Infrastructure Engineering Senior Advisor, Evernorth (Cigna)

Ronit Dahiya

Full-stack developer building an enterprise AI chatbot with custom MCP tooling, and the automation behind Cigna's private cloud.

See the work Contact

When something is hard to understand, I build a version I can watch.

That is how I learned system design in college, and how I work today: automate the repetitive, visualize the invisible, and own things end to end.

Selected work

Real product, real footage. The last one runs a live simulation right on this page.

The real product: architectures built, simulated, and stress-tested live.

System Design Simulator

System design would not click for me in college: the diagrams stayed static and the words stayed abstract. So I built a simulator where architectures actually run.

Live at syssimulator.com: put a design under load, inject chaos, and watch queues grow, latency climb, and cost respond.

Event-driven simulation engine with async state propagation across service graphs, compiled to WebAssembly.

  • Rust
  • WebAssembly
  • Flutter Web

syssimulator.com private repo

The real bot, mid-follow.

LuggageBot

A ROS robot that detects and follows a person (or a cylinder) in real time, using image segmentation with Mask R-CNN.

Built in the pre-GPT era: giving a robot eyes still meant wiring the vision pipeline yourself.

  • Python
  • ROS
  • Mask R-CNN
  • OpenCV

GitHub

Estimation with the team, teddy included.

Poker Planning

Mid-COVID, every free estimation tool locked the team out after two weeks. So I built ours: shared sessions, live votes, synchronized reveals, and a Rive teddy reacting to every move.

  • React
  • Django
  • WebSockets
  • Rive

Live app GitHub

Gameplay: navigate the maze, collect power-ups, and outrun the ghosts.

Pixel Pals

A Pygame arcade game: guide your pal through obstacles, grab coins and power-ups, and stay ahead of enemies that hunt with breadth-first search.

  • Python
  • Pygame
  • BFS

Play live GitHub

Experience

Seven years, one direction.

  1. Infrastructure Engineering Senior AdvisorEvernorth (Cigna)

    Jul 2025 to present, Galway

    Own the UnITy AI chatbot for Cigna's private cloud end to end: cut LLM spend by optimizing token usage across summarization, context, and tool calls; shipped MCP integrations on FastMCP; hardened security by leading SAST/SCA remediation; raised release confidence with Playwright automation across UnITy and CloudBolt.

  2. Software EngineerEricsson

    Jul 2023 to Jul 2025, Athlone

    Ericsson Key Contributor Award

    Cut deployment time and maintenance cost by migrating the Software Provisioning Tool from PHP to Django; automated vApp deployments and Jenkins workflows; drove the VMware licensing reduction that earned a company Key Contributor award.

  3. Graduate Software DeveloperEricsson

    Jul 2022 to Jul 2023, Athlone

    Backend development and CI tooling in Python, Java, Docker, and Kubernetes. Led tool transfers between teams and built internal tools on Node, AngularJS, and MongoDB.

  4. Software Engineer InternEricsson

    Mar 2021 to Jul 2022, Athlone

    Lifted tool usage 40% by redesigning search across internal engineering tools, raised team productivity ~25% with new tooling and features, and modernized Java services to Java 11.

Education

BSc (Hons) Computer Science with Data Science

University College Dublin

2018 to 2022, Dublin

First Class Honours

Data science and statistics on top of core CS: networks, information security, software engineering, and large-scale data handling in Python, R, Java, and SQL.

Technology Lead

Google Developer Student Clubs, UCD

Sep 2021 to May 2022, Dublin

Led UCD's student developer community: taught Android, Google Cloud, and machine learning, and grew active membership by 30% in the club's first year.

Toolbox

Languages

  • Python
  • Java
  • JavaScript
  • Rust
  • C++
  • SQL

Frameworks

  • Django
  • Node.js
  • React
  • AngularJS
  • Flutter

Cloud & platform

  • Docker
  • Kubernetes
  • OpenStack
  • VMware
  • CloudBolt
  • Jenkins
  • CI/CD

AI & testing

  • MCP
  • FastMCP
  • LLM cost optimization
  • Playwright
  • Selenium
  • Locust

How I work

  • Automate the boring parts.
  • If you can't see it, you can't fix it.
  • Own things end to end.