Viktor is available for hire

Viktor Lototskyi

Verified Expert in Engineering

APIs Developer

Toronto, ON, Canada

Toptal member since December 17, 2012

Expertise

Full-stack Debugging Web Development Front End API Back-end Developers Integration SaaS Dashboard PayPal Development

Bio

Viktor is a senior/principal software engineer with 20+ years of production experience across web platforms, gaming, and complex systems. He combines strong architectural judgment with hands-on execution and is known for owning problems end-to-end. Viktor works effectively in ambiguous environments, aligning technical decisions with real business goals while collaborating closely with both technical and non-technical stakeholders.

Portfolio

Hard Rock Digital

Agentic AI, JavaScript, Node.js, React, Technical Leadership, API Architecture...

Hard Rock Digital

JavaScript, TypeScript, Node.js, React, Next.js, Architecture, API Architecture...

Ignition

JavaScript, TypeScript, Ruby, PostgreSQL, APIs, HTML5, React...

Experience

APIs - 18 years
JavaScript - 18 years
jQuery - 14 years
PHP - 14 years
TypeScript - 7 years
React - 7 years
Laravel - 6 years
Node.js - 4 years

Preferred Environment

Linux, Windows, Visual Studio Code (VS Code), AI Tools, Agile, Amazon Web Services (AWS)

The most amazing...

...thing I built from scratch was GeneFood, a production platform that processes genomic data to generate personalized health reports for real users.

Work Experience

Lead HTML5 Game Developer

2026 - PRESENT

Hard Rock Digital

Built a new 0-to-1 AI-enabled HTML5 game framework for real-money slot games.
Led the technical delivery of new HTML5 slot games from architecture through QA, certification, and production readiness.
Guided framework architecture, reusable systems, and integration patterns across multiple titles.
Led and supported a team of HTML5 game developers through planning, implementation, and delivery.
Coordinated across product, design, QA, platform, and external provider teams.
Improved team workflows through better documentation, tooling, technical planning, and early risk identification.
Helped establish AI-assisted development practices that improve speed while keeping architecture and quality controlled.

Technologies: Agentic AI, JavaScript, Node.js, React, Technical Leadership, API Architecture, Software Architecture

Senior Game Developer

2024 - PRESENT

Hard Rock Digital

Designed and developed an HTML5 game framework from scratch, establishing the technical foundation for real-money casino games.
Led development of multiple real-money games from prototype to production, supporting launches across regulated jurisdictions.
Collaborated closely with back-end, QA, DevOps, and platform teams to integrate games with 3rd-party RGS providers.
Introduced local development tooling, workflows, and automation to improve developer productivity and delivery reliability.
Played a key role in scaling the client engineering team by hiring, mentoring, and supporting senior developers.
Acted as a technical lead across cross-team initiatives, aligning architecture and execution for complex, multi-team projects.

Technologies: JavaScript, TypeScript, Node.js, React, Next.js, Architecture, API Architecture, Databases, Web Development, Game Development, AI Agents, Claude, Agentic AI, Cursor AI, Back-end Development, API Testing, API Design, CSS, Front-end Development, Vibe Coding, AI Integration, Search Engine Optimization (SEO), QR Codes, Apple Pay, Best Practices, Problem Solving, Claude Code, Test-driven Deployment, AI Programming, AI Design, AI-generated Code, Automation, Web App Development, Mobile First, Vercel, WebGL, Figma to React, Security, Reliability, Twilio, SMS, Scheduling, Message Queues, Queuing Systems, Task Scheduling, Real-time Systems, Real-time Data, Large Language Models (LLMs)

Lead Developer

2022 - 2024

Ignition

Led and grew a distributed engineering team, establishing a culture of ownership, candid feedback, and peer accountability that improved delivery consistency.
Delivered high-impact product improvements as a senior individual contributor while acting as a technical liaison across product, design, and engineering teams.
Partnered with engineering leadership to refine development processes, tooling, career frameworks, and OKRs, strengthening alignment across teams.
Influenced key architectural and infrastructure decisions supporting the product roadmap, scalability goals, and long-term platform evolution.

