Security, Testnets & Safe Habits

Faucets, testnet workflow, signature phishing, approvals and the habits that keep student wallets safe.

9 min read·4 quiz questions

Work on testnets first

Base Sepolia coins have no value, so mistakes are free. Keep a dedicated browser profile and a throwaway seed phrase for class work, and never reuse it for real funds.

•Get testnet ETH from a faucet, not an exchange.
•Verify chain ID (Base Sepolia = 84532) before signing.
•Label your test account clearly in the wallet.

Read what you sign

Malicious dApps ask for blanket approvals or off-chain signatures (Permit, Seaport orders) that move assets later. Check the domain, the spender, the amount, and prefer exact-amount approvals. Revoke stale allowances.

Common student mistakes

Pasting a seed phrase into a website, sending to the wrong chain, trusting an address from chat, or forgetting to leave gas for the unstake transaction. Always test the flow with a tiny amount first.

Key terms

Faucet: Service that drips free testnet coins for development.
Chain ID: Numeric network identifier; Base Sepolia is 84532.
Approval: Allowance letting a contract spend your tokens.
Signature phishing: Tricking a user into signing an off-chain message that authorises theft.

Chapter quiz

4 questions · pass mark 75%

1. Which chain ID is Base Sepolia?
2. A site asks for your 12-word seed phrase to 'verify' your wallet. You should…
3. Safest approval habit?
4. Why keep a separate wallet for class labs?

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