Workshop: first contract

Run a 75-minute workshop where participants write, deploy, verify and call their first smart contract on BOT Chain testnet. Timings are suggestions. Participants need to have finished the setup workshop or the day-one checklist.

What participants build

A Counter contract, deployed to testnet, verified on BOTScan and called from the terminal. The steps follow the quickstart, which you can project on screen.

Outline

Time	Segment	What happens
0:00	Why contracts	A contract is code at an address. Anyone can call it; only transactions change it.
0:05	Create the project	`forge init hello-bot`. Walk through `src/Counter.sol` line by line.
0:15	Point at BOT Chain	Edit `foundry.toml`: add the testnet RPC and `evm_version = "cancun"`. Explain why the EVM version matters.
0:20	Build and test	`forge build` and `forge test`. Show a failing test, then fix it.
0:30	Deploy	`forge create ... --broadcast`. Open the transaction on BOTScan.
0:40	Verify	`forge verify-contract` with the Blockscout verifier. Show the Contract tab.
0:50	Call it	`cast send` to increment, `cast call` to read. Explain why reads are free.
0:55	Change it	Participants add a function (for example `decrement`), redeploy and verify.
1:10	Wrap up	Point to templates and example tracks.

Talking points

Testnet only. tBOT has no value. The same commands work on mainnet with real BOT, which nobody needs this weekend.
Gas. Deploying and calling Counter cost about 0.004 tBOT in our test. Show the fee on BOTScan.
Verification. Judges and users trust what they can read. Unverified code is a black box.
The EVM version. BOT Chain doesn’t support Osaka yet. Setting cancun avoids “invalid opcode” errors. See Supported EIPs.

The exercise

Ask participants to add this to Counter and redeploy:

src/Counter.sol

function decrement() public {
    require(number > 0, "Counter: already zero");
    number--;
}

Then call it with cast send $COUNTER "decrement()" --rpc-url bot_testnet --account uzo-dev. Calling it again when the value is 0 shows a revert with the message, which is a good moment to explain errors.

Common problems

Symptom	Fix
`insufficient funds`	Fund the address from `cast wallet address --account uzo-dev`.
Nothing deployed	Missing `--broadcast`.
Verification fails	Used the transaction hash instead of the `Deployed to` address, or verified too soon. Wait and retry.

Done when

Every participant has a verified contract on BOTScan testnet and has called it at least once.

Next steps

AI agent workshop

Planned outline: an agent with on-chain spending limits.

Templates

Start a real project from a working template.

Build your first dApp

Put a web frontend on a contract.

Hackathon kit

Workshops

For organizers

Workshop: first contract

What participants build

Outline

Talking points

The exercise

Common problems

Done when

Next steps

AI agent workshop

Templates

Build your first dApp

​What participants build

​Outline

​Talking points

​The exercise

​Common problems

​Done when

​Next steps

AI agent workshop

Templates

Build your first dApp

What participants build

Outline

Talking points

The exercise

Common problems

Done when

Next steps