The Graph

The Graph

The Graph is a decentralized indexing protocol for querying blockchain data. Subgraphs define which smart contract events to index, how to transform them into entities, and expose them via a GraphQL API. The protocol supports Ethereum, Arbitrum, Optimism, Base, Polygon, Avalanche, BSC, Celo, Gnosis, and 40+ other networks.

What You Probably Got Wrong

• Hosted service is DEPRECATED -- do not use graph deploy --node https://api.thegraph.com/deploy/. Use Subgraph Studio exclusively. Hosted service endpoints stopped serving queries in Q2 2024. All documentation referencing --node https://api.thegraph.com/deploy/ is outdated.

• Mappings are AssemblyScript, NOT TypeScript -- despite .ts file extensions, subgraph mappings compile to WebAssembly via AssemblyScript. This means: no closures, no union types, no optional chaining (?.), no nullish coalescing (??), no Array.map/filter/reduce, no JSON.parse, no async/await, no try/catch. If you write standard TypeScript, the build will fail with cryptic errors.

• graph-ts types are NOT standard TS types -- BigInt, BigDecimal, Bytes, Address, and ethereum.Event come from @graphprotocol/graph-ts. They are NOT bigint, number, or Uint8Array. You must use BigInt.fromI32(), BigDecimal.fromString(), and Address.fromString() constructors. Arithmetic uses method calls: a.plus(b), a.minus(b), a.times(b), a.div(b).

• graph codegen must run before build -- entities and contract bindings are auto-generated from schema.graphql and ABIs. If you skip codegen, imports like import { Transfer } from '../generated/ERC20/ERC20' will fail. Always run graph codegen after ANY change to schema or ABIs.

• Entity IDs must be Bytes or String, not numeric -- the @entity directive requires an id field of type ID! which maps to Bytes or String in AssemblyScript. Using BigInt or Int as entity ID causes schema validation failure.

• store.get returns nullable -- Entity.load(id) returns Entity | null. You must null-check before accessing fields. AssemblyScript does not have optional chaining, so you need explicit if (entity != null) blocks.

• Subgraph Studio requires authentication per machine -- graph auth --studio <deploy-key> stores the key in ~/.graph. This is per-machine, not per-project. CI/CD must re-auth on each run.

Core Packages

npm install --save-dev @graphprotocol/graph-cli @graphprotocol/graph-ts

Subgraph Development Lifecycle

graph init --> graph codegen --> graph build --> graph deploy

1. Initialize a Subgraph

# Interactive init from a deployed contract
graph init --studio my-subgraph

# Non-interactive: specify all options
graph init --studio my-subgraph \
  --protocol ethereum \
  --network mainnet \
  --contract-name MyContract \
  --contract-address 0x1234567890abcdef1234567890abcdef12345678 \
  --abi ./abis/MyContract.json \
  --start-block 18000000

This generates:

• subgraph.yaml -- manifest
• schema.graphql -- entity definitions
• src/my-contract.ts -- mapping stubs (AssemblyScript)
• abis/MyContract.json -- contract ABI
• package.json with graph-cli and graph-ts

2. Define the Schema (schema.graphql)

Entities map to database tables. Each entity needs an id: ID! field.

type Token @entity {
  id: Bytes!
  name: String!
  symbol: String!
  decimals: Int!
  totalSupply: BigInt!
  holders: [TokenHolder!]! @derivedFrom(field: "token")
}

type TokenHolder @entity {
  id: Bytes!
  token: Token!
  address: Bytes!
  balance: BigInt!
  lastTransferBlock: BigInt!
  lastTransferTimestamp: BigInt!
}

type Transfer @entity(immutable: true) {
  id: Bytes!
  from: Bytes!
  to: Bytes!
  value: BigInt!
  token: Token!
  blockNumber: BigInt!
  blockTimestamp: BigInt!
  transactionHash: Bytes!
}

Schema rules:

• @entity marks a type as a stored entity
• @entity(immutable: true) for append-only entities (events) -- improves indexing speed significantly
• @derivedFrom(field: "token") creates a virtual reverse lookup without storing data
• Supported scalar types: ID, Bytes, String, Boolean, Int (i32), BigInt, BigDecimal
• Bytes! is preferred over String! for IDs derived from addresses or hashes -- it avoids hex encoding overhead

