Marshall Shen, Developer in Chicago, IL, United States
Marshall is available for hire
Hire Marshall

Marshall Shen

Verified Expert  in Engineering

Bio

Marshall is an accomplished technical leader with a strong background in building AI software and leading engineering teams. He has delivered innovative solutions for tech companies of all sizes in fintech and healthcare. With over three years of experience running startups, he has led engineering teams of over 20 people, including offshore teams in China. As a software architect at Venmo, he builds scalable payment systems, mentors engineers, and builds a resilient engineering organization.

Portfolio

Ashleigh Tatiana Aston
Python, React, Web Architecture, Vue, SQL, HTML, Machine Learning, MySQL, CSS...
Reflik Inc
Python, React, MySQL, Software Architecture, Microservices, PHP
Shearwater Health Inc
Databases, REST APIs, APIs, MySQL, Cron, SQL, CSV, JSON, Python, JavaScript...

Experience

Availability

Part-time

Preferred Environment

MacOS

The most amazing...

...thing I've built was a virtual education classroom product that supports more than 100,000 virtual classrooms per day.

Work Experience

Web Full-stack Developer (via Toptal)

2023 - PRESENT
Ashleigh Tatiana Aston
  • Developed a social media platform for digital publishers with OpenAI integration.
  • Migrated the old data from the legacy media site to the new publishing site.
  • Built a full-stack web app from scratch using Ruby on Rails and React/TypeScript deployed on Google Cloud Platform.
Technologies: Python, React, Web Architecture, Vue, SQL, HTML, Machine Learning, MySQL, CSS, JavaScript, Web Development, PyTorch, Non-performing Loans (NPL), Artificial Intelligence (AI), Node.js, Cloud, Cloud Services, API Integration, APIs

Technical Architect (via Toptal)

2023 - 2024
Reflik Inc
  • Led the architecture of Reflik's new AI-based talent marketplace. Built the foundational infrastructure on AWS using Kubernetes, Python Django, and React, with GitHub Actions for the CI/CD pipeline.
  • Trained the development team in India to use the foundational infrastructure.
  • Worked with business leaders to finalize their two-year product roadmap.
Technologies: Python, React, MySQL, Software Architecture, Microservices, PHP

API Developer (via Toptal)

2023 - 2024
Shearwater Health Inc
  • Worked with the executive to refine the data pipeline using Microsoft Power BI and Microsoft Azure.
  • Automated the nurse staffing data pipeline using Ruby on Rails and Microsoft Azure.
  • Trained the staff to be self-sufficient and operate the data pipeline themselves.
Technologies: Databases, REST APIs, APIs, MySQL, Cron, SQL, CSV, JSON, Python, JavaScript, Company Databases

Fractional CTO

2022 - 2024
HiLink
  • Provided technical vision to transition the company to a platform-as-a-service (PaaS) business.
  • Managed a remote engineering team of 12 in China.
  • Helped the company win enterprise customers and secure the first few enterprise contracts, which would help the company secure additional venture capital funding.
Technologies: Java, Management, Team Leadership, React

AWS Architect

2022 - 2023
One Step Holdings LLC
  • Consulted with clients to determine their business needs.
  • Developed software designs using AWS to meet those needs.
  • Created a Python/Docker codebase that lets clients quickly begin product development.
Technologies: Amazon Web Services (AWS), Technical Project Management, AWS Certified Developer, Agile Project Management, Project Management

Senior Developer

2022 - 2023
Therapy App LLC
  • Built expert HIPAA-compliant data pipelines for personal patient data.
  • Served 40+ mental health clinics across the US, providing practical solutions tailored to each client's needs.
  • Delivered requested patient information within tight timelines without sacrificing quality.
Technologies: Java, Spring Boot, PHP, Amazon Web Services (AWS), Laravel, React, Vue, React Native, MongoDB

Senior Software Engineer

2015 - 2017
PatientPoint
  • Launched a new product that managed digital content across 10,000+ IoT devices. Used Ruby on Rails for the back end, Vue.js for the front end, and Postgres DB as data storage.
  • Acted as a tech lead for a team of ten developers and prioritized development tasks with the product and leadership team.
  • Designed RESTful APIs and relational database systems for healthcare content streaming from scratch.
Technologies: Ruby, Vue, Ruby on Rails API, Technical Leadership, PostgreSQL, Software Development, Algorithms, HTML, JavaScript, Chrome Extensions, Ruby on Rails (RoR), Test-driven Development (TDD), APIs, Back-end, Amazon Web Services (AWS), Back-end Development, Git, Heroku, Web Development, REST APIs, Unit Testing, Integration Testing, Software Testing Automation Framework (STAF), User Interface (UI), CSS, OpenAPI, Full-stack, Linux, Enterprise, Enterprise Systems, Software Architecture, Jira, Project Management, Slack, GitFlow, Agile Project Management

Software Engineer

2012 - 2015
Groupon
  • Launched an internal accounting service to help merchant payments and developed payment algorithms that processed more than 1 billion USD of payments.
  • Developed and maintained the Ruby on Rails app with more than 100,000 merchants globally.
  • Worked with the Groupon finance and accounting team to help process and reconcile payments.
Technologies: API Architecture, Amazon Web Services (AWS), Computer Security, Software Development, QuickBooks API, Algorithms, HTML, JavaScript, Ruby on Rails (RoR), Test-driven Development (TDD), APIs, Back-end, Back-end Development, Git, Heroku, Web Development, Java, REST APIs, Spring, Spring Boot, Unit Testing, Integration Testing, Software Testing Automation Framework (STAF), User Interface (UI), CSS, OpenAPI, Full-stack, Linux, Enterprise, Enterprise Systems, Software Architecture, Jira, Project Management, GitFlow, Agile Project Management

HackerPen

HackerPen is an interactive, online peer-to-peer mock interview platform that allows people to practice technical interviews with each other using video or audio chat and collaborative coding and drawing pads, all in one web app.

I created this platform and launched it in April 2022. As of September 2022, the platform is running with 300+ active users.

BuildU

A student engagement application focused on American universities and colleges. The system was built on Ruby on Rails, React and React Native.

I worked as the CTO of the company, and I was in charge of building the application and managing the software development process.
2014 - 2015

Master's Degree in Computer Science

Columbia University - New York, NY, USA

2008 - 2012

Bachelor's Degree in Statistics

University of Iowa - Iowa City, IA, USA

2008 - 2012

Bachelor's Degree in Computer Science

University of Iowa - Iowa City, IA, USA

JULY 2020 - PRESENT

Functional Programming Principles in Scala

Coursera

APRIL 2019 - PRESENT

Deep Learning Specialization

Coursera

OCTOBER 2017 - PRESENT

Interaction Design Specialization

Coursera

Libraries/APIs

Ruby on Rails API, React, REST APIs, Node.js, OpenAPI, Vue, QuickBooks API, PyTorch

Tools

Git, Jira, Slack, Terraform, Google Compute Engine (GCE), Amazon EKS, RabbitMQ, Cron

Languages

Python 3, Java, Ruby, Bash, TypeScript, HTML, JavaScript, Python, CSS, Elixir, PHP, GraphQL, Scala, SQL

Frameworks

Django, Ruby on Rails (RoR), Spring, Spring Boot, Material UI, MUI CSS, Bootstrap, Flutter, React Native, Angular, Laravel

Paradigms

API Architecture, Test-driven Development (TDD), Unit Testing, Agile Project Management, Microservices, Web Architecture, Management

Platforms

Docker, MacOS, Amazon Web Services (AWS), Linux, Google Cloud Platform (GCP), Kubernetes, Firebase, Heroku

Storage

MySQL, PostgreSQL, MongoDB, Google Cloud, Cloud Firestore, Databases, JSON, Company Databases

Industry Expertise

Project Management

Other

Software System Architecture Development, Technical Leadership, Software Development, Algorithms, APIs, Back-end, Back-end Development, Web Development, Integration Testing, Software Testing Automation Framework (STAF), User Interface (UI), Full-stack, ESLint, Enterprise, Enterprise Systems, Software Architecture, GitFlow, Architecture, Computer Science, Amazon RDS, Technical Program Management, Chrome Extensions, Team Leadership, Artificial Intelligence (AI), Computer Security, Statistical Analysis, Statistical Modeling, Interaction Design (IxD), Fintech, CTO, Technical Project Management, AWS Certified Developer, CSV, Machine Learning, Non-performing Loans (NPL), Cloud, Cloud Services, API Integration

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.

1

Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3

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