Technologies: JavaScript, TypeScript, Ruby, PostgreSQL, APIs, HTML5, React, Agile Software Development, Stripe API, CSS3, Class-based OOP, Adobe Photoshop, Prototyping, React Redux, Chakra UI, GraphQL, React Apollo, Storybook, Apache, Unit Testing, Jest, Google Analytics, Web Development, REST, Stripe, Back-end, Web Applications, API Integration, PostgreSQL 9, JSON, SaaS, Tax Software, User Interface (UI), User Experience (UX), Full-stack Development, Data Visualization, Charts, Tables, Software Architecture, Architecture, SQL, Ruby on Rails (RoR), Estimations, Sass, Full-stack, Tailwind CSS, Front-end, Migration, PHP, MySQL, Amazon Web Services (AWS), JavaScript Libraries, TypeScript 3, Windows, XML, MariaDB, CRM APIs, Zapier, Dashboards, Visualization, Third-party APIs, Leadership, Technical Leadership, GitHub, eCommerce, Document Processing, Documentation, Payment APIs, Payment Gateways, Payment Processing, Integration, HIPAA Compliance, HIPAA Electronic Data Interchange (EDI), Amazon API, CI/CD Pipelines, Debugging, Back-end Development, API Testing, API Design, CSS, Front-end Development, Vibe Coding, AI Integration, Fractional CTO, Search Engine Optimization (SEO), QR Codes, Apple Pay, Best Practices, Problem Solving, Test-driven Deployment, AI Programming, AI Design, AI-generated Code, Automation, Web App Development, Mobile First, Vercel, Three.js, Figma to React, Security, Reliability, Twilio, SMS, Scheduling, Real-time Systems, Large Language Models (LLMs)

Web Team Lead

2019 - 2022

Flutter Entertainment

Led a cross-functional engineering team delivering a React/Java-based casino web interface used by PokerStars Casino customers at scale.
Drove improvements in architecture, automation, and testing practices, shaping the overall quality strategy for the web platform.
Ensured adherence to security and compliance requirements across regulated casino products serving a large, global user base.
Coordinated with multiple internal teams to plan and deliver a public API rollout, enabling reliable integration across the organization.

Technologies: Amazon Web Services (AWS), Cucumber, Vue SSR, Mocha, Cypress, PHP, React, JavaScript, APIs, jQuery, HTML5, Agile Software Development, CSS3, Node.js, MongoDB, Functional Programming, Class-based OOP, Adobe Photoshop, Prototyping, Material UI, React Redux, Storybook, Apache, Unit Testing, Jest, Google Analytics, Web Development, WebSockets, REST, SCSS, Back-end, Web Applications, TypeScript, API Integration, Code Review, JSON, SaaS, User Interface (UI), User Experience (UX), Bootstrap, Full-stack Development, Data Visualization, Charts, Tables, Software Architecture, Architecture, SQL, Estimations, Next.js, Full-stack, Front-end, Migration, MySQL, Laravel, JavaScript Libraries, TypeScript 3, Windows, Google Maps, XML, MariaDB, Monday.com, CRM APIs, Animation, Gamification, Dashboards, Visualization, Third-party APIs, Leadership, Technical Leadership, GitHub, eCommerce, Documentation, Integration, HIPAA Compliance, HIPAA Electronic Data Interchange (EDI), Amazon API, CI/CD Pipelines, Debugging, Back-end Development, API Testing, API Design, CSS, Front-end Development, Search Engine Optimization (SEO), Apple Pay, Best Practices, Problem Solving, Test-driven Deployment, Automation, Web App Development, Mobile First, Vercel, WebGL, Three.js, Figma to React, Security, Reliability, Twilio, SMS, Scheduling, Message Queues, Queuing Systems, Task Scheduling, Real-time Systems, Real-time Data

Platform Team Lead

2018 - 2019

The Stars Group

Architected and developed a full game development kit (GDK) and supporting environment used to integrate and operate multiple third-party games.
Enabled integration of multiple third-party game studios through a standardized GDK pipeline, supporting global vendor onboarding.
Contributed core components to in-house slot games, ensuring engine stability and performance in production environments.
Collaborated closely with QA, DevOps, delivery, and external vendor teams to coordinate releases and resolve integration issues.
Improved the game integration process through automation, tooling, and workflow optimizations, reducing manual effort and errors.
Ensured security and compliance best practices across casino products operating in regulated, high-traffic environments.

Technologies: Jenkins, Apache Maven, Gulp, Python, Java, JavaScript, APIs, jQuery, HTML5, React, Cross-platform, Agile Software Development, CSS3, Node.js, MongoDB, Functional Programming, Class-based OOP, Charles, Concurrent Programming, Cocos2d, Adobe Photoshop, Prototyping, React Redux, Storybook, Apache, Unit Testing, Google Analytics, Web Development, WebSockets, REST, SCSS, Back-end, Web Applications, TypeScript, API Integration, Code Review, JSON, SaaS, Google Cloud Platform (GCP), User Interface (UI), User Experience (UX), Full-stack Development, Data Visualization, Charts, Tables, Software Architecture, Architecture, SQL, Estimations, Full-stack, Front-end, Migration, PHP, MySQL, Amazon Web Services (AWS), JavaScript Libraries, Windows, XML, Animation, Gamification, Dashboards, Visualization, Third-party APIs, Technical Leadership, GitHub, eCommerce, Documentation, Integration, CI/CD Pipelines, Debugging, Back-end Development, API Testing, API Design, CSS, Front-end Development, Search Engine Optimization (SEO), Best Practices, Problem Solving, Reliability, SMS, Message Queues, Real-time Data