3. Write the Manifest (subgraph.yaml)

specVersion: 1.2.0
indexerHints:
  prune: auto
schema:
  file: ./schema.graphql
dataSources:
  - kind: ethereum
    name: ERC20
    network: mainnet
    source:
      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48"
      abi: ERC20
      startBlock: 6082465
    mapping:
      kind: ethereum/events
      apiVersion: 0.0.9
      language: wasm/assemblyscript
      entities:
        - Token
        - TokenHolder
        - Transfer
      abis:
        - name: ERC20
          file: ./abis/ERC20.json
      eventHandlers:
        - event: Transfer(indexed address,indexed address,uint256)
          handler: handleTransfer
        - event: Approval(indexed address,indexed address,uint256)
          handler: handleApproval
      file: ./src/mapping.ts

Manifest rules:

• specVersion: 1.2.0 is the current spec
• startBlock should be the contract deployment block -- indexing from block 0 wastes hours
• Event signatures must match the ABI exactly, including indexed keywords
• indexerHints.prune: auto enables automatic pruning of historical entity versions to reduce disk usage
• apiVersion: 0.0.9 is the current mapping API version

4. Write AssemblyScript Mappings

// src/mapping.ts -- this is AssemblyScript, NOT TypeScript
import { Transfer as TransferEvent } from "../generated/ERC20/ERC20";
import { Token, TokenHolder, Transfer } from "../generated/schema";
import { BigInt, Bytes, Address } from "@graphprotocol/graph-ts";

// Zero address constant -- reused across handlers
const ZERO_ADDRESS = Address.fromString(
  "0x0000000000000000000000000000000000000000"
);

export function handleTransfer(event: TransferEvent): void {
  // Create immutable Transfer entity (append-only, never updated)
  let transfer = new Transfer(event.transaction.hash.concatI32(event.logIndex.toI32()));
  transfer.from = event.params.from;
  transfer.to = event.params.to;
  transfer.value = event.params.value;
  transfer.blockNumber = event.block.number;
  transfer.blockTimestamp = event.block.timestamp;
  transfer.transactionHash = event.transaction.hash;

  // Load or create Token entity
  let token = Token.load(event.address);
  if (token == null) {
    token = new Token(event.address);
    token.name = "";
    token.symbol = "";
    token.decimals = 0;
    token.totalSupply = BigInt.fromI32(0);
  }

  transfer.token = token.id;
  transfer.save();
  token.save();

  // Update sender balance (skip mint events where from == zero address)
  if (event.params.from != ZERO_ADDRESS) {
    let senderId = event.address.concat(event.params.from);
    let sender = TokenHolder.load(senderId);
    if (sender == null) {
      sender = new TokenHolder(senderId);
      sender.token = token.id;
      sender.address = event.params.from;
      sender.balance = BigInt.fromI32(0);
    }
    sender.balance = sender.balance.minus(event.params.value);
    sender.lastTransferBlock = event.block.number;
    sender.lastTransferTimestamp = event.block.timestamp;
    sender.save();
  }

  // Update receiver balance (skip burn events where to == zero address)
  if (event.params.to != ZERO_ADDRESS) {
    let receiverId = event.address.concat(event.params.to);
    let receiver = TokenHolder.load(receiverId);
    if (receiver == null) {
      receiver = new TokenHolder(receiverId);
      receiver.token = token.id;
      receiver.address = event.params.to;
      receiver.balance = BigInt.fromI32(0);
    }
    receiver.balance = receiver.balance.plus(event.params.value);
    receiver.lastTransferBlock = event.block.number;
    receiver.lastTransferTimestamp = event.block.timestamp;
    receiver.save();
  }
}

5. Codegen and Build

# Generate types from schema.graphql and ABIs
graph codegen

# Compile AssemblyScript to WebAssembly
graph build

Common build errors:

• ERROR TS2322: Type 'X | null' is not assignable to type 'X' -- null-check before use
• ERROR TS2304: Cannot find name 'Transfer' -- run graph codegen first
• WARNING: using deprecated apiVersion -- update apiVersion in subgraph.yaml

6. Deploy to Subgraph Studio

# Authenticate (one-time per machine)
graph auth --studio <DEPLOY_KEY>

# Deploy with version label
graph deploy --studio my-subgraph --version-label v0.1.0

AssemblyScript Reference

Type System

BigInt Arithmetic

import { BigInt } from "@graphprotocol/graph-ts";

let a = BigInt.fromI32(100);
let b = BigInt.fromI32(50);

let sum = a.plus(b);          // 150
let diff = a.minus(b);        // 50
let product = a.times(b);     // 5000
let quotient = a.div(b);      // 2
let remainder = a.mod(b);     // 0
let power = a.pow(2);         // 10000

