Mark Isayan, Developer in Toronto, ON, Canada
Mark is available for hire
Hire Mark

Mark Isayan

Verified Expert  in Engineering

Full-stack Developer

Toronto, ON, Canada
Toptal Member Since
November 3, 2019

Along with a bachelor’s degree in applied mathematics and computer science, Mark has years of experience in app development for various industries, including medicine, aviation, and business. Mark’s in-depth technical knowledge and skills cover a range of technologies such as blockchain, server/client-side development, quality assurance, database design and development, and server management.


Button Inc.
JavaScript, Node.js, React, GraphQL, PostgreSQL, PostGraphile...
Pondera Services LLC
Node.js, Puppeteer, Amazon Web Services (AWS), Test-driven Development (TDD)...
Python 3, React, Back-end




Preferred Environment

WebStorm, Git, Linux

The most amazing...

...I've built is a decentralized staff management system for internal educational processes capable of handling tens of thousands of transactions per second.

Work Experience

Full-stack Developer

2022 - 2023
Button Inc.
  • Participated in a government project, effectively functioning within a cross-functional team of developers, designers, product owners, and an engineering manager.
  • Utilized React for front-end website development, contributing significantly to user interface enhancement and usability.
  • Participated actively in scope identification for a subproject, aiding in establishing project deliverables and milestones.
  • Applied performance testing, ensuring the website maintained optimal load-bearing capacities and efficient performance.
  • Assisted in planning changes to optimize search engine optimization (SEO) for a pre-existing website, enhancing visibility and traffic.
  • Conducted extensive research on tools to enhance the efficiency of internal systems, leading to significant productivity gains.
  • Contributed to the company's side projects, notably creating a React component library to streamline future front-end development tasks.
  • Integrated behavior-driven development (BDD) with Gherkin language into user stories, promoting an understanding of the system's behavior from the user's perspective.
  • Participated in workshops to understand customer personas and the minimum viable product (MVP) feature set.
Technologies: JavaScript, Node.js, React, GraphQL, PostgreSQL, PostGraphile, Search Engine Optimization (SEO), Apache JMeter

Node.js Developer

2022 - 2022
Pondera Services LLC
  • Developed a Node.js/TypeScript application using Puppeteer, automating form-filling tasks and bypassing the lack of APIs for clients' HTML forms.
  • Integrated AI voice assistant text-to-speech platform by leveraging their API, effectively streamlining customer support call handling and reducing response times for overflowing call center inquiries.
  • Deployed the application on AWS using ECS, Fargate, and Docker containers, ensuring scalable and efficient infrastructure management.
  • Implemented custom deployment scripts, streamlining the deployment process and reducing manual intervention.
  • Employed clean architecture principles, domain-driven design (DDD), and event storming to understand clients' domains, resulting in a tailored solution that addressed their needs.
  • Utilized Jest and test-driven development (TDD) for comprehensive unit testing, ensuring highly testable code by clearly separating entities, business logic, and implementation details.
Technologies: Node.js, Puppeteer, Amazon Web Services (AWS), Test-driven Development (TDD), Domain-driven Design (DDD), TypeScript, Artificial Intelligence (AI), Amazon Elastic Container Service (Amazon ECS), AWS Fargate, Docker, Web Scraping, Text to Speech (TTS)

Full-stack Developer

2021 - 2022
  • Implemented functionality using Python and increased ad revenue by 15%.
  • Tracked and fixed bugs using Jira as a reporting tool.
  • Increased ad targeting by implementing features on the front end using React.
Technologies: Python 3, React, Back-end

Back-end Developer

2021 - 2021
The Brain Train
  • Implemented automatic patient invoicing by utilizing Xero API.
  • Integrated Stripe for automatically charging the patients for appointments.
  • Created logic with Node.js by following DDD guidelines.
  • Simplified accountants' work by offloading part of repetitive work onto a cron job and generating PDF reports every week.
  • Containerized the application for ease of development and deployment.
  • Used Google Cloud services for deploying the application, storing data, and running cron jobs.
Technologies: Xero API, JavaScript, Domain-driven Design (DDD), Cron, Google Cloud, Stripe, Docker, Back-end, REST APIs, Node.js, Git, ECMAScript (ES6), Software Architecture, Google Cloud Platform (GCP), PDF