HTML5 Game Developer

2015 - 2018

The Stars Group

Developed cross-platform HTML5 casino games using Cocos2d/JavaScript, contributing to the early game portfolio of PokerStars Casino.
Delivered table and slot games for PokerStars Casino, including award-winning titles recognized by industry publications.
Improved game engine performance and stability, with a focus on low-end mobile devices and cross-platform consistency.
Researched emerging technologies and built multiple VR/AR game prototypes to assess future product opportunities.

Technologies: Cocos2d-JS, JavaScript, jQuery, HTML5, Cross-platform, Node.js, Functional Programming, Class-based OOP, Charles, Concurrent Programming, Cocos2d, Adobe Photoshop, Prototyping, React Redux, Apache, Unit Testing, WebSockets, REST, Back-end, Web Applications, API Integration, JSON, SaaS, User Interface (UI), User Experience (UX), Data Visualization, Charts, Tables, Estimations, Full-stack, NW.js, Front-end, Migration, MySQL, React, APIs, JavaScript Libraries, Software Architecture, Windows, XML, Animation, Gamification, Dashboards, Visualization, Third-party APIs, Technical Leadership, GitHub, eCommerce, Documentation, Integration, Debugging, Back-end Development, API Testing, API Design, CSS, Front-end Development, Best Practices, Problem Solving

Co-founder | Developer | Project Manager

2002 - 2015

Brilliant Group

Co-founded and delivered over 100 client projects across web, eCommerce, and custom software, acting as lead engineer and project owner.
Designed and implemented payment and transaction systems using providers such as PayPal, Stripe, and Authorize.net.
Built, managed, and scaled small engineering teams across multiple concurrent projects while remaining a primary contributor.
Ranked consistently among the top 1% of freelancers on a global platform with over 300,000 competing professionals.
Delivered solutions across a wide range of CMS and platforms, adapting quickly to diverse business domains and requirements.

Technologies: APIs, jQuery, HTML5, PayPal API, Google Maps, Laravel, React, Authorize.net, WebStorm, Stripe API, CSS3, Vue, Node.js, MongoDB, Express.js, Jasmine-jQuery, Freelancing, Class-based OOP, PhpStorm, Adobe Photoshop, Prototyping, Material UI, React Redux, Chakra UI, GraphQL, React Apollo, Storybook, Apache, NGINX, Unit Testing, Jest, Google Analytics, Web Development, WebSockets, REST, Stripe, SCSS, Back-end, Web Applications, TypeScript, MUI CSS, API Integration, Code Review, PostgreSQL 9, JSON, SaaS, Tax Software, Google Cloud Platform (GCP), User Interface (UI), User Experience (UX), Bootstrap, Full-stack Development, Minimum Viable Product (MVP), Data Visualization, Charts, Tables, Software Architecture, Architecture, SQL, Estimations, Sass, Next.js, Web3, Blockchain, Full-stack, Smart Contracts, Tailwind CSS, Chrome Developer Tools, NW.js, Front-end, Django, Migration, JavaScript, PHP, MySQL, JavaScript Libraries, Windows, XML, MariaDB, Monday.com, CRM APIs, Animation, Gamification, Dashboards, Visualization, Third-party APIs, Technical Leadership, GitHub, eCommerce, Document Processing, Documentation, PayPal, Payment APIs, Payment Gateways, Payment Processing, BrainTree, Integration, HIPAA Electronic Data Interchange (EDI), Amazon API, Debugging, Back-end Development, Fractional CTO, Search Engine Optimization (SEO), Best Practices, Healthcare, Scheduling, Message Queues, Queuing Systems, Task Scheduling, Real-time Systems

Experience

GeneFood

https://mygenefood.app/

GeneFood is a health and nutrition platform that processes genetic data to generate personalized insights and recommendations based on current scientific research. I built the platform from scratch, owning architecture, data pipelines, and core product decisions. The system combines complex genome analysis logic with modern web infrastructure, and more recently incorporates AI-assisted workflows to accelerate research synthesis, documentation, and insight generation while maintaining scientific rigor and data integrity.

Plan Over Mood

https://planovermood.com/

Plan Over Mood is a subscription-based fitness platform built for a Canadian fitness influencer with over 1 million YouTube subscribers. I designed and developed the platform end-to-end, including landing experience, custom Stripe subscription flows, payments, and lifecycle automation, aligning technical decisions with audience growth and monetization strategy.