// Comparison
let isGreater = a.gt(b);      // true
let isEqual = a.equals(b);    // false
let isZero = a.isZero();      // false

BigDecimal Arithmetic

import { BigDecimal, BigInt } from "@graphprotocol/graph-ts";

let price = BigDecimal.fromString("1234.56");
let amount = BigDecimal.fromString("100");

let total = price.times(amount);       // 123456.00
let divided = price.div(amount);       // 12.3456

// Convert BigInt to BigDecimal for decimal math
let raw = BigInt.fromString("1000000000000000000"); // 1e18
let decimals = BigInt.fromI32(18);
let divisor = BigInt.fromI32(10).pow(decimals.toI32() as u8);
let normalized = raw.toBigDecimal().div(divisor.toBigDecimal()); // 1.0

Bytes Operations

import { Bytes, Address, ethereum } from "@graphprotocol/graph-ts";

// Create unique entity IDs from event data
let id = event.transaction.hash.concatI32(event.logIndex.toI32());

// Concatenate two Bytes values
let compositeId = event.address.concat(event.params.user);

// Convert Address to Bytes
let addr: Bytes = event.params.to;

// Hex string from Bytes
let hex = event.transaction.hash.toHexString();

Critical AssemblyScript Restrictions

These will cause build failures. No workaround exists:

// FORBIDDEN: closures / arrow functions as callbacks
// array.map(item => item.id)  <-- WILL NOT COMPILE

// FORBIDDEN: union types
// let x: string | null  <-- use nullable: string | null is OK only for class fields

// FORBIDDEN: optional chaining
// entity?.field  <-- WILL NOT COMPILE

// FORBIDDEN: nullish coalescing
// entity ?? defaultValue  <-- WILL NOT COMPILE

// FORBIDDEN: Array.map / filter / reduce
// Use a for loop instead:
let ids = new Array<string>();
for (let i = 0; i < items.length; i++) {
  ids.push(items[i].id.toHexString());
}

// FORBIDDEN: JSON.parse
// Use graph-ts json module if available, or decode manually

// FORBIDDEN: try/catch
// Errors in handlers cause the subgraph to fail and halt indexing

// FORBIDDEN: async/await
// All handlers are synchronous

Nullable Field Patterns

import { Token } from "../generated/schema";

// Loading an entity returns nullable
let token = Token.load(id);
if (token == null) {
  // Entity does not exist yet -- create it
  token = new Token(id);
  token.name = "Unknown";
  token.symbol = "???";
  token.decimals = 18;
  token.totalSupply = BigInt.fromI32(0);
}
// Safe to use token here -- guaranteed non-null
token.totalSupply = token.totalSupply.plus(amount);
token.save();

Handler Types

Event Handlers (most common)

Triggered when a specific event is emitted. Fastest and most reliable.

# subgraph.yaml
eventHandlers:
  - event: Transfer(indexed address,indexed address,uint256)
    handler: handleTransfer
  - event: Approval(indexed address,indexed address,uint256)
    handler: handleApproval

import { Transfer } from "../generated/ERC20/ERC20";

export function handleTransfer(event: Transfer): void {
  // event.params contains decoded event parameters
  let from = event.params.from;
  let to = event.params.to;
  let value = event.params.value;

  // event.block contains block metadata
  let blockNumber = event.block.number;
  let timestamp = event.block.timestamp;

  // event.transaction contains tx metadata
  let txHash = event.transaction.hash;
  let gasPrice = event.transaction.gasPrice;
}

Call Handlers

Triggered on function calls. Slower than event handlers. Not supported on all networks.

callHandlers:
  - function: transfer(address,uint256)
    handler: handleTransferCall

import { TransferCall } from "../generated/ERC20/ERC20";

export function handleTransferCall(call: TransferCall): void {
  let to = call.inputs._to;
  let value = call.inputs._value;
  let success = call.outputs.value0; // return value
}

Block Handlers

Triggered on every block (or filtered blocks). Use sparingly -- very expensive.

blockHandlers:
  - handler: handleBlock
    filter:
      kind: polling
      every: 100

import { ethereum } from "@graphprotocol/graph-ts";

export function handleBlock(block: ethereum.Block): void {
  let number = block.number;
  let timestamp = block.timestamp;
  let hash = block.hash;
}

