Igor L. — Full-Stack Engineer

Expertise in Full Stack Web, React Native.

Last verified on March, 2026

Core Skills

Bio Summary

Senior JavaScript Engineer with 8+ years of experience; MS in Computer Science and Software Engineering.
Node.js, TypeScript, PostgreSQL, and AWS; High-load projects with JS/TypeScript, Java, QT, and C++.
AWS serverless, Lambda functions (migration architectures, reduced infrastructure costs by 40%, microservices that handle 10K+ concurrent requests with latency less than 200ms); Experience migrating monolithic systems to serverless and microservice architectures, optimizing performance and reducing infrastructure costs (~40%);
Skilled in SDLC practices, including Agile/Scrum, CI/CD pipelines with GitHub Actions and Docker, and pre-test development using Jest and Playwright;

Technical Skills

Programming Languages	C, C++, Java, JavaScript, Sync, TypeScript
JavaScript Frameworks	Angular, Express, Ext JS, NestJS, Node.js, React
Java Libraries and Tools	Apache Velocity, Vert.x
Mobile Frameworks and Libraries	Crashlytics
JavaScript Libraries and Tools	React Native, Redux-Saga
Data Analysis and Visualization Technologies	Presto S3
Databases & Management Systems / ORM	AWS DynamoDB, AWS ElasticSearch, MySQL, PostgreSQL, SQL
UI Frameworks, Libraries, and Browsers	LESS
Cloud Platforms, Services & Computing	AWS
Amazon Web Services	AWS DynamoDB, AWS EC2, AWS ElasticSearch, AWS Lambda, AWS S3, AWS SAM
Industry Domain Experience	Blockchain
Methodologies, Paradigms and Patterns	Agile, microservices, Monolithic, REST, Scrum, SDLC, serverless
SDK / API and Integrations	API, OpenAPI, RESTful API, Swagger
Deployment, CI/CD & Administration	CI/CD
Virtualization, Containers and Orchestration	Docker
QA, Test Automation, Security	e2e testing, Jest, Playwright, QA
Version Control	Git, Github Actions
BlockChain and Decentralized Software	Optimism
Third Party Tools / IDEs / SDK / Services	Qt Framework
Platforms	SAAS
Mail / Network Protocols / Data transfer	WebSockets
Other Technical Skills	Backend, computer science, Core, Load, MS, Performance Optimization, POS, Qt/Qtopia, Software Engineering, Stream

Work Experience

Full-Stack Engineer, Table Booking App

Duration: Sep 2024 -January 2026

Summary: A table booking app for an all-in-one restaurant platform serving 29,000+ restaurants.

Responsibilities and Achievements:

Launched a full-stack React Native + Node.js booking app from zero to production in 12 weeks, onboarding 500+ restaurant locations within the first release cycle and establishing a new revenue stream.
Engineered an event-driven backend architecture that sustained 10K+ concurrent booking requests at sub-200ms p95 latency, eliminating reservation bottlenecks during peak dinner hours;
Eliminated 90% of double-booking incidents by designing a WebSocket-based real-time sync layer between mobile clients and backend reservation services;
Raised unit test coverage from 0% to 85%+ across all new modules by championing a test-first culture and conducting 50+ pull request reviews.

Technologies: React Native, Node.js, TypeScript, RESTful API, WebSockets, Jest, Agile, Scrum.

Full-Stack Engineer, Pharmaceutical supply chain platform

Duration: Sep 2022 - May 2024

Summary: Blockchain-powered pharmaceutical supply chain platform - architecture modernization, and performance optimization.

Responsibilities and Achievements:

Slashed infrastructure costs by ~40% by leading migration from monolithic Node.js to AWS serverless (Lambda, DynamoDB, S3);
Accelerated frontend performance by 57% by re-architecting the Angular app with lazy loading and code splitting, reducing page load from 4.2s to 1.8s with green Core Web Vitals;
Compressed release cycles from 2 days to under 2 hours by designing a CI/CD pipeline with GitHub Actions, Docker, and automated quality gates;
Prevented 30+ production regressions over 6 months by building a Playwright E2E test suite spanning 120+ critical user workflows, reducing QA cycle time by 50%;
Enabled FDA DSCSA compliance by integrating blockchain-based verification APIs, directly unblocking 3 enterprise contracts worth $2M+ in ARR.

