Understanding Gas Optimization Beyond the Basics

Most developers stop at basic gas optimization—using uint256 instead of smaller types, packing storage slots. But there's a whole level beyond that which separates okay contracts from genuinely efficient ones.

Take event emission, for example. Lots of developers don't realize that indexed parameters in events cost more gas but make off-chain querying exponentially faster. When should you index? When your application needs to filter by that parameter frequently. Otherwise, you're just burning user money.

Another thing—storage patterns matter way more than most tutorials suggest. SSTORE operations are expensive. Really expensive. If you're writing to storage multiple times in a single transaction, you need to rethink your approach. Cache in memory, write once at the end.

The Security Mindset: What Auditors Actually Look For

Security in smart contracts isn't about memorizing a list of vulnerabilities. It's about developing a mindset where you constantly ask "what could go wrong here?"

Reentrancy gets all the attention because of high-profile hacks. But the most common vulnerabilities I see in audits? Access control mistakes and integer overflow issues (yes, even post-Solidity 0.8.0, when developers use unchecked blocks incorrectly).

Here's something nobody talks about enough: external contract calls. Every time you call another contract, you're trusting code you don't control. What if that contract's been upgraded? What if it has a fallback function that does something unexpected?

Defense in depth means assuming every external interaction is potentially hostile. Check return values. Use reentrancy guards even when you think you don't need them. Validate all inputs, even from contracts you "trust."

Building for Multiple Chains: Not Just Copy-Paste

Multi-chain deployment sounds simple until you actually do it. Ethereum, Polygon, Arbitrum—they all run EVM, right? Just deploy the same bytecode everywhere?

Wrong. Block times differ. Gas costs vary wildly. Polygon's faster blocks mean you can't rely on block numbers for timing. Arbitrum's sequencer adds complexity to transaction ordering assumptions.

And then there's the tooling differences. What works perfectly on Ethereum might fail on a Layer 2 because of subtle differences in how certain opcodes behave or how contract verification works.

Our multi-chain materials walk through these differences with actual deployment examples. Not hypothetical scenarios—real contracts we've deployed across six different networks, with all the gotchas we discovered the hard way.