I Made an AI Agent That Codes Like a Senior Developer, Here's How


Hey Reader,

Ever Wish You Had a Senior Engineer Reviewing Your Code 24/7? ๐Ÿง โ€‹
Now you do and itโ€™s powered by AI.

This is Part 1 of my new AI Agent Series where weโ€™re building and deploying real AI agents that can think, analyze, and act like a senior software engineer ๐Ÿค“.

This project is called AI Code Reviewer and itโ€™s not just a fancy chatbot. It remembers past messages, gives contextual feedback and helps you ship better code, faster.

Here's the Tech Stack:

โ†’ โšก Next.js 15 + React 19

โ†’ ๐Ÿง  Convex Agents + Agentic Workflows

โ†’ ๐Ÿค– GPT-4o-mini via OpenAI

โ†’ ๐Ÿ“œ TypeScript + Zod for safe inputs/outputs

โ†’ ๐ŸŽจ Tailwind CSS v4 + Shadcn UI

You can build it in less than an hour with this step-by-step guide and codebase.

๐ŸŽฅ Watch the walkthrough here:

video previewโ€‹

๐Ÿฟ Weekly Snack: Create Your First AI Agent

๐Ÿค– What Are Agents, Really? I like to think of AI agents as smart minions. You give them a goal, some memory, and a few tools and they go off to work.

Theyโ€™re not like chatbots that just reply.

Agents think, decide, and act โ€” and they improve with each interaction. They can call APIs, remember context, and adapt to messy tasks.

In this project, we define our minion aka Agent like this:

This Agent is a AI Coding Agent.

It will give feedback, catch bugs and improve your code quality like a Senior Software Engineer.

โ†’ Agent is from Convexโ€™s AI SDK. It wraps everything needed to create a smart, stateful minion.

โ†’ chat uses GPT-4o-mini to process conversations.

โ†’ textEmbedding allows semantic understanding and memory across sessions.

โ†’ instructions tell the minion what role to play (in this case, act like a senior code reviewer).

โ†’ tools is where you can pass in API functions your agent can use, like file search, web search or documentation lookups.

๐Ÿ”ฅ Agent is Powered by OpenAI and Convexโ€‹

If you'd like a more in-depth explanation then check out these video series

๐Ÿš€ Latest Frontend News

โ€‹AI Code Review Agent Tweet (Share it further)

React introduced a few exciting features in experimental mode such as,

  • Shipped View Transitions that makes it easier to add animations to UI transitions in your app
  • Shipped Activity to allow components to be visually hidden and deprioritized, preserving UI state

React is working on an Official MCP Server, check it outโ€‹

Upstash introduced Caching for Drizzle ORM, with automatic invalidation and faster queries

โ€‹Next.js Deployment Docs just got a major revamp โ€” removing Vercel bias and giving more balanced provider guidance ๐Ÿ‘

Want to build your agents on the edge? Check out this Platform For Building Agents on CloudFlareโ€‹
โ€‹

FREE

๐Ÿ”ฅ I just made a few lessons completely free in the Modern Full Stack Next.js Course on Mastering Data Fetching, dive into real-world examples for free.
โ€‹

ICYMI, we covered The Most Overlooked Feature in Next.js 15 in last week's newsletter.

๐ŸŽฅ Weekly Youtube Videos

Check it out and subscribe to my channel โ†—๏ธ for more Frontend, Leadership and Career Development content.

Stop using v0, try this Instead

video previewโ€‹

I shipped my First SaaS, Here's What I learned

video previewโ€‹

What do you think of today's Newsletter? Simply click on one of the links below.

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Ankita Kulkarni

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