Tips to Write Optimized and Secure Move Code on Aptos: A Practical Guide

In this blog, we'll walk through practical tips and best practices that will elevate your Move development skills.

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1. Master the Power of Resources

Resources are linear types that represent assets or state. They cannot be copied or discarded accidentally. Use them to store key user-specific data like balances or ownership records.

Use move_to and borrow_global_mut to manage these resources effectively.

👉 Tip: All your storage logic and entry functions should be organized inside a Move module. Think of a module as the smart contract that holds your logic, structs, and public interfaces.

Example:

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2. Always Declare acquires

When your function interacts with global storage, explicitly declare the resource in the acquires clause. This helps the Move VM verify resource safety.

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3. Reduce Storage Access Overhead

Reading from global storage costs gas. Avoid accessing the same resource multiple times.

❌ Inefficient:

✅ Efficient:

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4. Use Checked Math

Avoid overflows by using checked_add, checked_sub, and checked_mul. These functions return Option and ensure math safety.

let new_amount = a.checked_add(b).expect("overflow");

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5. Avoid Vectors in Global Storage

Vectors are not ideal for global storage as they require copying the entire vector on modification. Prefer resource-per-address mappings for user data.

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6. Minimize Resource Footprint

Store only necessary fields. Instead of storing complete objects, store references or IDs where possible. Smaller resources = cheaper reads and writes.

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7. Use Constants and Error Codes

Centralize all error codes as constants and use them in assertions.

const E_NOT_INITIALIZED: u64 = 1; assert!(exists<Balance>(addr), error::invalid_argument(E_NOT_INITIALIZED));

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8. Safe Initialization Patterns

Ensure users initialize their resources with an initialize() function before any interaction

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9. Gas Optimization Summary

Here are some easy ways to write code that uses less gas:

✨ Tip: Only check exists<T> once and store the result in a variable instead of checking it again.

✨ Tip: Don’t borrow the same resource more than once .Just use a let variable to reuse it.

✨ Tip: Keep your main entry functions clean by minimizing complex if or match branches.

✨ Tip: Store only essential data in smaller resource structs reduce gas costs on reads and writes.

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10. Security Best Practices

• Use signer::address_of to check identity

• Validate all function inputs

• Restrict mint, burn, or transfer access

• Use clear assertion messages

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11. Add Events for Transparency

Events improve transparency and enable off-chain analytics.

struct MintEvent has drop, store { amount: u64, } public fun mint(...) { emit_event<MintEvent>(&event_handle, MintEvent { amount }); }

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12. Unit Testing is Essential

Write unit tests using #[test] for every entry and private function.
Run tests with:

aptos move test

Cover edge cases and expected errors to prevent regressions.

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13. Upgrade with Feature Flags

Use a version constant or config resource to control logic upgrades gracefully.

const VERSION: u64 = 1;

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14. Separate Dev Modules

Keep main modules production-safe. Place debug functions and test mints in a separate module that’s only deployed on devnet or testnet.

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Conclusion

Writing optimized Move code takes practice and attention to detail. By applying these tips from minimizing storage reads to writing secure, testable logic ,you’ll produce efficient and secure smart contracts ready for real-world Aptos deployments.

Want more tips? Follow this blog or reach out with your Move questions!