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Hire AndriiAndrii Naidenko
Verified Expert in Engineering
Full-stack and Mobile Developer
Athens, Central Athens, Greece
Toptal member since August 26, 2019
Bio
Andrii is a full-stack engineer with 19 years of experience and a master's degree in computer science. He specializes in Node.js back ends and Angular and React front ends. Since 2019, he's developed a 100,000-install mobile app solo. Six of his nine Toptal engagements came from repeat clients. Andrii designs AI-native delivery systems that oversee products from design to post-release crash triage, with agents managing planning, building, and verifying, involving humans only at decision points.
Portfolio
Buddy Punch
Ionic, Capacitor, Angular, TypeScript, iOS, Android, Xcode, Android Studio...
Brokerloop
JavaScript, TypeScript, Angular, Node.js, Amazon, React, Stripe...
RentWise
Node.js, Angular, MongoDB, JavaScript, Express.js, MEAN Stack...
Experience
- Full-stack - 19 years
- Node.js - 12 years
- Amazon Web Services (AWS) - 12 years
- Mobile App Development - 10 years
- Ionic - 10 years
- TypeScript - 9 years
- Angular - 9 years
- Capacitor - 7 years
Work Experience
Senior Mobile Developer
2019 - PRESENT
Buddy Punch
- Owned the iOS and Android app end-to-end as its sole developer for seven years—architecture, features, native integrations, and every store release—3,200+ commits behind a product with 100,000+ installs and a 4.9-star App Store rating.
- Carried the app through three platform generations to Angular 21, Ionic 8, and Capacitor 8, and moved iOS from CocoaPods to Swift Package Manager—so a 7-year-old codebase still ships on current tooling.
- Built Offline Mode, the product's most requested feature of 2025: employees punch in and out and take breaks with no connection, and everything reconciles with the server the moment the network returns.
- Developed the GPS layer the product sells on: background tracking during shifts, geofence enter and exit alerts, route maps, precise-location enforcement, and anti-spoofing safeguards — on phones and tablets alike.
- Replaced Ionic Appflow, which Ionic is shutting down, with fastlane on GitHub Actions: one command now builds, checks, and ships both apps to Firebase, TestFlight, or Google Play, and QA builds take 6 minutes instead of 12.
- Created the security layer end-to-end: multi-factor sign-in with passkeys, recovery codes, and trusted devices, plus native credential autofill through iOS Password AutoFill and Android Credential Manager on platform secure storage.
- Built the workflow features managers run their teams on: shift trade and cover requests with approvals, availability, time-card acknowledgment, group punch for whole crews, and manual-punch notes for kiosk mode.
- Wrote the native code where plugins fell short: a custom Capacitor plugin in Swift and Java for kiosk and guided-access mode, an in-house fork of the barcode scanner when its vendor dropped SPM, and iPad resizable-window support ahead of iPadOS 27.
- Built the release flow from branch to store: GitLab Flow branches, two release gates so the stores ship exactly the build QA verified, release waves that cap work in testing at 10 items, and Raygun and Crashlytics triage after each release.
- Client Testimonial: "When something is unclear, his question comes with a proposed answer, which makes every decision faster. I never have to chase him for status or wonder where things stand." – Nick Murphy, co-founder, Buddy Punch.
Technologies: Ionic, Capacitor, Angular, TypeScript, iOS, Android, Xcode, Android Studio, Swift, Java, CocoaPods, Ionic Appflow, Firebase, Push Notifications, Geolocation, Offline-first Development, PrimeNG, SCSS, Raygun, Google Analytics, Azure DevOps, GitHub Actions, Playwright, Bash, Mobile App Development, Capacitor Plugin Development, Tailwind CSS, APIs, Slack App, Google Analytics API, Progressive Web Applications (PWAs), API Integration, Authentication, SaaS, Code Auditing, Application Security, CI/CD Pipelines, Fastlane, Ruby, Continuous Integration (CI), Continuous Delivery (CD), Security, Mobile Security, Testing, Responsive Layout, UI Components, Debugging, Best Practices, Figma, User Experience (UX), Software Development, Software Development Lifecycle (SDLC), Barcode Reader, RESTFul APIs
Full-stack Developer
2020 - 2026
Brokerloop
- Owned the engine room of the platform: six years and 1,800+ commits on the Node.js API behind every listing, contact, and campaign — the layer brokerages depend on to run their day.
- Built the platform's own video conferencing product — scheduled rooms, live streaming, cloud recording, and screen share, syndicated to YouTube, Facebook, and Instagram — so brokerages could host their community without ever leaving it.
- Developed the revenue engine: Stripe subscriptions with tiered plans, instant mid-cycle upgrades, and credit-based limits, so brokerages could buy, upgrade, and scale without ever talking to sales.
- Built the platform's own email infrastructure — a self-hosted SMTP proxy with rate limiting, automatic failover, and bounce intelligence — so brokerage campaigns land in inboxes instead of spam folders.
- Opened the platform to AI: documented the entire API as an OpenAPI spec, then built an MCP server so assistants like Claude can run the product through it.
