> ## Documentation Index
> Fetch the complete documentation index at: https://goldrush.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Decode Uniswap V3 Swaps

> Capture every Uniswap V3 swap event on Base Mainnet as structured rows in your Postgres database using GoldRush Pipeline API.

## Use Case

Uniswap V3 is one of the highest-volume DEX protocols on Base. If you are building trading analytics, monitoring liquidity, or tracking volume trends, you need a reliable stream of decoded swap events landing in a queryable database.

This guide walks you through configuring a pipeline that:

* Subscribes to decoded log events on Base Mainnet
* Filters for the Uniswap V3 `Swap` event using ABI decoding
* Writes structured swap rows into a Postgres table

## Prerequisites

* A GoldRush API key with Pipeline API access
* A Postgres database reachable from the internet (or via VPN peering)
* The Uniswap V3 Pool ABI (the `Swap` event signature)

## Pipeline Configuration

The following YAML is generated by the GoldRush Platform when you complete the setup steps below.

```yaml theme={null}
project: "uniswap-analytics"
topic: "base.mainnet.ref.block.logs"

destination:
  type: "postgres"
  url: "postgresql://your-host:5432/analytics"
  user: "${PG_USER}"
  password: "${PG_PASSWORD}"
  batch_size: 1000

abi:
  path: "uniswap-v3-pool.json"
  contract_addresses:
    - "0x68b3465833fb72a70ecdf485e0e4c7bd8665fc45"
  unmatched: "skip"

transforms:
  base_evt_swap: >
    SELECT block_height, block_signed_at, tx_hash, contract_address,
           sender, recipient, amount0, amount1, sqrt_price_x96, liquidity, tick
    FROM base_evt_swap
```

### Key Configuration Details

| Field                      | Purpose                                                                                             |
| -------------------------- | --------------------------------------------------------------------------------------------------- |
| `topic`                    | `base.mainnet.ref.block.logs` delivers all decoded log events on Base Mainnet.                      |
| `abi.path`                 | Points to the Uniswap V3 Pool ABI. The platform provides common ABIs; you can also upload your own. |
| `abi.contract_addresses`   | Restricts decoding to the specified contract. Add more addresses to cover additional pools.         |
| `abi.unmatched`            | Set to `skip` so that log events not matching the ABI are silently dropped.                         |
| `transforms.base_evt_swap` | A SQL transform that selects specific columns from the decoded `evt_swap` table.                    |
| `destination.batch_size`   | Rows are flushed to Postgres in batches of 1,000 for throughput.                                    |

### ABI Snippet

The pipeline uses the `Swap` event from the Uniswap V3 Pool contract:

```json theme={null}
{
  "anonymous": false,
  "inputs": [
    { "indexed": true, "name": "sender", "type": "address" },
    { "indexed": true, "name": "recipient", "type": "address" },
    { "indexed": false, "name": "amount0", "type": "int256" },
    { "indexed": false, "name": "amount1", "type": "int256" },
    { "indexed": false, "name": "sqrtPriceX96", "type": "uint160" },
    { "indexed": false, "name": "liquidity", "type": "uint128" },
    { "indexed": false, "name": "tick", "type": "int24" }
  ],
  "name": "Swap",
  "type": "event"
}
```

## Deploy via the GoldRush Platform

<Steps>
  <Step title="Create a new pipeline">
    Log in to the [GoldRush Platform](https://goldrush.dev/platform/) and navigate to **Manage Pipeline API** in the left sidebar. Click **Create Pipeline**.
  </Step>

  <Step title="Configure the Postgres destination">
    Select **Postgres** as the destination type. Enter your JDBC connection URL, and use environment variable references (`${PG_USER}`, `${PG_PASSWORD}`) for credentials. Set **Batch size** to `1000`.
  </Step>

  <Step title="Select source topic">
    Choose **Base Mainnet** as the network and **Block Logs** (`base.mainnet.ref.block.logs`) as the data topic.
  </Step>

  <Step title="Configure ABI decoding">
    In the **ABI Decoding** section, select the built-in **Uniswap V3 Pool** ABI or upload your own JSON ABI file. Enter the contract address `0x68b3465833fb72a70ecdf485e0e4c7bd8665fc45`. Set **Unmatched events** to **Skip**.
  </Step>

  <Step title="Add a SQL transform">
    In the **Transforms** section, add a transform for the `base_evt_swap` output table. Paste the SQL SELECT statement from the configuration above to project only the columns you need.
  </Step>

  <Step title="Deploy">
    Review the generated YAML configuration, then click **Create**. The pipeline will begin consuming events within a few seconds.
  </Step>
</Steps>

## Verify the Pipeline

Once the pipeline is running, connect to your Postgres database and confirm that data is arriving:

```sql theme={null}
-- Check row count
SELECT COUNT(*) FROM evt_swap;

-- View the most recent swaps
SELECT block_height, tx_hash, sender, recipient,
       amount0, amount1, tick
FROM evt_swap
ORDER BY block_height DESC
LIMIT 10;

-- Aggregate swap volume over the last hour
SELECT DATE_TRUNC('minute', block_signed_at) AS minute,
       COUNT(*) AS swap_count,
       SUM(ABS(amount0)) AS total_amount0
FROM evt_swap
WHERE block_signed_at > NOW() - INTERVAL '1 hour'
GROUP BY 1
ORDER BY 1 DESC;
```

## Tips

<AccordionGroup>
  <Accordion title="Scaling for production">
    Increase `batch_size` to 5,000 or higher if your Postgres instance can handle larger write batches. This reduces the number of round trips and improves throughput during high-volume periods.
  </Accordion>

  <Accordion title="Monitoring multiple pools">
    Add additional contract addresses to the `abi.contract_addresses` list to capture swaps across multiple Uniswap V3 pools in a single pipeline.
  </Accordion>

  <Accordion title="Indexing for query performance">
    Create indexes on `block_height`, `tx_hash`, and `contract_address` in your Postgres table to speed up common analytical queries.
  </Accordion>

  <Accordion title="Handling schema changes">
    If the ABI changes (for example, a new version of the pool contract), create a new pipeline with the updated ABI. The platform does not modify existing table schemas automatically.
  </Accordion>
</AccordionGroup>