Ribhav

Posted on Jan 8 • Originally published at Medium

Vibecoding On‑Chain — Using AI to Prototype Solidity Contracts (Safely)

#crypto #blockchain #vibecoding #beginners

I used to open Remix, stare at a blank Solidity file, and freeze. No idea where to start. So I did what everyone says: “just write more code.” I copied patterns from tutorials, tweaked a few lines, hit deploy…
And still felt like I wasn’t actually learning how smart contracts worked.

The weird part?

It wasn’t a lack of practice.
It was how I was practicing.

One day I tried something different:

I stopped starting from scratch — and started “vibecoding” with AI instead.
Not to cheat.
To see what would happen if I treated AI as a rough sketch artist and myself as the editor.

That experiment turned into today’s article.

This is Day 28 of the 60‑Day Web3 journey, still in Phase 3:
Development. The goal for today is to understand what “vibecoding”
is, how to use AI tools to scaffold Solidity contracts, and how to
review and harden that code so it’s actually safe to deploy.

1. What is “vibecoding” in Web3?

“Vibecoding” is the idea of building from vibes and prompts instead of blank files: you describe what you want in natural language and let an AI tool generate the first version of your code.

In Web3, that means using AI to scaffold Solidity contracts, test cases, or even full dApp skeletons so you can iterate on ideas much faster.

The mindset shift:

Traditional approach: “Open VS Code → stare at empty file → fight the compiler.”
Vibecoding approach: “Describe the contract in detail → get a first draft → review, fix, and improve.”

AI becomes a collaborator that handles boilerplate while you stay in charge of architecture, safety, and product thinking.

2. Why vibecoding is perfect after basics

In the last two days you:

Learned Solidity syntax, variables, functions, and how contracts expose state.
Upgraded your Web3 Journey Logger with arrays, mappings, structs, and events to handle multiple entries and multiple users.

Now vibecoding lets you:

Turn that knowledge into better prompts (for example: “use mapping(address => Entry[]) with a struct” instead of “write an NFT for me”).
Use AI as a partner: it writes boilerplate; you handle reviews, invariants, and edge cases.
Practice reading and critiquing Solidity, which is one of the most important skills for anyone who wants to do DevRel, audits, or technical content.

You’re not skipping learning; you’re using AI to remove grunt work so you can spend more time understanding what the code actually does.

3. How to prompt AI for a contract

Good vibecoding starts with good prompts. A vague “write a staking contract” is a recipe for weird, unsafe code.

A solid prompt usually:

Describes the goal of the contract.
Specifies the data model (structs, mappings, arrays).
Mentions events and access control.
States the Solidity version.

Example prompt:

“Write a Solidity 0.8.x contract called StudyBuddy where:

– users can log study sessions with topic (string) and minutes (uint256)

– each user can record many sessions

– use a struct Session { string topic; uint256 minutes; } and mapping(address => Session[])

– emit an event whenever a new session is logged

– include view functions to read a user’s total sessions and a session by index

– avoid using tx.origin, and use SPDX + a recent 0.8 compiler pragma”

This kind of prompt pushes the AI towards patterns you already understand from the Journey Logger V2, just in a different context.

4. Example: vibecoding a `StudyBuddy` contract

Assume you feed the prompt above into your AI tool. A reasonable output might look like this:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

contract StudyBuddy {
    struct Session {
        string topic;
        uint256 minutes;
    }

    mapping(address => Session[]) private sessionsByUser;

    event SessionLogged(address indexed user, string topic, uint256 minutes, uint256 index);

    function logSession(string calldata _topic, uint256 _minutes) external {
        Session memory newSession = Session({topic: _topic, minutes: _minutes});
        sessionsByUser[msg.sender].push(newSession);

        uint256 index = sessionsByUser[msg.sender].length - 1;
        emit SessionLogged(msg.sender, _topic, _minutes, index);
    }

    function getSession(address _user, uint256 _index)
        external
        view
        returns (string memory topic, uint256 minutes)
    {
        require(_index < sessionsByUser[_user].length, "Index out of bounds");
        Session storage s = sessionsByUser[_user][_index];
        return (s.topic, s.minutes);
    }

    function getSessionCount(address _user) external view returns (uint256) {
        return sessionsByUser[_user].length;
    }
}

Why this is a nice vibecoded example:

Reuses ideas you already know: struct + mapping + dynamic array.
Uses events for logging, which is good practice.
Avoids obviously dangerous patterns.
Is small enough to reason about line by line.

But vibecoding doesn’t end when the AI prints code. The real work starts now: review, compare, and test.

5. The 3 rules of safe vibecoding

Rule 1: Assume the AI is wrong until proven right

AI code generators copy patterns they’ve seen, but they don’t “understand” economic incentives or attack surfaces.

Baseline checklist for any AI‑generated contract:

SPDX license and a recent pragma solidity ^0.8.x; at the top.
No tx.origin checks for authentication.
No naive use of block.timestamp for randomness.
External calls (if any) are carefully handled (for example, avoiding reentrancy patterns).
Functions have correct visibility and view/pure where appropriate.

Even if the contract compiles, that doesn’t mean it’s safe.

Rule 2: Compare against known‑good patterns

For standard functionality (tokens, access control, pausing, etc.), you can sanity‑check AI output against:

OpenZeppelin reference implementations and docs.
Official Solidity examples and documentation.
Well‑audited open source contracts on Etherscan or GitHub.

If the AI invented something you’ve never seen anywhere else, treat it with suspicion. Ask it why it made a choice, or explicitly prompt it to follow a known pattern.

Rule 3: Add tests and manual review

Even for small demo contracts, aim for:

Unit tests (or Foundry/Hardhat tests) that:
- Call each function with typical inputs.
- Try edge cases (index out of bounds, zero values, maximum values).
- Check that events are emitted correctly.
Manual reasoning about:
- Who can call each function and what they can change.
- How data grows over time (could someone spam storage?).
- Whether there are any hidden assumptions (for example, “one user will only have a few sessions”).

AI is great at generating draft code and even draft tests, but humans are responsible for understanding the behavior and risks.

6. How vibecoding helps you as a learner and future DevRel

For someone aiming at DevRel or technical education, vibecoding is a superpower:

You can prototype tutorials faster: generate a demo contract, then turn the act of reviewing/fixing it into content.
You learn by debugging AI: every time you catch a mistake in AI output, your mental model of Solidity gets sharper.
You build empathy for beginners: many new devs will rely heavily on AI; your role can be showing them how to use it safely instead of blindly trusting it.

A content pattern you can reuse:

Start from a plain‑English idea (“I want to track X on‑chain”).
Prompt AI for a contract.
Walk through the code in an article or video, highlighting:
- What’s good.
- What’s missing.
- What you changed before deploying.
Deploy the improved version to a testnet and give readers a challenge to extend it.

In doing so, you position yourself not just as “someone who writes Solidity,” but as a guide who helps others navigate the new AI‑assisted way of building.