As a junior Solidity dev, how deep should I really go into gas optimization during interviews?

Web3Learner_Abaz · 2025-10-28T16:11:23+00:00

I’ve noticed that most junior Solidity interviews don’t dive too heavily into gas micro-optimizations unless it’s for a DeFi or L2 project where every extra transaction cost matters. What interviewers really want to see is whether you understand why gas costs occur — like how storage writes cost ~20k gas or why mappings are usually cheaper than arrays. I once over-optimized to the point where my code became harder to read, and the reviewer said, “Gas is cheap; debugging isn’t.” Since then, I only optimize where it meaningfully affects user costs or state behavior. I want to understand what level of depth interviewers realistically expect from juniors.

As a junior Solidity dev, how deep should I really go into gas optimization during interviews?

Web3Learner_Abaz
@Web3LearnerAbaz

Updated: Oct 30, 2025

Views: 114

I’ve noticed that most junior Solidity interviews don’t dive too heavily into gas micro-optimizations unless it’s for a DeFi or L2 project where every extra transaction cost matters. What interviewers really want to see is whether you understand why gas costs occur — like how storage writes cost ~20k gas or why mappings are usually cheaper than arrays.
I once over-optimized to the point where my code became harder to read, and the reviewer said, “Gas is cheap; debugging isn’t.” Since then, I only optimize where it meaningfully affects user costs or state behavior. I want to understand what level of depth interviewers realistically expect from juniors.

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AnitaSmartContractSensei

@SmartContractSensei • 3w

Juniors who blindly optimize storage to save gas often create logic bugs or attack surfaces. That’s a bigger cost. Mention risks and frequency: “Is this called often enough to justify optimization?” Boom ✅ maturity.

ChainSavant

@ChainSavant • 2w

You nailed it — responsible thinking > fancy tricks. Share your order: safety → clarity → then optimize with data. When you say, “I’d benchmark before optimizing,” that’s a senior mindset already.

ChainMentorNaina

@ChainMentorNaina • 2w

I’ve seen founders filter candidates based on how they talk about optimization. When someone says, “I always optimize gas,” we usually follow up with “where did it matter?” The best candidates explain how they reduced loop iterations, used external functions instead of public, or optimized storage vs memory. It’s not about fancy tricks; it’s about awareness and trade-offs. If you can tie gas usage to UX, transaction cost, and contract security, that’s what really stands out.

Shubhada Pande

@ShubhadaJP • 2w

Good discussion. Most hiring panels don’t expect perfect gas optimization—they look for awareness of design efficiency. Knowing when to optimize matters more than chasing every opcode.

For context, this explainer covers how gas optimization really impacts smart contract performance → [https://artofblockchain.club/discussion/what-is-gas-optimization-in-smart-contracts-and-how-does-it-reduce

You can also explore common Solidity pitfalls here → [https://artofblockchain.club/discussion/struggling-with-solidity-pitfalls-in-interviews-need-help

and take this short gas fees quiz before interviews → [https://artofblockchain.club/quiz/gas-fees-in-ethereum-are-paid-for].