- Hardened the AI listing import that lets brokers add a listing from any website, with Claude parsing the page as the last fallback: reviewed it, added SSRF checks for user-supplied URLs, and fixed its runtime failures.
- Mentored the team and set the engineering bar: code reviews, on-call DevOps in AWS, and full ownership of releases — so the platform shipped on a predictable cadence.
- Gave brokerages one-click social reach: a cross-posting engine for Facebook, Instagram, X, and LinkedIn with scheduling and per-platform formatting, so one post covers every network.
- Connected print marketing to the web: QR codes generated for every listing and bio site, with scan-to-visit conversion tracked in the dashboard — so agents could finally measure their flyers.
- Put a direct line to clients in the product: SMS and MMS campaigns on Plivo with delivery tracking, so brokerages could reach their whole contact list from the same dashboard.
Technologies: JavaScript, TypeScript, Angular, Node.js, Amazon, React, Stripe, Video Conferencing, Google APIs, OData, RETS, GitFlow, Agile, Express.js, MySQL, MongoDB, Sequelize, Mongoose, OAuth 2, Docker, Mobile Development, Stripe API, Redis, Tailwind CSS, OpenAPI, Anthropic, Model Context Protocol (MCP), Firebase, Video Conferencing Bridges, HTTP Live Streaming (HLS), WebRTC, YouTube API, APIs, Slack App, SendGrid, SMTP, Chart.js, Highcharts, Google Analytics API, YouTube, Claude, API Integration, Authentication, AI-assisted Development, Agentic Coding, WebSockets, Multi-tenant SaaS, SaaS, Claude Code, Multi-tenant Architecture, Architecture, Software Architecture, Code Review, Large Language Models (LLMs), Artificial Intelligence (AI), Application Security, Authorization, Cloud Infrastructure, AI Integration, LLM Integration, Data Modeling, Data Visualization, Dashboards, API Development, AI Tools, NGINX, Testing, Responsive Layout, UI Components, Debugging, Best Practices, User Experience (UX), Integration, Software Development, Software Development Lifecycle (SDLC), RESTFul APIs, Webhooks, Back-end APIs, Rest APi, Event-driven Programming
MEAN Full-stack Developer
2022 - 2025
RentWise
- Built the entire learning engine behind the platform: course authoring, quizzes, certificates, and pacing rules that make sure renters actually absorb their rights instead of clicking to the end.
- Turned the platform into a paid product: PayPal checkout for course purchases, plus registration and activity exports so administrators could see who was actually learning.
- Brought the video library in-house: adaptive HLS streaming with quality selection, and a pipeline that imports YouTube courses with subtitles into the platform's own storage — no more dependence on a third party.
- Replaced dead PDF worksheets with living ones: budgets that total themselves as renters fill them in, plus a Q&A flow that puts housing providers one message away.
- Ran the security audit and fixed what it found: server-side request forgery, cross-site scripting, session hijacking, and broken access control — on a platform holding renters' personal data.
- Put every property on the map: an ArcGIS geocoding layer that turns an address into its neighborhood context — the services and housing around it — in one view.
- Gave tenants a place for their paperwork: leases, property photos, and issue reports in one vault, so a renter can prove what was agreed and what went wrong months later.
- Rebuilt authentication on one path: a reworked data model and JWT flow that replaced scattered ad-hoc role checks with a single rule that the entire API obeys.
- Built and maintained the platform end-to-end across three engagements from 2022 to 2025 — an education system that teaches renters and landlords their rights.
Technologies: Node.js, Angular, MongoDB, JavaScript, Express.js, MEAN Stack, Amazon Web Services (AWS), ArcGIS, GeoJSON, Slack API, Full-stack, Angular Material, PayPal, PayPal API, Video.js, HTTP Live Streaming (HLS), TinyMCE, Passport.js, JSON Web Tokens (JWT), Heroku, Amazon S3 (AWS S3), AWS Elemental MediaConvert, Amazon CloudFront, APIs, SMTP, Chart.js, API Integration, Authentication, Code Auditing, Application Security, Authorization, Security, Auditing, Data Visualization, API Development, OWASP, Testing, Responsive Layout, UI Components, Debugging, Best Practices, User Experience (UX), Integration, Software Development, RESTFul APIs, Back-end APIs, Rest APi
Senior Cross-platform Developer
2019 - 2020
USC ICT (Institute for Creative Technologies)
- Took a desktop-only mental-health support app to the phone: responsive layouts, modal scrolling, and phone-sized forms, quizzes, and assessments — so people could reach help from the device they actually carry.
- Turned a web app into a shippable product: packaged it with Ionic and Capacitor for the App Store and Google Play, so research work could reach users as a real mobile app.
- Redesigned a dozen self-help forms — journals, planners, worksheets — to work on a phone and on paper alike, so people could fill them in wherever they were, then print a clean copy.
- Fixed scoring and flow defects the research team reported across the assessments and the new-user tutorial, including a halt that trapped users mid-conversation.