Technologies: AWS Lambda, DynamoDB, S3, NestJS, Angular, TypeScript, Docker, GitHub Actions, Playwright.

Node.js Engineer, Educational system

Duration: Jan 2021 - Jan 2022

Summary: Full technical ownership of legacy educational system rewrite to modern TypeScript/Node.js.

Responsibilities and Achievements:

Produced a phased migration roadmap by auditing a 50K+ line legacy codebase, identifying 15 high-risk modules, and presenting risk-mitigation strategies adopted by engineering leadership;
Increased system uptime from ~95% to 99.5% by rewriting core POS modules in TypeScript/Express.js, reducing production incidents by 70%;
Reduced frontend-backend integration defects by 60% by authoring OpenAPI/Swagger specs across 40+ REST endpoints, creating a single source of truth for 3 consuming teams;
Boosted sprint velocity by 25% by establishing code review standards, Git branching strategy, and structured retrospectives - transforming ad-hoc workflow into repeatable Agile delivery.

Technologies: TypeScript, Node.js, Express.js, AWS EC2, Docker, OpenAPI, Swagger, REST APIs.

Full-Stack Developer, Enterprise Workforce Analytics Platform

Duration: Jun 2017 - Jul 2020

Summary: Enterprise workforce analytics - cross-platform desktop agents + web reporting dashboard for HR teams.

Responsibilities and Achievements:

Coordinated delivery across 3 parallel workstreams as technical lead of a 5-person team, hitting 100% of sprint milestones on schedule over a 3-year engagement;
Delivered 10x improvement in report generation speed by building an Angular 6 + Elasticsearch dashboard, replacing a manual Excel workflow and saving managers 15+ hours/week;
Achieved 99.7% data capture accuracy across 1,000+ workstations by developing cross-platform C++/Qt desktop agents with automatic error recovery and offline buffering;
Halved junior developer ramp-up time from 3 months to 6 weeks by creating a structured onboarding program with pair programming rotations and weekly knowledge-sharing sessions.

Technologies: C++, Java, TypeScript, Angular 6, Vert.x, Qt, Elasticsearch, Docker.

Education

Master of Science in Software Engineering
Cherkasy State Technological University
2014 - 2018

How to hire with Upstaff

1

Talk to Our Talent Expert

Our journey starts with a 30-min discovery call to explore your project challenges, technical needs and team diversity.

2

Meet Carefully Matched Talents

Within 1-3 days, we’ll share profiles and connect you with the right talents for your project. Schedule a call to meet engineers in person.

3

Validate Your Choice

Bring new talent on board with a trial period to confirm you hire the right one. There are no termination fees or hidden costs.

Why Upstaff

Upstaff is a technology partner with expertise in AI, Web3, Software, and Data. We help businesses gain competitive edge by optimizing existing systems and utilizing modern technology to fuel business growth.

Real-time project team launch

<24h

Interview First Engineers

Upstaff's network enables clients to access specialists within hours & days, streamlining the hiring process to 24-48 hours, start ASAP.

x10

Faster Talent Acquisition

Upstaff's network & platform enables clients to scale up and down blazing fast. Every hire typically is 10x faster comparing to regular recruitement workflow.

Vetted and Trusted Engineers

100%

Security And Vetting-First

AI tools and expert human reviewers in the vetting process is combined with track record & historically collected feedbacks from clients and teammates.

~50h

Save Time For Deep Vetting

In average, we save over 50 hours of client team to interview candidates for each job position. We are fueled by a passion for tech expertise, drawn from our deep understanding of the industry.

Flexible Engagement Models

Custom Engagement Models

Flexible staffing solutions, accommodating both short-term projects and longer-term engagements, full-time & part-time

Unique Talent Ecosystem

Candidate Staffing Platform stores data about past and present candidates, enables fast work and scalability, providing clients with valuable insights into their talent pipeline.

Transparent

$0

No Hidden Costs

Price quoted is the total price to you. No hidden or unexpected cost for for candidate placement.

x1

One Consolidated Invoice

No matter how many engineers you employ, there is only one monthly consolidated invoice.

Ready to hire Igor L.
or someone with similar Skills?

Book a call with Igor L.

Start Hiring