❓ Problem: Debugging Move on Sui feels like searching for a needle in a haystack. Errors are cryptic, stack traces look alien, and reproducing bugs is tough.

💡 Why this happens: On-chain failures behave differently than traditional code errors. Without a clear debug loop, fixing them can feel like guesswork.

🎯 Goal: Equip you with tools, logs, and workflows to reproduce, debug, and fix issues with confidence.

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🛠️ 1) Use Local Deterministic Devnets

• Spin up a single-node local devnet with fixed seed accounts for reproducibility.
• Commands like sui start or run-local-network.sh work great.
• Benefit: Test without network noise! 📚 docs.sui.io

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🧪 2) Unit Tests & Move Test Harness

• Run:

sui move test

• Write tests for edge cases & expected reverts.
• Faster feedback = faster bug squashing. 🐛

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🔍 3) Transaction Simulation & Logging

• Simulate before you submit using SDK APIs.
• Inspect transaction effects to see: ✅ Created objects ✅ Mutated objects ✅ Deleted objects
• Read emitted events to trace what happened step-by-step. 📚 Mysten Labs TS SDK Docs

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📄 4) Use Node Logs & Debug Flags

• Run nodes with verbose logging to get detailed execution traces.
• Check Sui repo for debug flag usage.
• If you can, peek at validator logs for tricky issues.

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🪜 5) Step-by-Step Debug Flow

1. Reproduce locally with the same object IDs/inputs.
2. Write a sui move test that mimics the transaction.
3. Inspect transaction effects & logs.
4. Add assertions to pinpoint wrong state changes.
5. Fix → Test → Repeat until stable.