Technologies: PhoneGap, Ionic, Cross-platform, Angular, Mobile App Development, NgRx, Capacitor, Cordova, Cross-platform App Development, TypeScript, SCSS, Bootstrap, Responsive Design, iOS, Android, APIs, API Integration, Authentication, Responsive Layout, Debugging, Best Practices, User Experience (UX), Software Development, Health
Senior Full-stack Developer
2014 - 2019
Freelance Clients
- Delivered a content licensing system based on blockchain technologies with a marketplace feature that makes licensing, validating, and monetizing digital content as easy as sending a Venmo payment.
- Implemented a social media marketing platform for franchise organizations and distributed teams to empower central marketing departments with a system to simultaneously distribute consistent hyper-local content for all their independent sales reps.
- Implemented a cloud-based task tracker for project coordination and sprint planning for Inovo Studios and OnCue Technology, which the client called one of the year's highlights.
- Implemented a Gitflow development process with continuous integration and delivery pipelines for microservices hosted on AWS cloud.
- Recognized as a top-rated developer with a 100% job-success score. Clients were highly satisfied with the delivered services and left positive references on the platform.
- Provided regular expert consultation and technical guidance on software development and design projects for many clients.
- Performed code reviews and optimized the software architecture and security concerns of clients' products.
- Built the web and mobile experience for Sellr, a retail platform that engages shoppers online and in the aisle to drive traffic and sales—AngularJS on the web, Ionic on mobile, with a reworked async model on the back end.
- Client Testimonial: "Andrii has been one of our best, most reliable developers on many projects. He works efficiently, communicates effectively, and cares about his quality of work." – Bruce van Zyl, OnCue Technology.
Technologies: Slack, MacOS, Webpack, Pivotal Tracker, Trello, Mocha, RabbitMQ, Chai, Sinon.JS, Koa, Algolia, Beanstalk, Bower, Domain-driven Design (DDD), Angular Universal, Toggl, Asana, Docker Hub, Gulp, Slack API, CircleCI, X (formerly Twitter) API, Kanban, GRASP, Functional Testing, Object-oriented Design (OOD), Amazon, Design Patterns, Clean Code, SOLID Principles, Continuous Integration (CI), Asynchronous Programming, Unit Testing, Architecture, Front-end Development, HTML, Next.js, Android, Redis, PostgreSQL, Mailchimp API, Redux, iOS, UML, Stripe API, Sass, Continuous Delivery (CD), PM2, Karma, Jira, RxJS, Protractor, Cordova, Visual Studio Code (VS Code), Grunt, Google API, Facebook API, OAuth 2, Less, Heroku, HTML5, jQuery UI, NoSQL, Git, jQuery, Scrum, Agile Software Development, SQL, CSS, GitFlow, Bootstrap 3+, Back-end Development, Angular Material, Test-driven Development (TDD), React, MEAN Stack, Bootstrap, Jasmine, Amazon Web Services (AWS), MySQL, Web Development, JavaScript, Mobile App Development, Full-stack, Elasticsearch, PhoneGap, Docker, Socket.IO, MongoDB, Express.js, Ionic, TypeScript, AngularJS, Angular, Node.js, NgRx, Stripe, Google Maps API, Firebase, REST APIs, Amazon S3 (AWS S3), Full-stack Development, Software as a Service (SaaS), Front-end, Back-end, Mobile Development, APIs, Slack App, SendGrid, SMTP, Chart.js, Server-side Rendering (SSR), API Integration, Authentication, WebSockets, SaaS, Software Architecture, Code Review, Code Auditing, Application Security, Authorization, Cloud Infrastructure, CI/CD Pipelines, Security, Auditing, Data Visualization, API Development, Responsive Layout, Debugging, Best Practices, User Experience (UX), Integration, Software Development, eCommerce, RESTFul APIs, Webhooks, Back-end APIs, Rest APi
Lead .NET Software Engineer
2011 - 2014
EPAM Systems
- Ran the project as scrum master for a team of 6–10: took requirements straight from the customer, ran the reviews and retrospectives, and brought every newcomer up to speed.
- Built the financial portlets that traders watch the markets through: stock exchange monitoring on the Thomson Reuters platform, running live on the client's terminals.
- Designed the MVVM-C JavaScript framework that the whole portlet suite was rebuilt on, and shipped WPF desktop apps to the Bloomberg App Portal — setting the front-end pattern the team followed.
- Brought the team its first JavaScript unit tests and a continuous integration pipeline, and made the trading apps usable on touch screens — in 2012, before either was standard.
- Trusted to hire: interviewed senior .NET and JavaScript candidates on the company's behalf, and onboarded the ones who made it in.
- Spoke to rooms of up to 100 engineers at public IT conferences on Knockout.js, TDD, JavaScript, Entity Framework, Brightcove, and the Bloomberg App Portal — the company's voice on front-end practice.
- Twice promoted in three years, from engineer to lead, on the company's own recognition of technical growth.
