A Solidity developer writes smart contracts for Ethereum and other chains that run the Ethereum Virtual Machine (EVM). This guide covers the language features a developer should know in 2026, the standard tools, the security patterns, typical pay, and the questions to ask a candidate or a firm.
It is about the developer and the craft of Solidity development; for project planning, read the guides to smart contract development and Ethereum smart contract development.
What a Solidity developer does
A Solidity developer designs, writes, tests and deploys contracts that hold and move other people's money. The work usually covers these tasks:
- Translating product rules into contract logic, such as token supply, fees, vesting or lending terms.
- Writing unit tests, fuzz tests and invariant tests.
- Writing deployment scripts and verifying the source code on block explorers.
- Designing upgrade paths and admin roles.
- Working with auditors and fixing the issues they report.
- Supporting front-end and back-end developers who call the contracts.
How Solidity differs from ordinary programming
- Deployed code is usually permanent. Nobody can edit bytecode after deployment, so an upgrade needs a proxy pattern chosen before launch, and that pattern brings its own risks.
- Every operation costs gas. A storage write costs far more than a memory operation or a calculation, so the developer must plan the data layout with this cost in mind.
- All data is public. A
privatevariable is hidden only from other contracts, and anyone can read the storage directly. Pending transactions are also visible in the mempool, so other parties can front-run them. - An external call hands over control. When your contract calls another contract, the other contract can call back into yours before your function finishes, which is the cause of reentrancy bugs.
- Execution must be deterministic. Contracts have no built-in randomness, no network calls and no floating-point numbers, so off-chain data arrives through oracles.
Solidity language features to know in 2026
Solidity is still on the 0.8 line, and version 0.8.37 came out in September 2026. Version 0.8.31 was the first version to mark features that a future 0.9.0 release will remove. A developer should know these features:
| Feature | What it does |
|---|---|
| Checked arithmetic (since 0.8.0) | Overflow and underflow revert by default, so SafeMath is no longer needed. An unchecked block turns the check off to save gas where overflow cannot happen. |
| Custom errors | revert InsufficientBalance(available, required) costs less gas than a revert string and gives tools structured data. |
immutable and constant | The compiler writes these values into the bytecode, so reading them needs no storage read. |
| Transient storage (EIP-1153) | Data that the chain clears at the end of each transaction. Solidity supports transient state variables since 0.8.28. Developers use them for cheap reentrancy locks. |
| User-defined value types | Typed wrappers, such as a Price type, catch unit mix-ups at compile time. |
| ERC-7201 namespaced storage | A storage layout that keeps upgradeable contracts from overwriting each other's slots. Version 0.8.35 added an erc7201 builtin that computes the base slot. |
| The via-IR pipeline | A second compilation path that can optimize more and avoids most "stack too deep" errors. Builds take longer. |
Production code should pin one compiler version, so check the official Solidity documentation and its list of known compiler bugs for that version. Versions 0.8.34, 0.8.36 and 0.8.37 each fixed security bugs in the compiler.
Chain upgrades also change what developers must know. The Pectra upgrade of May 2025 added EIP-7702, which lets an ordinary wallet account run contract code. A check such as msg.sender == tx.origin no longer proves that the caller is a plain wallet that cannot run code.
The Solidity developer toolchain
| Tool | What it does |
|---|---|
| Foundry (forge, cast, anvil) | Runs tests written in Solidity, with built-in fuzzing, invariant testing and mainnet forking. Many security-focused teams use it as their main tool. |
| Hardhat 3 | Runs Solidity tests compatible with Foundry and TypeScript tests in one project. Teams with a TypeScript front end often use it for deployment scripts. |
| OpenZeppelin Contracts | Audited code for ERC-20, ERC-721, ERC-1155, ERC-4626, access control and upgradeable proxies. |
| Slither and linters | Static analysis that runs in continuous integration on every pull request. |
| Formal verification and symbolic execution | Mathematical checks of key rules in high-value DeFi protocols. |
Security patterns a Solidity developer should apply
- Checks-effects-interactions. Check the inputs, update your own state, and only then call other contracts. Add a reentrancy guard to every function that moves value.
- Explicit access control. Give each privileged action a role, and put powerful roles behind a multisig and a timelock.
- Pull payments. Let users withdraw their funds instead of looping over a list of recipients and sending to each one.
- Bounded loops. Never loop over an array that users can grow without limit, because an attacker can grow such an array until the function runs out of gas.
- Safe price data. Do not use one DEX spot price as an oracle, because an attacker can move that price inside one transaction with a flash loan.
- Safe token handling. Use the SafeERC20 wrapper, because some tokens return no boolean, charge a fee on transfer, or change balances on their own.
- Invariant tests. Write down rules that must always hold, such as "total supply equals the sum of balances", and fuzz the contract against them.
Contracts that hold value still need an independent smart contract audit before mainnet.
Gas optimization
To save gas, developers pack small variables into one storage slot, copy storage values into memory before a loop, use calldata for read-only arrays, and emit events instead of storing history. Inline assembly can save more gas, but it skips the compiler's safety checks and makes audits harder. On layer 2 networks, data posting makes up most of the cost and execution is cheap, so small execution savings there change the fee very little.
Solidity developer salary and rates
Pay data for Solidity roles varies by source and by method. These figures come from job sites in mid-2026:
| Source | Figure | Basis |
|---|---|---|
| ZipRecruiter (July 2026) | About $121,000 a year, or $58 an hour | US average from job ads |
| Crypto.jobs (June 2026) | About $120,000 to $155,000 for 0 to 2 years; $155,000 to $205,000 for 3 to 5 years; $215,000 to $250,000 for 5+ years | Crypto job listings |
| Web3.career (2026) | About $150,000 average, with a range of $65,000 to $257,000 | Web3 job listings, worldwide |
The three sites collect different data, so the figures show a range, not one market price.
How to evaluate a Solidity developer or a development firm
- Ask for public code: deployed and verified contracts, or repositories with tests, and read the tests as well as the contracts.
- Ask how they would make a given contract upgradeable. A strong answer names the risks, such as storage collisions and uninitialized implementation contracts.
- Ask them to explain a past exploit, such as a reentrancy or oracle attack, and how they would have prevented it.
- Check whether they use OpenZeppelin for standard functions, because a developer who writes a token from scratch adds risk with no benefit.
- Check that their plan includes time for fuzzing, invariant tests and an external audit.
- Ask about audit reports for their past contracts and how they fixed the findings.
Some projects need a narrower specialist; see the guides to DeFi smart contract development and ERC-20 token development.
Frequently asked questions
Is Solidity only for Ethereum?
No. Solidity compiles to EVM bytecode, so the same contracts run on Ethereum layer 2 networks, BNB Smart Chain, Polygon PoS, Avalanche C-Chain, Hedera and other EVM chains. Opcodes and gas rules differ slightly between chains, so test on each target chain.
Should I use Solidity or Vyper?
Solidity has more libraries, more auditors and more developers, while Vyper has a smaller feature set by design, and some large protocols such as Curve use it. Most teams choose Solidity because hiring and tools are easier.
How long does it take to become a Solidity developer?
An experienced programmer can write working contracts within a few weeks, but writing contracts safe enough to hold large sums takes much longer. Most of that time goes into studying past exploits, testing methods and the EVM itself.
Can a Solidity developer fix a bug after deployment?
Only if the contract has an upgradeable proxy or a planned migration path. Otherwise the developer deploys a new contract and users must move to it, which takes time and can cost user trust.