deploying-contracts-on-abstract

name

deploying-contracts-on-abstract

description

Deploy smart contracts on Abstract using Foundry (default) or Hardhat. Covers zksolc compilation, deployment, Abscan verification, and testnet faucets for the Abstract Ethereum L2. This skill should be used when deploying or compiling contracts on Abstract, using forge/foundry-zksync, forge build --zksync, forge create --zksync, anvil-zksync, verifying on Abscan, or working with the zkSync compiler on Abstract.

Deploying Contracts on Abstract

Default: Foundry. Abstract uses the ZK Stack VM — contracts must be compiled with zksolc, not standard solc. For Hardhat, see references/hardhat.md. For EVM differences, see references/evm-differences.md.

Foundry Setup

1. Install foundry-zksync

curl -L https://raw.githubusercontent.com/matter-labs/foundry-zksync/main/install-foundry-zksync | bash
foundryup-zksync

Warning: This overwrites standard Foundry. Switch back with foundryup if needed.

2. Create project

forge init my-abstract-project && cd my-abstract-project

3. Configure foundry.toml

[profile.default]
src = 'src'
libs = ['lib']
fallback_oz = true
is_system = false
mode = "3"

[etherscan]
abstractTestnet = { chain = "11124", url = "https://api-sepolia.abscan.org/api", key = "${ABSCAN_API_KEY}" }
abstractMainnet = { chain = "2741", url = "https://api.abscan.org/api", key = "${ABSCAN_API_KEY}" }

4. Compile

forge build --zksync

Outputs to zkout/ (not out/).

Deploy

Store private key securely

cast wallet import myKeystore --interactive

Fund the deployer

• Testnet: Claim from faucets or bridge from Sepolia
• Mainnet: Bridge ETH via Abstract Bridge

Deploy + verify (testnet)

forge create src/Counter.sol:Counter \
  --account myKeystore \
  --rpc-url https://api.testnet.abs.xyz \
  --chain 11124 \
  --zksync \
  --verify \
  --verifier etherscan \
  --verifier-url https://api-sepolia.abscan.org/api \
  --etherscan-api-key ${ABSCAN_API_KEY}

Deploy + verify (mainnet)

forge create src/Counter.sol:Counter \
  --account myKeystore \
  --rpc-url https://api.mainnet.abs.xyz \
  --chain 2741 \
  --zksync \
  --verify \
  --verifier etherscan \
  --verifier-url https://api.abscan.org/api \
  --etherscan-api-key ${ABSCAN_API_KEY}

Constructor arguments

Append --constructor-args <arg1> <arg2> in the order defined in the constructor.

Verify an Existing Contract

forge verify-contract <address> src/Counter.sol:Counter \
  --chain 11124 \
  --etherscan-api-key ${ABSCAN_API_KEY} \
  --zksync

Use --chain 2741 for mainnet. Chain names (abstract-testnet, abstract) also work.

Testing

forge test --zksync

Fork testing against live networks:

forge test --zksync --fork-url https://api.testnet.abs.xyz

Local node:

anvil-zksync
forge test --zksync --fork-url http://localhost:8011

Cheatcode limitation: On Abstract's ZK VM, cheatcodes (vm.prank, vm.roll, etc.) only work at the root test level — not from within contracts being tested.

Decision: Foundry vs Hardhat

Scenario	Use
Solidity-first, fast iteration	Foundry (default)
TypeScript preference	Hardhat (references/hardhat.md)
Existing Hardhat project	Hardhat (references/hardhat.md)
Existing Foundry project	Foundry
Need JS plugin ecosystem	Hardhat (references/hardhat.md)

Gotchas

• All forge commands need --zksync — without it, you get standard EVM bytecode that won't run on Abstract
• foundryup-zksync overwrites standard Foundry — use foundryup to switch back
• Abscan API key required — get one from abscan.org; set via export ABSCAN_API_KEY=<key> or .env
• zkout/ not out/ — compiled artifacts go to a different directory
• Never commit private keys — use cast wallet import or environment variables