Ponder is an open-source framework for blockchain application backends.
Visit ponder.sh for documentation, guides, and the API reference.
Join Ponder's telegram chat for support, feedback, and general chatter.
✅ Local development server with hot reloading
✅ create-ponder
CLI tool to get started from an Etherscan link or Graph Protocol subgraph
✅ End-to-end type safety using viem and ABIType
✅ Autogenerated GraphQL API
✅ Easy to deploy anywhere using Node.js/Docker
✅ Supports all Ethereum-based blockchains, including test nodes like Anvil
✅ Index events from multiple chains in the same app
✅ Reconciles chain reorganization
✅ Factory contracts
🏗️ Process transactions calls (in addition to logs)
🏗️ Run effects (e.g. send an API request) in indexing code
You will be asked for a project name, and if you are using a template (recommended). Then, the CLI will create a project directory, install dependencies, and initialize a git repository.
npm init ponder@latest
# or
pnpm create ponder
# or
yarn create ponder
Just like Next.js and Vite, Ponder has a development server that automatically reloads when you save changes in any project file. It also prints console.log
statements and errors encountered while running your code. First, cd
into your project directory, then start the server.
npm run dev
# or
pnpm dev
# or
yarn dev
Ponder fetches event logs for the contracts added to ponder.config.ts
, and passes those events to the indexing functions you write.
// ponder.config.ts
import { createConfig } from "@ponder/core";
import { http } from "viem";
import { BaseRegistrarAbi } from "./abis/BaseRegistrar";
export default createConfig({
networks: {
mainnet: {
chainId: 1,
transport: http("https://eth-mainnet.g.alchemy.com/v2/...")
},
},
contracts: {
BaseRegistrar: {
abi: BaseRegistrarAbi,
network: "mainnet",
address: "0x57f1887a8BF19b14fC0dF6Fd9B2acc9Af147eA85",
startBlock: 9380410,
},
},
});
The ponder.schema.ts
file contains the database schema, and defines the shape data that the GraphQL API serves.
// ponder.schema.ts
import { createSchema } from "@ponder/core";
export default createSchema((p) => ({
EnsName: p.createTable({
id: p.string(),
name: p.string(),
owner: p.string(),
registeredAt: p.int(),
}),
}));
Files in the src/
directory contain indexing functions, which are TypeScript functions that process a contract event. The purpose of these functions is to insert data into the entity store.
// src/BaseRegistrar.ts
import { ponder } from "@/generated";
ponder.on("BaseRegistrar:NameRegistered", async ({ event, context }) => {
const { EnsName } = context.entities;
const { name, owner } = event.params;
await EnsName.create({
id: `${name}-${owner}`,
data: {
name: name,
owner: owner,
registeredAt: event.block.timestamp,
},
});
});
See the create & update records docs for a detailed guide on writing indexing functions.
Ponder automatically generates a frontend-ready GraphQL API based on your ponder.schema.ts
file. The API serves data that you inserted in your indexing functions.
{
ensNames(limit: 2) {
items {
name
owner
registeredAt
}
}
}
{
"ensNames": {
"items": [
{
"name": "vitalik.eth",
"owner": "0x0904Dac3347eA47d208F3Fd67402D039a3b99859",
"registeredAt": 1580345271
},
{
"name": "joe.eth",
"owner": "0x6109DD117AA5486605FC85e040ab00163a75c662",
"registeredAt": 1580754710
}
]
}
}
That's it! Visit ponder.sh for documentation, guides for deploying to production, and the API reference.
If you're interested in contributing to Ponder, please read the contribution guide.
@ponder/core
@ponder/utils
create-ponder
eslint-config-ponder
Ponder is MIT-licensed open-source software.