Back-end Developer

2020 - 2021
  • Integrated payment systems to improve the subscription flow, drastically increasing the number of subscriptions to the application and website.
  • Tracked and fixed bugs using Jira as a reporting tool.
  • Worked on breaking up the monolith architecture into a microservice-based architecture.
Technologies: NestJS, JavaScript, Node.js, Back-end, REST APIs, Linux, Git, NoSQL, ECMAScript (ES6)

Full-stack Developer

2020 - 2020
  • Worked on building an eCommerce from scratch that allowed users to buy puppies from breeders, which led to a successful launch with hundreds of users and counting.
  • Used DDD guidelines and graph theory finite automata to describe, plan out, and eliminate the most probable risk factors from an unorthodox product purchase flow that required complex interactions between multiple parties to complete the purchase.
  • Implemented required back-end logic with Node.js and GraphQL, including payment processor integration, user information management, order placement, and checkout.
  • Brought to life designs provided by the product designer using Next.js and React and integrated them with GraphQL on the back-end.
Technologies: MySQL, Domain-driven Design (DDD), eCommerce, Next.js, React, GraphQL, Node.js, Back-end, Full-stack, HTML5, CSS, Front-end, Git, SQL, ECMAScript (ES6), HTML

Full-stack Developer

2017 - 2019
  • Drastically improved security by fixing various critical issues so that sensitive flight data was inaccessible to unauthorized users.
  • Designed and implemented a CouchDB database and added MapReduce-based views for handling large amounts of aircraft-related data.
  • Added back- and front-end functionality with Node.js and Aurelia according to UML diagrams, making aircraft repair operations easier for staff.
  • Implemented unit and integration tests by utilizing Mocha and Chai to prevent unexpected data loss.
  • Created CRON scripts such as Bash and Node.js for sending aircraft repair notifications to the appropriate users, requesting new flight data from the external APIs and processing it accordingly, and more.
  • Wrote functionality that generated PDF reports about the issues with the aircraft.
Technologies: CouchDB, Aurelia, Node.js, Back-end, Full-stack, HTML5, CSS, REST APIs, Front-end, Linux, Git, ECMAScript (ES6), Software Architecture, HTML, PDF

Back-end Developer

2017 - 2017
Task Pigeon
  • Designed an optimized database architecture from scratch with MongoDB, tailored under task management platform specifications.
  • Created and implemented a migration tool for moving data from an SQL-based database (MySQL) to a NoSQL-based database (MongoDB) for an application version update.
  • Developed the server-side application with Node.js and implemented new task/user management features. Integrated different platforms such as Google Drive, Dropbox, Google Docs, and Slack while following MVC software design pattern guidelines.
  • Set up and maintained a Linux-based server on AWS for hosting the server-side application.
  • Implemented a WebSockets communication protocol-based live collaboration system, making it easier for users to update and view the tasks without refreshing the page.
Technologies: MongoDB, Node.js, Back-end, REST APIs, Linux, Git, SQL, NoSQL, ECMAScript (ES6), Amazon Web Services (AWS)

Back-end Developer

2016 - 2017
  • Redesigned an existing database structure with SQL Server, which dramatically improved the training data request/response speed.
  • Developed an algorithm for finding efficient paths to learn a new technology or skill in the shortest possible time.
  • Created a back-end application with ASP.NET MVC, which allowed people entering the IT industry to develop their careers with ease.
  • Wrote a machine learning algorithm that allowed HR departments to find the fittest candidates for a specific job.
Technologies: Microsoft SQL Server, C#, Back-end, REST APIs, Git, SQL, Azure

Full-stack Developer

2016 - 2016
  • Planned and developed an innovative solution for digital game distribution with Node.js, PostgreSQL, and Angular.
  • Positioned the product in the market by digital advertising and pitching to a large number of investors.
  • Set up and maintained a Linux-based server on Azure.
  • Composed CRON scripts with Bash for task automation.
  • Implemented a scalable RESTful API architecture with Node.js that could handle high amounts of product-order-related data flow.
  • Created unit/integration tests with Mocha and Chai to increase the application's stability.
Technologies: PostgreSQL, Angular, Node.js, Back-end, Full-stack, HTML5, CSS, REST APIs, Front-end, Linux, Git, SQL, ECMAScript (ES6), Azure, HTML

