Core Protocol

Smart Contract Developer

Writes, tests, and deploys immutable code that powers decentralized financial logic and asset transfers.

Level: MidMode: High-code#Solidity#Security#EVM

Next action

Build your Web3 proof-of-work. Start contributing and prepare for interviews based on real scenarios.

Role Guide Progress

Lane Type

Core Protocol

Seniority Level

Mid

Execution Mode

High-code

1. Role Overview

The backbone of the Web3 industry. You design decentralized finance (DeFi) logic, standard tokens (ERC-20/ERC-721/ERC-1155), and governance systems (DAOs) holding asset values up to millions of dollars.

2. Daily Work

What you will actually do most weeks

Writing efficient and secure smart contract code using Solidity or Rust

Writing unit tests, integration tests, and fuzzing tests intensively using the Foundry framework

Optimizing gas usage (Gas Optimization) on every function execution

Coordinating with external security auditors to fix vulnerability gaps found

Expected Outputs & Deliverables

Deployed and verified smart contracts on mainnet

Automated test suites with code coverage above 90%

Technical contract architecture documentation and interface specifications (ABIs)

3. Skills & Tools

Must-Have Skills

Deep mastery of Solidity (EVM) or Rust (Solana/Near/Polkadot)

Understanding of Ethereum Virtual Machine architecture (memory, storage, calldata, stack)

Knowledge of security standards and crypto attack vectors (Reentrancy, Flash Loan Attack, Front-running)

Basic financial mathematics for DeFi protocol implementation

Ecosystem Tools

Foundry / Forge / AnvilHardhatSlither / Aderyn (Static Analysis)Git & GitHubEtherscan / Tenderly

4. Proof-of-Work & Prep

Actionable Proof-of-Work

Public GitHub repository containing custom smart contract projects with neat Foundry test structures

Bug bounty findings report or code contributions to well-known open-source protocols on GitHub

Self-Study Prep

Complete security coding challenges like Ethernaut (OpenZeppelin) or Damn Vulnerable DeFi
Master the Foundry framework (Forge for tests, Cast for RPC interaction, Anvil for local node)
Study source code from industry-standard protocols like Uniswap V2/V3, Aave, or OpenZeppelin Contracts

5. Apply & Interview

Application Strategy

Perform self-code reviews or find potential gas optimizations from the target company's open-source contracts, then submit a Pull Request (PR)

Apply via their GitHub repository or contact the Lead Smart Contract Engineer directly attaching your Foundry portfolio

Interview Prompts

"Technically explain the difference between call, delegatecall, and staticcall in Solidity."

"How do you prevent reentrancy vulnerabilities in a staking contract without relying solely on OpenZeppelin's ReentrancyGuard?"

"What is the gas cost difference between storing data in memory versus storage, and when should you use calldata?"

6. Guide Roadmap

Step 1

Solidity & EVM Deep Dive

Master Solidity syntax, EVM memory management, and OpenZeppelin token standards.

Step 2

Foundry Testing & Optimization

Proficient in writing unit tests, fuzzing, invariant testing, and gas optimization.

Step 3

Security & Vulnerability Mastery

Complete Ethernaut challenges and understand prevention methods for common exploits.

Step 4

Open Source Contribution & Apply

Build a strong GitHub portfolio and apply to Web3 engineering teams.