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Copy-paste these configs into the Beam pipeline builder or use them with the API.

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Filter logs by contract address

Monitor USDC transfer logs on Polygon by filtering to the USDC contract address.
USDC log filter pipeline in Beam UI
{
  "name": "USDC Transfer Monitor",
  "description": "Monitor USDC transfers on Polygon",
  "source": {
    "chain": "polygon",
    "entity": "log"
  },
  "transforms": [
    {
      "type": "redis_set_filter",
      "set_values": [
        "0x3c499c542cef5e3811e1192ce70d8cc03d5c3359"
      ],
      "filter_expr": "root = this.address"
    }
  ],
  "sinks": [
    {
      "type": "kafka",
      "name": "usdc-logs"
    }
  ]
}
Uses filter_expr: "root = this.address" to match the address field (the contract that emitted the log) against the USDC contract.

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Filter + JavaScript transform

Filter for DEX swap events by topic signature, then enrich with a JavaScript transform.
DEX trade parser pipeline in Beam UI
{
  "name": "DEX Trade Parser",
  "description": "Parse DEX swap events and extract trade details",
  "source": {
    "chain": "polygon",
    "entity": "log"
  },
  "transforms": [
    {
      "type": "redis_set_filter",
      "set_values": [
        "0xd78ad95fa46c994b6551d0da85fc275fe613ce37657fb8d5e3d130840159d822"
      ],
      "filter_expr": "root = this.topic0"
    },
    {
      "type": "v8",
      "script": "function transform(record) { record.parsed = true; return record; }"
    }
  ],
  "sinks": [
    {
      "type": "kafka",
      "name": "dex-trades"
    }
  ]
}
The set filter narrows to swap events using topic0 (the event signature hash). The v8 transform then enriches each matching record. Transforms are chained — data flows through the filter first, then the JavaScript.

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ERC-20 token transfers on Base

Track USDC token transfers on Base using the erc20_token_transfer entity instead of raw logs.
Base USDC token transfer pipeline in Beam UI
{
  "name": "Base Token Transfer Tracker",
  "description": "Monitor ERC-20 token transfers on Base",
  "source": {
    "chain": "base",
    "entity": "erc20_token_transfer"
  },
  "transforms": [
    {
      "type": "redis_set_filter",
      "set_values": [
        "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913"
      ],
      "filter_expr": "root = this.address"
    }
  ],
  "sinks": [
    {
      "type": "kafka",
      "name": "base-usdc-transfers"
    }
  ]
}
The erc20_token_transfer entity provides pre-parsed transfer data (from, to, amount) so you don’t need to decode raw logs yourself.

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Multiple contract addresses

Monitor USDC and USDT on Polygon in a single pipeline by providing multiple addresses in set_values.
Multi-token monitor pipeline in Beam UI
{
  "name": "Multi-Token Monitor",
  "description": "Monitor USDC and USDT on Polygon",
  "source": {
    "chain": "polygon",
    "entity": "log"
  },
  "transforms": [
    {
      "type": "redis_set_filter",
      "set_values": [
        "0x3c499c542cef5e3811e1192ce70d8cc03d5c3359",
        "0xc2132d05d31c914a87c6611c10748aeb04b58e8f"
      ],
      "filter_expr": "root = this.address"
    }
  ],
  "sinks": [
    {
      "type": "kafka",
      "name": "stablecoin-logs"
    }
  ]
}
All addresses in set_values are matched with OR logic — a record passes if its address matches any value in the set. You can include hundreds or thousands of addresses (100K+ supported for wallet set lookups).