GraphQL Query Patterns

Query endpoint: https://gateway.thegraph.com/api/{api-key}/subgraphs/id/{subgraph-id}

Basic Query

{
  tokens(first: 10, orderBy: totalSupply, orderDirection: desc) {
    id
    name
    symbol
    totalSupply
  }
}

Filtering with where

{
  transfers(
    where: {
      value_gt: "1000000000000000000"
      from: "0xabcdef1234567890abcdef1234567890abcdef12"
      blockTimestamp_gte: "1700000000"
    }
    first: 100
    orderBy: blockNumber
    orderDirection: desc
  ) {
    id
    from
    to
    value
    blockNumber
  }
}

Filter suffixes:

• field -- exact match
• field_not -- not equal
• field_gt / field_gte -- greater than / greater or equal
• field_lt / field_lte -- less than / less or equal
• field_in / field_not_in -- in array
• field_contains -- substring match (String only)
• field_starts_with / field_ends_with -- prefix/suffix match

Pagination

The Graph limits results to 1000 per query. For large datasets, paginate using first + skip or cursor-based pagination with id_gt.

# Skip-based (simple but slow for deep pages)
{
  transfers(first: 100, skip: 200, orderBy: blockNumber) {
    id
    value
  }
}

# Cursor-based (fast for any depth -- preferred)
{
  transfers(
    first: 1000
    where: { id_gt: "0xlast_seen_id" }
    orderBy: id
  ) {
    id
    from
    to
    value
  }
}

Pagination limit: skip maxes out at 5000. For datasets beyond 5000, use cursor-based pagination with id_gt.

Time-Travel Queries

Query entity state at a specific block number.

{
  tokens(block: { number: 18000000 }) {
    id
    name
    totalSupply
  }
}

Full-Text Search

Requires a @fulltext directive in the schema.

# schema.graphql
type _Schema_
  @fulltext(
    name: "tokenSearch"
    language: en
    algorithm: rank
    include: [{ entity: "Token", fields: [{ name: "name" }, { name: "symbol" }] }]
  )

{
  tokenSearch(text: "USDC") {
    id
    name
    symbol
  }
}

Data Source Templates (Dynamic Contracts)

For factory patterns where new contracts are deployed at runtime (e.g., Uniswap pairs, lending pools).

# subgraph.yaml
templates:
  - kind: ethereum
    name: Pair
    network: mainnet
    source:
      abi: Pair
    mapping:
      kind: ethereum/events
      apiVersion: 0.0.9
      language: wasm/assemblyscript
      entities:
        - Swap
      abis:
        - name: Pair
          file: ./abis/Pair.json
      eventHandlers:
        - event: Swap(indexed address,uint256,uint256,uint256,uint256,indexed address)
          handler: handleSwap
      file: ./src/pair.ts

// In factory handler -- dynamically create a new data source
import { Pair as PairTemplate } from "../generated/templates";

export function handlePairCreated(event: PairCreated): void {
  // Start indexing the new pair contract
  PairTemplate.create(event.params.pair);
}

Contract Reads (eth_call in Mappings)

Read on-chain state from within a mapping handler.

import { ERC20 } from "../generated/ERC20/ERC20";
import { Address } from "@graphprotocol/graph-ts";

export function handleTransfer(event: TransferEvent): void {
  // Bind to the contract at its address
  let contract = ERC20.bind(event.address);

  // try_ methods return ethereum.CallResult which has reverted flag
  let nameResult = contract.try_name();
  let symbolResult = contract.try_symbol();
  let decimalsResult = contract.try_decimals();

  let token = new Token(event.address);

  // Always use try_ to handle contracts that revert on view calls
  if (!nameResult.reverted) {
    token.name = nameResult.value;
  } else {
    token.name = "Unknown";
  }

  if (!symbolResult.reverted) {
    token.symbol = symbolResult.value;
  } else {
    token.symbol = "???";
  }

  if (!decimalsResult.reverted) {
    token.decimals = decimalsResult.value;
  } else {
    token.decimals = 18;
  }

  token.save();
}

Contract read rules:

• Always use try_ prefixed methods -- non-try methods abort the handler on revert
• Contract reads are eth_calls at the handler's block -- they see state at that block
• Reads are slow compared to event data -- minimize them
• Some contracts (proxies, non-standard ERC20s) revert on name() or symbol() -- always handle reverts

Indexing Performance Tips

Use Immutable Entities

Entities marked @entity(immutable: true) are append-only. The indexer skips update tracking, reducing storage I/O by up to 80% for high-volume event entities.

type Transfer @entity(immutable: true) {
  id: Bytes!
  from: Bytes!
  to: Bytes!
  value: BigInt!
  blockTimestamp: BigInt!
  transactionHash: Bytes!
}

Use Bytes for Entity IDs

Bytes IDs are stored as raw bytes. String IDs require hex encoding/decoding on every load/save. For entities keyed by address or tx hash, Bytes is 2-3x faster.