Technologies: MacOS, Beanstalk, Domain-driven Design (DDD), Kanban, GRASP, Functional Testing, Object-oriented Design (OOD), Amazon, Design Patterns, Clean Code, SOLID Principles, Continuous Integration (CI), Asynchronous Programming, Unit Testing, Architecture, Front-end Development, HTML, SQLite, UML, Continuous Delivery (CD), Jira, RxJS, Less, HTML5, jQuery UI, NoSQL, Git, jQuery, Scrum, Agile Software Development, SQL, CSS, Back-end Development, Angular Material, AngularJS, Jasmine, Amazon Web Services (AWS), Web Development, Full-stack, LINQ, Microsoft SQL Server, NHibernate, Entity Framework, Behavior-driven Development (BDD), Test-driven Development (TDD), MongoDB, ServiceStack, Windows Communication Foundation (WCF), Windows Presentation Foundation (WPF), C#, Knockout (Knockout.js), JavaScript, Web API, ASP.NET MVC, .NET, REST APIs, Amazon S3 (AWS S3), Full-stack Development, Software as a Service (SaaS), Front-end, Back-end, APIs, API Integration, Software Architecture, Code Review, API Development, Responsive Layout, Debugging, Best Practices, User Experience (UX), Integration, Software Development, Software Development Lifecycle (SDLC), RESTFul APIs, Back-end APIs, Rest APi
.NET Software Engineer
2007 - 2011
GlobalLogic
- Worked on CustomCD, DigitalRiver's burn-on-demand eCommerce service: the admin and partner-support web applications behind orders fulfilled across the US and Germany.
- Built the back-end services that moved orders out the door: packaging, shipment and reporting, plus the notification system telling customers where their order was.
- Integrated the PlanetPress publishing engine so every invoice and business document reached its recipient in the format they actually wanted — print, email or file.
- Built the reporting layer on Microsoft Reporting Services, so the business could finally see its order and fulfilment numbers without asking engineering.
- Integrated and maintained the enterprise resource planning system that unified planning, accounting and analysis across the company's operations.
Technologies: Subversion (SVN), Object-oriented Design (OOD), Design Patterns, SOLID Principles, Asynchronous Programming, Unit Testing, Front-end Development, HTML, Microsoft SQL Server, UML, jQuery, Scrum, Agile Software Development, SQL, CSS, Back-end Development, Web Development, Windows Forms (WinForms), Windows Communication Foundation (WCF), C#, JavaScript, ASP.NET, .NET, Full-stack Development, Software as a Service (SaaS), Front-end, Back-end, APIs, API Integration, API Development, Debugging, Best Practices, Software Development, eCommerce
Project History
Buddy Punch — Time Tracking and Scheduling for Shift Teams
https://buddypunch.com/The time-tracking and scheduling app from Buddy Punch, a US workforce-management SaaS, allows employees to clock in and out, take breaks, view schedules, and request shift changes; managers can approve, edit, and run entire crews from their phones. iOS and Android from one Ionic/Capacitor codebase, 100,000+ installs, 4.9 stars on the App Store.
I have been its sole developer since 2019. In that time the app went through three platform generations to Angular 21, Ionic 8 and Capacitor 8, gained an offline mode that reconciles punches when the network returns, a GPS layer with background tracking, geofence alerts and anti-spoofing safeguards, multi-factor sign-in with passkeys, native credential autofill, a full dark-mode restyle, Spanish localisation and a push-notification migration to Firebase — plus a custom Capacitor plugin in Swift and Java where no plugin existed. I also replaced Ionic Appflow with Fastlane in GitHub Actions, and QA builds now take half as long.
Technologies: Ionic, Capacitor, Angular, TypeScript, Swift, Java, iOS, Android, Firebase Cloud Messaging, Geolocation, Offline-first, Capacitor Plugin Development, Swift Package Manager, CocoaPods, Ionic Appflow, Fastlane, PrimeNG, SCSS, Raygun, Google Analytics.
I have been its sole developer since 2019. In that time the app went through three platform generations to Angular 21, Ionic 8 and Capacitor 8, gained an offline mode that reconciles punches when the network returns, a GPS layer with background tracking, geofence alerts and anti-spoofing safeguards, multi-factor sign-in with passkeys, native credential autofill, a full dark-mode restyle, Spanish localisation and a push-notification migration to Firebase — plus a custom Capacitor plugin in Swift and Java where no plugin existed. I also replaced Ionic Appflow with Fastlane in GitHub Actions, and QA builds now take half as long.
Technologies: Ionic, Capacitor, Angular, TypeScript, Swift, Java, iOS, Android, Firebase Cloud Messaging, Geolocation, Offline-first, Capacitor Plugin Development, Swift Package Manager, CocoaPods, Ionic Appflow, Fastlane, PrimeNG, SCSS, Raygun, Google Analytics.
Brokerloop | Professional Network and Marketing Platform for the Real Estate Community
https://www.brokerloop.com/Brokerloop exists to empower real estate brokerages and agents everywhere with better networking and marketing tools. It provides a suite of collaboration tools built on top of the social layer. It allows using community features, creating groups, hosting and joining live rooms, leveraging lead capture tools, and more to grow a professional network.
I owned the Node.js platform API end to end for six years: MLS listing ingestion, CRM and contacts, subscription billing on Stripe, a self-hosted email infrastructure, and the live-streaming events platform brokerages host their community on.