Ignition

https://www.ignitionapp.com/

Ignition is a SaaS platform used by accounting firms and professional services businesses to manage proposals, billing, payments, and client engagement. I served as a team lead and senior individual contributor, leading a cross-functional engineering team while actively shaping architecture, delivery processes, and the product roadmap. I worked closely with product and business stakeholders to align technical execution with customer value, scalability, and long-term platform evolution.

PokerStars Casino

PokerStars Casino is a large-scale, regulated online gaming platform operating across multiple countries and jurisdictions. Over several years, I progressed from senior engineer to team lead, contributing to player-facing web experiences, internal frameworks, and platform integrations. I led teams delivering React-based applications and APIs, worked within strict security and compliance requirements, and helped evolve development standards, testing practices, and delivery processes for a high-traffic, mission-critical product.

Education

2025 - 2026

Master's Degree in Executive Business Administration (EMBA)

Quantic School of Business and Technology - Washington DC, USA

2012 - 2013

Master's Degree in Computer Science

Ternopil National Economic University - Ternopil, Ukraine

2008 - 2012

Bachelor's Degree in Computer Science

Ternopil National Economic University - Ternopil, Ukraine

Certifications

SEPTEMBER 2021 - PRESENT

Advanced TypeScript

UI.dev

SEPTEMBER 2021 - PRESENT

React

UI.dev

SEPTEMBER 2021 - PRESENT

Advanced JavaScript

UI.dev

AUGUST 2021 - PRESENT

Agile Fundamentals

Udemy

Skills

Libraries/APIs

React, Stripe API, Node.js, Authorize.net, jQuery, PayPal API, Google Maps, React Redux, Stripe, REST APIs, WebGL, Vue, Jasmine-jQuery, NW.js, Amazon API, Three.js, Backbone.js, Google Maps API, Shopify API

Tools

WebStorm, Charles, PhpStorm, React Apollo, GitHub, Claude, Claude Code, Adobe Photoshop, Apache, NGINX, Google Analytics, Chrome Developer Tools, Zapier, Gulp, Apache Maven, Jenkins, Mocha, Cucumber, CircleCI, Figma, Notion

Languages

HTML, HTML5, PHP, CSS3, CSS, JavaScript, TypeScript, GraphQL, XML, Sass, SCSS, SQL, Java, Python, Ruby, TypeScript 3

Frameworks

Cocos2d, Laravel, Symfony, Next.js, Tailwind CSS, Express.js, Material UI, Jest, MUI CSS, Bootstrap, Ruby on Rails (RoR), Cypress, Vue SSR, Redux, Django

Paradigms

Concurrent Programming, Functional Programming, Cross-platform, Class-based OOP, Agile Software Development, Unit Testing, REST, Agile, API Architecture, Search Engine Optimization (SEO), Best Practices, Test-driven Deployment, Automation, Real-time Systems, Gamification, HIPAA Compliance, Sanity Testing, Testing, Management

Platforms

Windows, Linux, Visual Studio Code (VS Code), Twilio, Amazon Web Services (AWS), Blockchain, Vercel, Cocos2d-JS, Docker, WordPress, Google Cloud Platform (GCP)

Storage

MySQL, PostgreSQL, JSON, MongoDB, MariaDB, Databases

Industry Expertise

Healthcare

Other

Freelancing, APIs, Chakra UI, Web Development, WebSockets, Back-end, Web Applications, API Integration, Code Review, SaaS, User Interface (UI), User Experience (UX), Full-stack Development, Minimum Viable Product (MVP), Data Visualization, Charts, Tables, JavaScript Libraries, Architecture, Estimations, Web3, Full-stack, Front-end, Migration, CRM APIs, Dashboards, Third-party APIs, Leadership, Technical Leadership, eCommerce, Documentation, PayPal, Payment APIs, Payment Gateways, Payment Processing, Integration, HIPAA Electronic Data Interchange (EDI), Debugging, AI Agents, Agentic AI, Back-end Development, API Testing, API Design, Front-end Development, Vibe Coding, Fractional CTO, QR Codes, Apple Pay, Problem Solving, AI Programming, AI-generated Code, Web App Development, Mobile First, Figma to React, Reliability, SMS, Scheduling, Message Queues, Real-time Data, Storybook, PostgreSQL 9, Tax Software, Software Architecture, Smart Contracts, Monday.com, Animation, Visualization, Document Processing, AI Tools, CI/CD Pipelines, Artificial Intelligence (AI), Cursor AI, AI Integration, AI Design, Security, HIPAA, Queuing Systems, Task Scheduling, Large Language Models (LLMs), Prototyping, JetBrains IDE, BrainTree, Business Requirements, System Requirements, Statistics, Game Development, Lovable, Supabase

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