Set startBlock Correctly

Never index from block 0. Set startBlock to the contract's deployment block or the block of the first relevant event.

# Find deployment block using cast
cast receipt <TX_HASH> --rpc-url $RPC_URL | grep blockNumber

Enable Pruning

indexerHints:
  prune: auto

Prune removes historical entity versions. Subgraphs that do not need time-travel queries should enable pruning.

Minimize Contract Reads

Each try_* call is an RPC request during indexing. Cache values in entities instead of re-reading on every event.

// BAD: reads contract on every Transfer event
let name = contract.try_name();

// GOOD: read once, store in entity
let token = Token.load(event.address);
if (token == null) {
  token = new Token(event.address);
  let name = contract.try_name();
  token.name = name.reverted ? "Unknown" : name.value;
}

Batch Entity IDs

Use event.transaction.hash.concatI32(event.logIndex.toI32()) for unique IDs per event within a transaction. This avoids string concatenation overhead.

Graph Client (Frontend Integration)

Type-safe GraphQL client for querying subgraphs from frontend or Node.js.

Installation

npm install @graphprotocol/client-cli graphql
npx graphclient init

Configuration (.graphclientrc.yml)

sources:
  - name: MySubgraph
    handler:
      graphql:
        endpoint: https://gateway.thegraph.com/api/{api-key}/subgraphs/id/{subgraph-id}

Usage in Application

import { execute } from "../.graphclient";
import { gql } from "graphql";

const GET_TOKENS = gql`
  query GetTokens($first: Int!) {
    tokens(first: $first, orderBy: totalSupply, orderDirection: desc) {
      id
      name
      symbol
      totalSupply
    }
  }
`;

async function fetchTokens(): Promise<void> {
  const result = await execute(GET_TOKENS, { first: 10 });
  if (result.errors) {
    throw new Error(`Query failed: ${result.errors[0].message}`);
  }
  const tokens = result.data.tokens;
  for (const token of tokens) {
    console.log(`${token.symbol}: ${token.totalSupply}`);
  }
}

Subgraph Composition (Multiple Data Sources)

Index multiple contracts in a single subgraph.

dataSources:
  - kind: ethereum
    name: USDC
    network: mainnet
    source:
      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48"
      abi: ERC20
      startBlock: 6082465
    mapping:
      kind: ethereum/events
      apiVersion: 0.0.9
      language: wasm/assemblyscript
      entities:
        - Token
        - Transfer
      abis:
        - name: ERC20
          file: ./abis/ERC20.json
      eventHandlers:
        - event: Transfer(indexed address,indexed address,uint256)
          handler: handleTransfer
      file: ./src/mapping.ts

  - kind: ethereum
    name: WETH
    network: mainnet
    source:
      address: "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2"
      abi: ERC20
      startBlock: 4719568
    mapping:
      kind: ethereum/events
      apiVersion: 0.0.9
      language: wasm/assemblyscript
      entities:
        - Token
        - Transfer
      abis:
        - name: ERC20
          file: ./abis/ERC20.json
      eventHandlers:
        - event: Transfer(indexed address,indexed address,uint256)
          handler: handleTransfer
      file: ./src/mapping.ts

Both data sources share the same mapping file and entity types. The mapping code must handle both contracts.

Grafting (Resume from Existing Subgraph)

Deploy a new subgraph version that starts from an existing subgraph's indexed state instead of re-indexing from scratch.

features:
  - grafting
graft:
  base: QmExistingSubgraphDeploymentId
  block: 18500000

Grafting rules:

• base is the deployment ID (Qm... hash) of the source subgraph
• block is the block to graft from -- the new subgraph inherits all entity state at this block
• Grafting is for development iteration -- production subgraphs should be indexed from scratch
• Grafted subgraphs cannot be published to the decentralized network

Common File Structure

my-subgraph/
  abis/
    ERC20.json
    Factory.json
  src/
    mapping.ts          # AssemblyScript event handlers
    factory.ts          # Factory pattern handlers
    helpers.ts          # Shared utility functions
  generated/
    schema.ts           # Auto-generated from schema.graphql (do not edit)
    ERC20/ERC20.ts      # Auto-generated from ABI (do not edit)
  schema.graphql        # Entity definitions
  subgraph.yaml         # Manifest
  package.json
  tsconfig.json

Indexing Alternatives

The Graph is the standard for decentralized indexing, but it's not always the best fit. Consider alternatives for specific use cases.