Technologies:
Node.js, Express.js, TypeScript, AngularJS, React, MongoDB, MySQL, Mongoose, Sequelize, Stripe, Redis, Haraka, SendGrid, AWS, Docker, OpenAPI, RETS, OData, Socket.IO, WebRTC, HLS, YouTube API, Google APIs, GitFlow, and MCP.
I owned the Node.js platform API end to end for six years: MLS listing ingestion, CRM and contacts, subscription billing on Stripe, a self-hosted email infrastructure, and the live-streaming events platform brokerages host their community on.
Technologies:
Node.js, Express.js, TypeScript, AngularJS, React, MongoDB, MySQL, Mongoose, Sequelize, Stripe, Redis, Haraka, SendGrid, AWS, Docker, OpenAPI, RETS, OData, Socket.IO, WebRTC, HLS, YouTube API, Google APIs, GitFlow, and MCP.
Auditdesk — Code Audit Workbench with Claude Agents and Human Review
https://toptal.naidenko.dev/auditA code-audit workbench I built to tell a client what to fix first in their codebase and what can wait, before a launch, a fundraise, or a handover. Scanners go first: gitleaks over every branch's history, osv-scanner over the dependencies, and Semgrep. Then a Claude agent reads the code for each chosen aspect, from security and the data model to mobile apps, LLM integrations, and multi-tenancy, through read-only tools and a checklist.
I review every finding before the client sees it. The HTML and PDF report opens with what to fix before sign-off, and gives each finding its evidence by file and line, the fix, and links to the OWASP Top 10, ASVS, MASVS, and CWE. Findings export as SARIF and issue drafts; a re-audit re-checks each one.
The client's code is never run, every secret gitleaks finds is masked before the model sees it, and files the client keeps from AI tools stay out of the agents' reach. A sample report is on the project's page; the source is public at github.com/anaidenko/auditdesk. An eval scores it against the answer keys of known defects. I built it AI-first with Claude Code.
Technologies: Next.js, React, TypeScript, PostgreSQL, Prisma, Claude Agent SDK, Anthropic API, Docker, Playwright, GitHub Actions
I review every finding before the client sees it. The HTML and PDF report opens with what to fix before sign-off, and gives each finding its evidence by file and line, the fix, and links to the OWASP Top 10, ASVS, MASVS, and CWE. Findings export as SARIF and issue drafts; a re-audit re-checks each one.
The client's code is never run, every secret gitleaks finds is masked before the model sees it, and files the client keeps from AI tools stay out of the agents' reach. A sample report is on the project's page; the source is public at github.com/anaidenko/auditdesk. An eval scores it against the answer keys of known defects. I built it AI-first with Claude Code.
Technologies: Next.js, React, TypeScript, PostgreSQL, Prisma, Claude Agent SDK, Anthropic API, Docker, Playwright, GitHub Actions
Claude Code Plugin Marketplace — Open-source Developer Tooling
https://github.com/anaidenko/claude-pluginsA public marketplace that distributes my open-source plugins for Claude Code, Anthropic's agentic coding tool. The marketplace hosts a validated manifest, checked automatically in CI, so a broken plugin definition can never be published, and lets any developer install the plugins with a single command.
Two plugins ship through it. claude-notify-resume delivers desktop notifications that carry the name of the conversation that produced them and reopen that exact session when clicked — built for a workflow running many parallel agent sessions at once. Claude-video-digest turns any video into a readable digest: a timestamped contact sheet, extracted frames, and a transcript, with a loudness probe that detects silent audio tracks so the tool never invents captions for a video that has no speech.
Both plugins ship with zero runtime dependencies, their own test suites running on macOS and Linux, and full documentation. I designed, built, released, and maintained all three repositories, including semantic versioning and changelogs.
Technologies:
Node.js, Bash, TypeScript, Git, GitHub Actions, CI/CD Pipelines, Docker, FFmpeg, macOS, and Linux.
Two plugins ship through it. claude-notify-resume delivers desktop notifications that carry the name of the conversation that produced them and reopen that exact session when clicked — built for a workflow running many parallel agent sessions at once. Claude-video-digest turns any video into a readable digest: a timestamped contact sheet, extracted frames, and a transcript, with a loudness probe that detects silent audio tracks so the tool never invents captions for a video that has no speech.
Both plugins ship with zero runtime dependencies, their own test suites running on macOS and Linux, and full documentation. I designed, built, released, and maintained all three repositories, including semantic versioning and changelogs.
Technologies:
Node.js, Bash, TypeScript, Git, GitHub Actions, CI/CD Pipelines, Docker, FFmpeg, macOS, and Linux.
naidenko.dev — Personal Site on Next.js, React, and Cloudflare Workers
https://toptal.naidenko.dev/My personal site, built as a small production system rather than from a template: one page with my work and my open-source Claude Code plugins. The code is public at github.com/anaidenko/naidenko.dev.
Next.js exports the pages as static HTML, and a Cloudflare Worker runs the parts that need a server. Two cookieless counters, GoatCounter and one of my own, mean the site needs no consent banner. Mine stores each visit, its clicks, and its visible time in Cloudflare D1, tells a returning visitor from a new one via a keyed hash, and a daily job drops after 13 months, and charts it all by day and by source on a password-protected page.
