoring

Next steps

Triggers

Kwala Functions

Actions

YAML Basics

Overview

Getting started

Use the Workflow Builder

Use cases

Concepts

Reference

Resources

​What activities does address tracking detect?

​Address tracking vs event triggers

​Address tracking runtime payload

​Using receipt data in dynamic actions

​Parse receipt data

​Example receipts

​Example workflows

​Testing address tracking

​Real-world use cases

​Whale wallet tracking

​Treasury wallet monitoring

​Next steps

Triggers

Kwala Functions

Actions

YAML Basics

What activities does address tracking detect?

Address tracking vs event triggers

Address tracking runtime payload

Using receipt data in dynamic actions

Parse receipt data

Example receipts

Example workflows

Testing address tracking

Real-world use cases

Whale wallet tracking

Treasury wallet monitoring

Next steps