Software Developer Intern

2012 - 2012
Avery Dennison
  • Increased medical product manufacturing efficiency by decreasing the amount of time needed for fixing faulty equipment.
  • Integrated a legacy issue tracking system with a newly created solution with VB.NET and provided backward compatibility.
  • Developed a data-locking mechanism on an open database that gave permission to view data to only authorized users.
Technologies: Microsoft Access, VB.NET

Turing Machine Simulator
I developed a command-line application that receives a command set and simulates its execution on a Turing machine. Some mathematical models can be hard to understand. This application aims to help people get a more intuitive understanding of the essence of one of the most important abstract machines in the automata theory. The application uses the Windows API to animate the work of the Turing machine directly in the CLI.

8086 Assembly Emulator
I built a tool that emulates the execution of 8086 assembly instructions. Written in pure JavaScript, this application helped me and many other people visualize the work of the Intel 8086 microprocessor to understand the impact each instruction has on the computer's inner workings. It tracks the state of the memory and registers, which can be dumped for further inspection.

Chrome Extension | ASCII Emojis for

A Chrome extension that adds an ability to select ASCII emoji from a list provided by the extension, which inserted it directly into chat's input box. The list was scraped from a website since the owner couldn't provide me with an API, so he gave me permission.

Chrome Extension for YouTube

A Chrome extension for YouTube which I wrote for myself after noticing that YouTube lacks certain functionality like showing the like/dislike bar in the search results page, hiding it on the watch page, hiding comments based on keywords specified (to hide spoilers, for example), hiding unrelated recommended videos on the watch page based on the result of the analysis of video title.

Student Data Analytics System
Built from scratch and using a cutting-edge permission distributed ledger framework, this application allows universities to manage and analyze their staff and students' performance. Lecturers also can track a student's academic progress. On top of that, since this information is public, employers can check if an employee's diploma is valid.

Camping Security System

A hobby project of mine, which consists of two security measure devices specifically designed to deter people from stealing from tents when there is no one inside. One of the devices is placed inside a tent, which detects human presence using IR and microwave radar detectors and sends a signal to the second device—a receiver that notifies you if someone has entered your tent. Communication is done using LoRa technology, which allows both devices to communicate at large distances using minimal current.

Created a charade game from scratch. The development included making animations, interacting with Firebase for data storage, integrating third-party services for ads, bug tracking, and data analytics.

Technologies: React Native (Expo), Animated library, i18n, AdMob, Firebase, and Sentry.
2015 - 2019

Bachelor's Degree in Applied Mathematics and Computer Science

Russian-Armenian University - Yerevan, Armenia


Linux LE-1

Linux Professional Institute


REST APIs, Node.js, React, Windows API, Xero API, Stripe, Puppeteer, Twitter API


Git, WebStorm, Microsoft Access, Expo, Cron, Amazon Elastic Container Service (Amazon ECS), AWS Fargate, Telegraf, Apache JMeter


JavaScript, HTML, HTML5, CSS, ECMAScript (ES6), SQL, TypeScript, VB.NET, Embedded C++, GraphQL, C#, C++, Assembly, Python 3


Angular, Aurelia, NestJS, Next.js, React Native


Test-driven Development (TDD), Search Engine Optimization (SEO)


Hyperledger Fabric, Linux, Azure, Arduino, Amazon Web Services (AWS), Docker, Google Cloud Platform (GCP), Blockchain


NoSQL, MongoDB, CouchDB, PostgreSQL, Microsoft SQL Server, MySQL, Google Cloud


Full-stack, Back-end, Domain-driven Design (DDD), Software Architecture, Front-end, Chrome Extensions, PDF, Electronics, Web Scraping, Computer Science, PCB Design, eCommerce, Artificial Intelligence (AI), Text to Speech (TTS), Bots, Telegram Bots, PostGraphile

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.


Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring