Christopher Lam - Software Engineer

Q: Where is Christopher based?

Christopher is based in Warsaw, Poland .

Q: What languages does Christopher speak?

Christopher speaks the following languages: English (Advanced), Vietnamese (Intermediate) .

Q: How many years of experience does Christopher have?

Christopher has at least 9 years of experience. During this time, Christopher has worked in at least 4 different roles and for 4 different companies . The average length of individual experience is 2 years and 2 months . Note that Christopher may not have shared all experience and actually has more experience.

Q: What is Christopher's latest experience?

Christopher's most recent position is Software Engineer at Opencast .

Q: What companies has Christopher worked for in recent years?

In recent years, Christopher has worked for Opencast , VentureCraft , and Axeos .

Q: Which industries is Christopher most experienced in?

Christopher is most experienced in industries like Information Technology (IT) and Retail .

Q: Which business areas is Christopher most experienced in?

Christopher is most experienced in business areas like Information Technology (IT) , Product Development , and Project Management . Christopher also has some experience in Business Intelligence .

Q: Which industries has Christopher worked in recently?

Christopher has recently worked in industries like Information Technology (IT) and Retail .

Q: Which business areas has Christopher worked in recently?

Christopher has recently worked in business areas like Information Technology (IT) , Product Development , and Project Management .

Recommended expert

Warsaw, Poland

Experience

Apr 2024 - Present

1 year 11 months

Software Engineer

Opencast

Designed and implemented scalable Ruby on Rails microservices to handle 10,000+ concurrent users with 99.9% uptime.
Developed a cloud-based analytics dashboard integrating PostgreSQL and Redis, reducing data retrieval time by 35%.
Spearheaded front-end migration from legacy JS to React.js, enhancing application responsiveness and user retention.
Architected RESTful APIs with secure OAuth2 authentication, increasing integration efficiency with third-party services by 40%.
Implemented CI/CD pipelines using GitHub Actions, cutting deployment time by 50% and ensuring zero downtime releases.
optimized SQL queries and indexes for high-volume transaction processing, improving database performance by 30%.
Led a team of 3 engineers in agile sprints, managing project backlog and delivering features ahead of deadlines.
Designed and executed unit and integration tests using RSpec and Capybara, achieving 95% code coverage.
Integrated AWS S3 storage for file uploads with automatic image optimization, reducing storage costs by 20%.
Developed feature toggle system allowing safe rollouts and A/B testing for critical product features.
Collaborated with UX/UI designers to revamp application interface, resulting in a 25% increase in user engagement.
Real-time Monitoring Platform: Built a Rails backend with WebSocket integration for live notifications and analytics.
Subscription Management System: End-to-end delivery of subscription billing, automated email alerts, and secure payment gateway integration.

Jun 2022 - Mar 2024

1 year 10 months

Full Stack Engineer

VentureCraft

Developed full-stack web applications using Ruby on Rails and React.js, serving 50,000+ monthly active users.
Implemented PostgreSQL and Redis caching strategies, reducing page load times by 40%.
Built GraphQL API endpoints for efficient data fetching and front-end integration.
Deployed containerized applications on AWS EC2 with Docker, ensuring environment consistency across dev, staging, and production.
Automated deployment pipelines with Jenkins, reducing manual errors and accelerating release cycles.
Refactored legacy Rails codebase, improving maintainability and decreasing technical debt by 35%.
Designed and executed unit, integration, and E2E tests, achieving high reliability for production releases.
Integrated third-party APIs for payment processing, messaging, and geolocation services.
Collaborated with cross-functional teams to implement feature-rich e-commerce modules, increasing revenue by 18%.
Conducted performance profiling and implemented caching strategies, increasing application throughput by 50%.
Mentored junior developers, leading code reviews and knowledge-sharing sessions to promote best practices.
E-commerce Platform Revamp: Led full-stack redevelopment including Rails API, React front-end, and PostgreSQL integration.
Analytics & Reporting Module: Designed dynamic dashboards and reporting tools for stakeholders, enabling data-driven business decisions.

Apr 2019 - Dec 2021

2 years 9 months

Full Stack Developer

Axeos

Developed robust web applications using Ruby on Rails, React.js, and PostgreSQL, supporting enterprise clients.
Built modular front-end components and reusable UI libraries to enhance development efficiency.
Implemented RESTful APIs and integrated with internal and external systems.
Optimized database queries and designed indexing strategies, improving response times by 25%.
Collaborated with QA teams to implement automated testing frameworks using RSpec.
Maintained CI/CD pipelines for seamless code deployment.
Assisted in designing microservices for scalable backend architecture.
Refactored legacy applications, reducing maintenance costs and improving code readability.
Integrated third-party APIs for payment, geolocation, and email automation.
Participated in agile sprint planning and backlog refinement.
Inventory Management System: End-to-end delivery of real-time inventory tracking with reporting dashboards.
Client Portal: Developed secure Rails-based portal with multi-role access controls and API integrations.