Vitest covers the Worker and the helpers; Playwright with Axe runs end-to-end and accessibility tests; and GitHub Actions runs every check in CI. The pages also serve Markdown and llms.txt for AI agents. I built it AI-first with Claude Code.
Technologies: Next.js, React, TypeScript, Tailwind CSS, Cloudflare Workers, Cloudflare D1, SQL, Vitest, Playwright, and GitHub Actions
Next.js exports the pages as static HTML, and a Cloudflare Worker runs the parts that need a server. Two cookieless counters, GoatCounter and one of my own, mean the site needs no consent banner. Mine stores each visit, its clicks, and its visible time in Cloudflare D1, tells a returning visitor from a new one via a keyed hash, and a daily job drops after 13 months, and charts it all by day and by source on a password-protected page.
Vitest covers the Worker and the helpers; Playwright with Axe runs end-to-end and accessibility tests; and GitHub Actions runs every check in CI. The pages also serve Markdown and llms.txt for AI agents. I built it AI-first with Claude Code.
Technologies: Next.js, React, TypeScript, Tailwind CSS, Cloudflare Workers, Cloudflare D1, SQL, Vitest, Playwright, and GitHub Actions
RentWise | Rental Education Platform
https://www.rentwise.org/This rental education platform focuses on the housing rental market that increases community awareness and support for quality, affordable rental housing.
I built the learning engine the platform runs on — course authoring, quizzes, certificates and pacing rules — plus PayPal checkout, adaptive video streaming, an ArcGIS mapping layer and the security hardening that followed the audit.
Technologies:
MEAN, Angular, Angular Material, Node.js, Express.js, MongoDB, AWS, Amazon S3, CloudFront, AWS Elemental MediaConvert, Heroku, PayPal API, JWT, Passport.js, ArcGIS, GeoJSON, video.js, HLS, and TinyMCE.
I built the learning engine the platform runs on — course authoring, quizzes, certificates and pacing rules — plus PayPal checkout, adaptive video streaming, an ArcGIS mapping layer and the security hardening that followed the audit.
Technologies:
MEAN, Angular, Angular Material, Node.js, Express.js, MongoDB, AWS, Amazon S3, CloudFront, AWS Elemental MediaConvert, Heroku, PayPal API, JWT, Passport.js, ArcGIS, GeoJSON, video.js, HLS, and TinyMCE.
AI-native Engineering System for a Mobile Product Team
An engineering system I designed and built so that AI coding agents can carry a production mobile product safely, rather than just autocompleting code. It covers the full delivery cycle: planning, an independent AI plan review, implementation inside isolated Git worktrees, AI code review, verification, QA distribution, and release.
Its distinguishing feature is that the guardrails are deterministic rather than advisory: eleven hooks enforce mechanically what documentation alone cannot — blocking credentials from ever reaching a session, refusing a client-facing message missing its recipients, catching edits that silently land in the wrong place. Each exists because a specific failure happened once and was made impossible afterward.
Around it sits a self-improving knowledge base of 131 codified lessons, kept in sync by an automated check. Verification is multi-modal: agents drive real iOS and Android devices, read QA screen recordings, and capture on-screen motion as video, instead of trusting a green build. I also designed the release process that the team now runs.
Technologies:
AI Agents, Prompt Engineering, Model Context Protocol (MCP), Claude Code, Playwright, Node.js, Bash, Python, Git, CI/CD Pipelines, and Azure DevOps.
Its distinguishing feature is that the guardrails are deterministic rather than advisory: eleven hooks enforce mechanically what documentation alone cannot — blocking credentials from ever reaching a session, refusing a client-facing message missing its recipients, catching edits that silently land in the wrong place. Each exists because a specific failure happened once and was made impossible afterward.
Around it sits a self-improving knowledge base of 131 codified lessons, kept in sync by an automated check. Verification is multi-modal: agents drive real iOS and Android devices, read QA screen recordings, and capture on-screen motion as video, instead of trusting a green build. I also designed the release process that the team now runs.
Technologies:
AI Agents, Prompt Engineering, Model Context Protocol (MCP), Claude Code, Playwright, Node.js, Bash, Python, Git, CI/CD Pipelines, and Azure DevOps.
Virtual Research Navigator — Conversational Mental-health Support on Mobile
https://ict.usc.edu/The Virtual Research Navigator of USC's Institute for Creative Technologies is a research institute known for virtual humans and conversational agents. It guides people through a mental-health support program by talking to them: a conversational agent answers in audio and video, and the surrounding app carries the self-help material — quizzes, assessments, journals, planners, and worksheets.
I joined the team to take that Angular interface off the desktop and onto the phone. I packaged it with Ionic and Capacitor for the App Store and Google Play, rebuilt the layouts, modal scrolling, and forms for a phone-sized screen, redesigned a dozen self-help forms to work on screen and on paper alike, and fixed scoring and flow defects the research team reported across the assessments and the new-user tutorial, including a halt that trapped users mid-conversation.
