Justin Klein
Currently @ Bulloch Technologies

Hey, it's Justin.

Full-stack software engineer Β· Toronto πŸ‡¨πŸ‡¦

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A full-stack foundation β€” now going deep on systems-level C++.

The path that got me hereΒ πŸ‘‡

Bulloch Technologies Logo

Jun 2026 - Present

Software Engineer

Bulloch Technologies| Mississauga, ON

C++
Multi-Threading
AI
  • Leveraging multi-threaded C++ to deliver features and resolve bugs on a forecourt petroleum POS system.

  • Responsible for ensuring compliance with third party back-office protocols, loyalty connections, accurate shift reporting and data management within the POS.

  • Working closely with QA to replicate and resolve client-facing software issues.

Author's note

I wanted to embrace the complexity and efficiency of C++. This role gives me autonomy with lots of inter-team communication, which I love.

Data Annotation Logo

Apr 2024 - Jun 2026

Software Developer

Data Annotation| Remote

React
TypeScript
Postgres
Docker
AI
  • Contributed to several long-term AI projects that improved frontier AI models' ability to generate production-ready code.

  • Analyzed and improved LLM code-generation reliability through Reinforcement Learning from Human Feedback (RLHF).

Author's note

This opportunity taught me how to best leverage AI for engineering.

Adknown Logo

Jan 2023 - Aug 2023

Software Developer

Adknown| Guelph, ON

React
PHP
MySQL
AWS
Docker
  • Delivered production features on an web application that interfaced with 3rd party ad services (Google, Bing, Meta) used daily by digital markers.

  • Dockerized two previously untestable ad-tracking pixels.

  • Architected a Bing campaign linkage tool, improving marketers' CPC performance.

Author's note

Everyone on the team was a former Co-op, I was given tangible responsibility and shipped impactful features.

Tulip Retail Logo

May 2022 - Aug 2022

Software Developer

Tulip Retail| Kitchener, ON

React
PHP
MySQL
Docker
  • Delivered features on the LiveConnect & Appointments component of Tulip Retail's POS platform.

  • Contributed to the Tulip Appointments NPM package used by clients such as Chanel and Michael Kors.

  • Integrated the appointments widget into the core Clienteling product, improving high-value customer booking flows.

Author's note

Mid-growth startup, with a product hyper-focused on user experience.

NCR Corporation Logo

Sep 2021 - Dec 2021

Software Developer

NCR Corporation| Waterloo, ON

React
Spring
Docker
  • Worked on the API Toolkit (Draft) team, facilitating the creation of legacy banking API queries through a cutting edge web app.

  • Collaborated in an agile environment, completing JIRA sprint work with high delivery velocity.

Author's note

My manager thanked me for bringing the team out of a peak-lockdown slump with my outgoing personality.

Heart & Stroke Logo

May 2021 - Aug 2021

Web Developer

Heart & Stroke| Toronto, ON

React
Node.js
MySQL
  • Architected a standalone direct-mail donation platform, decoupling a high-fee no code legacy solution.

  • Integrated Stripe and Moneris SDKs, improving PCI compliance and reducing transaction fees by 20%.

Author's note

My first Co-op, at the end of the term I was showcasing the solution to the CFO.

University of Guelph Logo

2019 - 2024

Bachelor of Computing, Honours Software Engineering (Co-op)

University of Guelph| Guelph, ON

C
Python
Java
JavaScript
PHP
SQL
  • Intensive focus on software design, algorithms, data structures, and full stack development.

  • My Capstone was a term-long SDLC full-stack games repository, leveraging React, PHP, Docker, MySQL and CI/CD pipelines.

  • Minor in Business Administration, graduated with Honours (GPA: 84.6%).

Author's note

Computing at Guelph was modern development built upon a legacy foundation. It was real coding assignments over theoretical exams.

Nov 2025 - Present

Get Smart!
TypeScript
Markdown
AWS
GitHub Actions

Astro markdown documentation site hosting a wide range of professional technical notes on software development. Whenever I teach myself a new framework or concept, my notes go here. These notes are also vectorized and uploaded to an AWS S3 Vectors bucket.

Author's note

I believe that learning is a life long journey, and I keep myself accountable by documenting my learning here.

Jan 2026 - Present

Get Quizzed!
React
TypeScript
Next.js
AWS
GitHub Actions

A web app that ingests my vectorized's tech notes + resume and mocks technical interviews based on what I learned. Backend uses an AWS Lambda function and MongoDB backend, plugged in to my Terraform infra, the project is less than $1/month in cloud computing costs.

Author's note

I have a bad habit of just internalizing knowledge, but never communicating it. This tool aims to fix that.

Dec 2025 - Present

AWS Terraform Infrastructure
Terraform
AWS
GitHub Actions

Infrastructure as Code (IaC) project using Terraform to provision and manage AWS resources for personal projects.

Author's note

When an idea strikes, I wanted the infra ready to go to deploy it securely, easily cheaply.

Dec 2025 - Present

Portfolio - this site!
React
TypeScript
Next.js
AWS
GitHub Actions

Personal portfolio website to showcase projects and experience.

Author's note

Resumes alone don't tell your full story, I'm hoping this site makes you curious to dive deeper in person!

Anomet Web CRM Logo

Dec 2025 - Jun 2026

Anomet Web CRM
React
NestJS
Postgres
Azure
Microsoft 365

Led a digital transformation project for a manufacturing SMB β€” architecting a custom web CRM with SharePoint integration, hosted in Azure. The solution let the company work remotely and sunset a legacy Windows server.

Author's note

I owned the product end-to-end and decided every architectural decision.

That's the path so far

Let's build what's next.

Always up for a good problem, a new team, or just a chat about software and the people behind it.