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? πŸ§ β€‹
Now you do and it’s powered by AI.

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

This project is called AI Code Reviewer and it’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:

β†’ ⚑ Next.js 15 + React 19

β†’ 🧠 Convex Agents + Agentic Workflows

β†’ πŸ€– GPT-4o-mini via OpenAI

β†’ πŸ“œ TypeScript + Zod for safe inputs/outputs

β†’ 🎨 Tailwind CSS v4 + Shadcn UI

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

πŸŽ₯ Watch the walkthrough here:

video preview​

🍿 Weekly Snack: Create Your First AI Agent

πŸ€– 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.

They’re not like chatbots that just reply.

Agents think, decide, and act β€” 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.

β†’ Agent is from Convex’s AI SDK. It wraps everything needed to create a smart, stateful minion.

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

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

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

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

πŸ”₯ Agent is Powered by OpenAI and Convex​

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

πŸš€ Latest Frontend News

​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 out​

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

​Next.js Deployment Docs just got a major revamp β€” removing Vercel bias and giving more balanced provider guidance πŸ‘

Want to build your agents on the edge? Check out this Platform For Building Agents on CloudFlare​
​

FREE

πŸ”₯ 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.
​

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

πŸŽ₯ Weekly Youtube Videos

Check it out and subscribe to my channel ↗️ for more Frontend, Leadership and Career Development content.

Stop using v0, try this Instead

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

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Ankita Kulkarni

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