Technologies: Angular, NgRx, Ionic, Capacitor, Cordova, TypeScript, SCSS, Bootstrap, Responsive Design, iOS, Android.
I joined the team to take that Angular interface off the desktop and onto the phone. I packaged it with Ionic and Capacitor for the App Store and Google Play, rebuilt the layouts, modal scrolling, and forms for a phone-sized screen, redesigned a dozen self-help forms to work on screen and on paper alike, and fixed scoring and flow defects the research team reported across the assessments and the new-user tutorial, including a halt that trapped users mid-conversation.
Technologies: Angular, NgRx, Ionic, Capacitor, Cordova, TypeScript, SCSS, Bootstrap, Responsive Design, iOS, Android.
BitRights Platform for Licensing on Blockchain
A revolutionary content licensing system based on blockchain technologies which make licensing, validating, and monetizing digital content as easy as sending a Venmo payment. Built the entire front end and public-facing app from scratch and actively contributed to the back-end development.
I built the entire front end and public-facing app and contributed to the Node.js API: IPFS storage for licensed content, Merkle-tree proofs, and payments.
Technologies:
Angular, Angular Universal, Bootstrap 4, TypeScript, Chart.js, ng2-charts, Node.js, Express, Mongoose, Stripe, AWS, Docker, RabbitMQ, JWT, SendGrid, IPFS, Stellar, Merkle Tree, GitFlow, and CircleCI.
I built the entire front end and public-facing app and contributed to the Node.js API: IPFS storage for licensed content, Merkle-tree proofs, and payments.
Technologies:
Angular, Angular Universal, Bootstrap 4, TypeScript, Chart.js, ng2-charts, Node.js, Express, Mongoose, Stripe, AWS, Docker, RabbitMQ, JWT, SendGrid, IPFS, Stellar, Merkle Tree, GitFlow, and CircleCI.
Seller Platform for Retailers
An innovative technology solution that enables retailers to engage shoppers online and in the aisle - driving traffic and sales. Contributed mainly to front-end development both for web (AngularJS) and mobile (Ionic). Refined the back-end infrastructure, improved the async programming model, and implemented some business logic related to the dashboard.
Technologies:
MEAN, Ionic, AngularJS, TypeScript, MySQL, Socket.IO, Chart.js, Stripe, OAuth, Passport, Algolia Search, Segment, New Relic, Mailgun, MailChimp, Heroku, CloudFront, CircleCI, GitFlow, Git.
Technologies:
MEAN, Ionic, AngularJS, TypeScript, MySQL, Socket.IO, Chart.js, Stripe, OAuth, Passport, Algolia Search, Segment, New Relic, Mailgun, MailChimp, Heroku, CloudFront, CircleCI, GitFlow, Git.
TeamPlanner: A Modern and Smart Cloud-based Task Tracker
TeamPlanner is a cloud-based task tracker for project coordination and sprint planning. It was designed specifically for Inovo Studios and OnCue, and the client called it one of the highlights of the year. I built the solution from scratch using the MEAN stack, tightly integrating it with Slack messaging using OAuth2, and connected Socket.IO for real-time communication.
Technologies:
MEAN, Material Framework, Socket.IO, Chart.js, Heroku, Amazon S3, CloudFront, Passport, Slack, NewRelic, Mailgun, Grunt, Lodash, Less, Beanstalk, and Git.
Technologies:
MEAN, Material Framework, Socket.IO, Chart.js, Heroku, Amazon S3, CloudFront, Passport, Slack, NewRelic, Mailgun, Grunt, Lodash, Less, Beanstalk, and Git.
YipYip Platform for Enterprise Blogging and Social Media Posting
YipYip is an enterprise blogging and social media posting platform for franchise organizations and distributed teams. The solution is designed to empower central marketing departments with a system to distribute consistent, hyper-local content for all independent sales reps within the franchise simultaneously. I developed the major part of the front end from scratch, and oversaw the social network integration on the back end.
Technologies:
AngularJS, Material Framework, CoffeeScript, Jade, Express.js, Amazon S3, LABjs, Grunt, Lodash, Karma, Mocha, Jasmine, and Heroku.
Technologies:
AngularJS, Material Framework, CoffeeScript, Jade, Express.js, Amazon S3, LABjs, Grunt, Lodash, Karma, Mocha, Jasmine, and Heroku.
CardKit Website Builder
CardKit is a cloud-based web development platform that allows users to create HTML5 web and mobile sites through the use of their online drag and drop tools following material design. I improved the user experience via a responsive material design, upgraded to the latest MEAN stack, extended business logic, and integrated third-party websites built with CardKit.
Technologies:
MEAN, Material Framework, Amazon S3, CloudFront, Route 53, Stripe payments, FileStack, OAuth2, NewRelic, Passport, and Medium Editor
Technologies:
MEAN, Material Framework, Amazon S3, CloudFront, Route 53, Stripe payments, FileStack, OAuth2, NewRelic, Passport, and Medium Editor
Spotlight Casting Platform
https://spotlight.com/A revolutionary end-to-end service for the professional casting industry, which is used to find talent, manage and record auditions, share video clips, and collaborate on role decisions.
