# Mehedi Hasan Shifat

> Product engineer with AI depth. I build AI products end to end, from multi-agent systems at Nordivo to Pagewala, my live AI sales agent, and make the systems under them fast.

Product Engineer · AI Products & Systems, based in Dhaka, Bangladesh. Open to collaborations.

Every page on this site has a markdown version: add `.md` to its path (`/index.md` for the home page), or request the page with `Accept: text/markdown`. The whole site is one file at https://www.heyshifat.com/llms-full.txt. Agents can also connect to the read-only MCP server at https://www.heyshifat.com/mcp (Streamable HTTP, no auth); setup is at https://www.heyshifat.com/agents.

## Pages

- [Profile](https://www.heyshifat.com/index.md): Mehedi Hasan Shifat is a product engineer building AI products end to end, from multi-agent systems at Nordivo to Pagewala, a live AI sales agent.
- [Projects](https://www.heyshifat.com/projects.md): All 18 things Shifat has built: AI products, everyday tools, developer tools, and apps.
- [Experience](https://www.heyshifat.com/experience.md): Every role Shifat has held, with freelance client work and reviews.
- [Services](https://www.heyshifat.com/services.md): How to work with Shifat: what he offers and who it suits.
- [Logs](https://www.heyshifat.com/blog.md): Every post, newest first: building software, AI systems, and developer tools.
- [Contact](https://www.heyshifat.com/contact.md): How to reach Shifat.

## Case studies

- [Pagewala: an AI sales agent for Facebook Page sellers](https://www.heyshifat.com/projects/pagewala.md): How I built an AI agent that answers customer questions and captures orders through Messenger for small sellers in Bangladesh, without letting it invent a single price.

## Logs

- [Never Let the Model Touch the Price](https://www.heyshifat.com/blog/never-let-the-model-touch-the-price.md): Lessons from building an AI sales agent that takes real orders: the model can suggest, but the server decides, especially when money and stock are involved.
- [Why I Built Exciton](https://www.heyshifat.com/blog/why-i-built-exciton.md): Agentic frameworks for Claude Code install once and govern every session. A three-line bug fix shouldn't get the same ceremony as a new subsystem, so I built a per-session dial.
- [How to Use Claude Code or Codex for Real Coding Work](https://www.heyshifat.com/blog/how-to-use-claude-code-or-codex-for-real-coding-work.md): A practical Claude Code and Codex workflow for software engineers: discuss the idea first, lock the implementation plan, break work into epics, ship task by task, and write strong unit tests.
- [Context Engineering Beats Clever Prompts](https://www.heyshifat.com/blog/context-engineering-beats-clever-prompts.md): In the current AI era, model quality depends less on clever wording and more on the context you assemble around the task.
- [Shipping Software in the Agent Era](https://www.heyshifat.com/blog/shipping-software-in-the-agent-era.md): AI agents did not remove engineering work. They shifted the bottleneck from typing code to defining scope, guardrails, and review loops.
- [Why AI Products Need an Evaluation Layer](https://www.heyshifat.com/blog/why-ai-products-need-an-evaluation-layer.md): If your product depends on model output, you need more than anecdotes and vibes. You need evals that tell you when quality is improving or regressing.
- [Claude Code Changed How I Build Software](https://www.heyshifat.com/blog/claude-code-changed-how-i-build.md): I stopped using AI as autocomplete and started using it as an implementation partner. Here's how Claude Code reshaped my entire development workflow.
- [TypeScript Patterns I Actually Use](https://www.heyshifat.com/blog/typescript-patterns-i-actually-use.md): Not the advanced wizardry — just the practical patterns that show up in real codebases and make the type system work for you.

## Optional

- [Uses](https://www.heyshifat.com/uses.md): The tools, stack, and setup he reaches for day to day.
- [Resume](https://www.heyshifat.com/mehedi_hasan_shifat_resume.pdf): PDF