When NOT to Use The Graph

• Small projects (<5 entity types, simple queries): Setup overhead exceeds benefit
• TypeScript-first teams: AssemblyScript mapping layer adds friction
• Real-time data (<2 second freshness): Subgraph indexing has inherent latency (block confirmation + indexing time)
• Complex joins/aggregations: GraphQL limitations make multi-entity analytics painful
• Rapid iteration: Subgraph deployment and syncing takes minutes to hours

Ponder

TypeScript-native indexing framework. Write handlers in TS (not AssemblyScript), get automatic GraphQL API, and iterate with hot reloading.

// ponder.config.ts
import { createConfig } from "@ponder/core";
import { http } from "viem";
import { ERC20Abi } from "./abis/ERC20";

export default createConfig({
  networks: {
    mainnet: { chainId: 1, transport: http(process.env.PONDER_RPC_URL_1) },
  },
  contracts: {
    ERC20: {
      network: "mainnet",
      abi: ERC20Abi,
      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48", // USDC
      startBlock: 6_082_465,
    },
  },
});

// src/ERC20.ts — event handler in TypeScript (not AssemblyScript)
import { ponder } from "@/generated";

ponder.on("ERC20:Transfer", async ({ event, context }) => {
  const { Account, Transfer } = context.db;

  await Account.upsert({ id: event.args.from });
  await Account.upsert({ id: event.args.to });

  await Transfer.create({
    id: event.log.id,
    data: {
      from: event.args.from,
      to: event.args.to,
      amount: event.args.value,
      timestamp: Number(event.block.timestamp),
    },
  });
});

Why choose Ponder: 10-15x faster iteration (hot reload, no deploy wait), full TypeScript (no AssemblyScript learning curve), viem types, automatic GraphQL API, runs locally or self-hosted. Best for teams that want subgraph-like indexing without the AssemblyScript tax.

Dune Analytics

SQL-based blockchain analytics platform. Best for historical analysis, cross-protocol queries, and dashboards -- not real-time application backends.

-- Top USDC transfers in last 24 hours
SELECT
  "from",
  "to",
  value / 1e6 AS usdc_amount,
  block_time
FROM erc20_ethereum.evt_Transfer
WHERE contract_address = 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48
  AND block_time > now() - interval '24 hours'
ORDER BY value DESC
LIMIT 20;

Why choose Dune: Pre-indexed data across all major chains, SQL interface, community dashboards, no infrastructure to manage. Not suitable for: real-time dApp backends (query latency 5-30s), programmatic API access requires paid plan.

Direct RPC + Multicall3

For simple read-heavy patterns, skip indexing entirely. Batch onchain reads with Multicall3.

import { createPublicClient, http } from 'viem';
import { mainnet } from 'viem/chains';

const client = createPublicClient({
  chain: mainnet,
  transport: http(),
});

// Batch multiple reads in a single RPC call
const results = await client.multicall({
  contracts: [
    { address: tokenA, abi: erc20Abi, functionName: 'balanceOf', args: [user] },
    { address: tokenB, abi: erc20Abi, functionName: 'balanceOf', args: [user] },
    { address: pool, abi: poolAbi, functionName: 'slot0' },
    { address: pool, abi: poolAbi, functionName: 'liquidity' },
  ],
});

Multicall3 is deployed at 0xcA11bde05977b3631167028862bE2a173976CA11 on 70+ chains (same address everywhere via CREATE2).

Why choose direct RPC: Zero infrastructure, real-time data, simple reads. Not suitable for: historical queries, event aggregation, complex entity relationships.

Decision Matrix

References

• Subgraph Studio: https://thegraph.com/studio/
• Official docs: https://thegraph.com/docs/en/
• Graph Explorer (find existing subgraphs): https://thegraph.com/explorer
• AssemblyScript docs: https://www.assemblyscript.org/
• graph-ts API reference: https://thegraph.com/docs/en/developing/graph-ts/api/
• Supported networks: https://thegraph.com/docs/en/developing/supported-networks/