I worked on the back-end services behind auditions and video clips: ServiceStack and Web API endpoints over SQL Server, with FFmpeg handling the clip processing.
I worked on the back-end services behind auditions and video clips: ServiceStack and Web API endpoints over SQL Server, with FFmpeg handling the clip processing.
Education
2005 - 2010
Master's Degree in Computer Science
Kharkiv National University of Radio Electronics - Kharkiv, Ukraine
Certifications
NOVEMBER 2013 - PRESENT
Programming in HTML5 with JavaScript and CSS3
Microsoft
APRIL 2013 - PRESENT
Windows Communication Foundation Development with Microsoft .NET Framework
Microsoft
FEBRUARY 2012 - PRESENT
Web Apps Development with MS .NET Framework
Microsoft
Skills
Libraries/APIs
Node.js, Stripe API, Flexbox, Stripe, REST APIs, API Development, Back-end APIs, React, RxJS, Socket.IO, jQuery, jQuery UI, Facebook API, Google API, X (formerly Twitter) API, Slack API, Sockets, Google Maps API, Google APIs, Playwright, OpenAPI, YouTube API, CocoaPods, Chart.js, Highcharts, Google Analytics API, Windows Forms (WinForms), Web API, Entity Framework, LINQ, Mailchimp API, Sinon.JS, Chai, NgRx, FFmpeg, ArcGIS, WebRTC, PayPal API, Passport.js, PrimeNG
Tools
Slack, Git, PM2, Sequelize, Mongoose, Capacitor, Claude Code, Claude, Fastlane, Figma, CircleCI, Docker Hub, Jira, Karma, Asana, Toggl, Webpack, Gulp, Grunt, Angular Universal, Xcode, Android Studio, SendGrid, Google Analytics, Claude Agent SDK, NGINX, RabbitMQ, Mocha, Trello, Pivotal Tracker, Bower, Beanstalk, Subversion (SVN), Amazon CloudFront, Vitest, Prisma
Languages
HTML, TypeScript, JavaScript, HTML5, CSS, SQL, SCSS, C#, Sass, Less, Bash, UML, Python, Swift, Java, Ruby
Frameworks
Bootstrap, Angular, AngularJS, Ionic, Angular Material, Bootstrap 3+, OAuth 2, Jasmine, Express.js, Tailwind CSS, JSON Web Tokens (JWT), Knockout (Knockout.js), Redux, .NET, Protractor, Agentic Frameworks, Next.js, ASP.NET, ASP.NET MVC, Windows Presentation Foundation (WPF), ServiceStack, NHibernate, PhoneGap, Koa, Video.js
Paradigms
Test-driven Development (TDD), Agile Software Development, Kanban, Clean Code, Asynchronous Programming, Continuous Integration (CI), Continuous Delivery (CD), MEAN Stack, REST, Mobile Development, Search Engine Optimization (SEO), Testing, Responsive Layout, Best Practices, Unit Testing, Functional Testing, Scrum, GRASP, Design Patterns, Object-oriented Design (OOD), Agile, Model Context Protocol (MCP), Azure DevOps, Behavior-driven Development (BDD), Automation, Offline-first Development, Cross-platform, Event-driven Programming
Platforms
MacOS, Docker, Heroku, Amazon Web Services (AWS), iOS, Android, Visual Studio Code (VS Code), Firebase, Amazon, YouTube, Algolia
Storage
MongoDB, MySQL, Amazon S3 (AWS S3), NoSQL, Redis, Microsoft SQL Server, PostgreSQL, SQLite, Elasticsearch
Other
Cordova, SOLID Principles, GitFlow, Web Development, Mobile App Development, Front-end Development, Full-stack, Back-end Development, Slack App, Full-stack Development, Software as a Service (SaaS), Front-end, Back-end, APIs, CI/CD Pipelines, Ionic Appflow, Push Notifications, Geolocation, API Integration, Authentication, AI-assisted Development, Agentic Coding, Code Review, Code Auditing, Auditing, AI Tools, UI Components, Debugging, User Experience (UX), Integration, Software Development, Software Development Lifecycle (SDLC), RESTFul APIs, Rest APi, Architecture, Video Conferencing, OData, AI Agents, Prompt Engineering, SMTP, Server-side Rendering (SSR), GitHub Actions, Raygun, WebSockets, Multi-tenant SaaS, SaaS, Multi-tenant Architecture, Software Architecture, Large Language Models (LLMs), Artificial Intelligence (AI), Application Security, Authorization, Cloud Infrastructure, Security, Agentic AI, AI Integration, LLM Integration, Data Modeling, Data Visualization, Dashboards, Mobile Security, OWASP, Webhooks, Windows Communication Foundation (WCF), Domain-driven Design (DDD), Progressive Web Applications (PWAs), GeoJSON, RETS, Open Source, Process Design, Anthropic, Video Conferencing Bridges, HTTP Live Streaming (HLS), PayPal, TinyMCE, AWS Elemental MediaConvert, Capacitor Plugin Development, Cross-platform App Development, Responsive Design, Cloudflare, Web Accessibility, Web Scraping, Barcode Reader, eCommerce, Health
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