Jan 2017 - Mar 2019

2 years 3 months

Junior Full Stack Developer

Savvycomp

Assisted in developing full-stack applications with Ruby on Rails and JavaScript frameworks.
Created dynamic web pages and reusable front-end components using HTML, CSS, and jQuery.
Built and maintained RESTful APIs for internal and external integrations.
Optimized SQL queries for small-to-medium database applications.
Participated in code reviews and learned agile development practices.
Collaborated with senior developers to implement new modules and features.
Assisted in front-end UX improvements based on user feedback.

Industries Experience

See where this freelancer has spent most of their professional time. Longer bars indicate deeper hands-on experience, while shorter ones reflect targeted or project-based work.

Experienced in Information Technology (8.5 years) and Retail (2 years).

Information Technology

Retail

Business Areas Experience

The graph below provides a cumulative view of the freelancer's experience across multiple business areas, calculated from completed and active engagements. It highlights the areas where the freelancer has most frequently contributed to planning, execution, and delivery of business outcomes.

Experienced in Information Technology (8.5 years), Product Development (8.5 years), Project Management (2 years), and Business Intelligence (2 years).

Information Technology

Product Development

Project Management

Business Intelligence

Summary

Highly skilled Senior Full Stack Engineer with 7+ years of experience designing, developing, and deploying scalable web applications. Expertise in Ruby on Rails, JavaScript frameworks, PostgreSQL, and cloud-based architecture. Proven ability to deliver end-to-end solutions, optimize performance, and enhance user experiences. Adept at leading cross-functional teams, implementing CI/CD pipelines, and driving measurable results through data-driven decision-making.

Skills

Languages & Frameworks: Ruby On Rails, Javascript (Es6+), React.js, Node.js, Html5, Tailwindcss, Jquery
Databases: Postgresql, Mysql, Mongodb, Redis
Cloud & Devops: Aws (Ec2, S3, Lambda), Docker, Kubernetes, Ci/cd, Github Actions, Jenkins
Tools & Platforms: Git, Jira, Trello, Vscode, Postman, Rspec, Capybara
Api & Integration: Restful Apis, Graphql, Third-party Api Integration
Development Practices: Agile/scrum, Tdd/bdd, Microservices, Continuous Integration & Deployment (Ci/cd)
Performance & Optimization: Sql Query Optimization, Caching Strategies, Load Balancing
Testing & Quality Assurance: Unit Testing, Integration Testing, End-to-end (E2e) Testing, Automated Testing

Languages

English

Advanced

Vietnamese

Intermediate

Education

Sep 2012 - Jun 2016

Ton Duc Thang University

Bachelor of Science, Computer Science · Computer Science · Ho Chi Minh City, Viet Nam

Profile

Created

November 2025

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Frequently asked questions

Do you have questions? Here you can find further information.

Where is Christopher based?

Christopher is based in Warsaw, Poland.

What languages does Christopher speak?

Christopher speaks the following languages: English (Advanced), Vietnamese (Intermediate).

How many years of experience does Christopher have?

Christopher has at least 9 years of experience. During this time, Christopher has worked in at least 4 different roles and for 4 different companies. The average length of individual experience is 2 years and 2 months. Note that Christopher may not have shared all experience and actually has more experience.

What roles would Christopher be best suited for?

Based on recent experience, Christopher would be well-suited for roles such as: Software Engineer, Full Stack Engineer, Full Stack Developer.

What is Christopher's latest experience?

Christopher's most recent position is Software Engineer at Opencast.

What companies has Christopher worked for in recent years?

In recent years, Christopher has worked for Opencast, VentureCraft, and Axeos.

Which industries is Christopher most experienced in?

Christopher is most experienced in industries like Information Technology (IT) and Retail.

Which business areas is Christopher most experienced in?

Christopher is most experienced in business areas like Information Technology (IT), Product Development, and Project Management. Christopher also has some experience in Business Intelligence.

Which industries has Christopher worked in recently?

Christopher has recently worked in industries like Information Technology (IT) and Retail.

Which business areas has Christopher worked in recently?

Christopher has recently worked in business areas like Information Technology (IT), Product Development, and Project Management.

What is Christopher's education?

Christopher holds a Bachelor in Computer Science from Ton Duc Thang University.

What is the availability of Christopher?

Christopher is immediately available full-time for suitable projects.

What is the rate of Christopher?

Christopher's rate depends on the specific project requirements. Please use the Meet button on the profile to schedule a meeting and discuss the details.