Vitaliy

Vitaliy Kuzmich
Senior PHP Engineer | Laravel · REST APIs · Full-Stack
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1,500× faster critical path · Release cycle: 2 months → 1 day · 20+ integrations unified · 12
years of web platform work

PROFESSIONAL SUMMARY
PHP engineer with twelve years across e-commerce, ERP, fintech and SaaS. Most engagements begin the
same way: the platform is slow, deploys are risky, and the code base has become something the team works
around instead of with.
Fixes that, then builds on top of it. Laravel services and APIs, a data model that survives load, queued
background work, automated deployment, and documentation the client's own developers can follow after
handover.

SELECTED ACHIEVEMENTS & IMPACT
 Made a critical processing path roughly 1,500× faster with caching, a denormalised schema and queued
background jobs, which made a planned server upgrade unnecessary.
 Brought checkout and page response times down from seconds to milliseconds. N+1 queries went, indexes
arrived, heavy work moved off the request cycle, and abandoned sessions dropped with it.
 Cut the release cycle from two months to one day, replacing manual releases that required downtime with
containerised CI/CD.
 Delivered a greenfield product from empty repository to production in under three months, so the client
started selling a quarter earlier than planned.
 Reduced new payment and partner integrations from weeks to days by consolidating 20+ external
providers behind one service layer.
 Modernised a legacy application incrementally under live traffic, with zero planned downtime, while it was
still producing incidents faster than fixes.
 Removed a procurement blocker for enterprise clients by delivering federated single sign-on across
multiple identity providers.

TECHNICAL SKILLS
Languages: PHP 7.x / 8.x, SQL, TypeScript (TS), JavaScript (ECMAScript ES6+ / ES2023), HTML5, CSS3, Bash
Frameworks: Laravel 9 / 10 / 11, Eloquent ORM, Blade, Laravel Sanctum, Laravel Passport, Laravel Horizon,
Queues and Jobs, Laravel Echo, Laravel Octane, Livewire, Inertia.js, Filament, Nova, Telescope, Artisan CLI,
Symfony components, Slim, Doctrine ORM, Composer, PSR standards
API & Architecture: RESTful API design, Laravel API Resources, GraphQL, JSON:API, OpenAPI / Swagger,
microservices, service layer and repository patterns, event-driven architecture, Domain-Driven Design (DDD),
CQRS, SOLID, clean architecture, queue-based background processing, WebSockets, legacy refactoring
Databases & Caching: MySQL, MariaDB, PostgreSQL, MongoDB, Redis, Elasticsearch, schema design,
migrations and seeders, indexing, query optimisation, N+1 elimination, caching strategies
Messaging & Integration: Redis queues, RabbitMQ, Apache Kafka, third-party API integration, payment
gateway integration, webhooks, transactional mail, scheduled tasks
Front-End: JavaScript (ECMAScript ES6+), TypeScript, React.js (Hooks, Redux Toolkit), Angular (Angular 2+,
RxJS) and AngularJS, Vue.js, Alpine.js, jQuery, Blade components, Tailwind CSS, Bootstrap, SASS, Vite,
Webpack, responsive and mobile-first design, single-page applications (SPA)
Testing & Quality: PHPUnit, Pest, Laravel feature and unit tests, Mockery, PHPStan / Larastan, PHP CS Fixer,
Xdebug, Jest, Selenium WebDriver, TDD, SonarQube, code review
DevOps & Cloud: Docker, Docker Compose, Laravel Sail, Kubernetes (K8s), Jenkins, GitHub Actions, GitLab
CI/CD, AWS (EC2, S3, RDS), Nginx, Apache, PHP-FPM, Supervisor, GNU/Linux administration, Git, Sentry
Security: OAuth 2.0, JWT, SAML 2.0 single sign-on, RBAC and policy-based authorisation, CSRF / XSS / SQL-
injection prevention, OWASP-aware secure coding, GDPR-aware data handling
Also works with: Java and Spring, Go, Python, Node.js on adjacent services
PROFESSIONAL EXPERIENCE

Senior Full-Stack Engineer — Purchase Order Management Platform
Confidential Client (NDA) · Enterprise Procurement | 10.2023 – 12.2024
 Delivered new business functionality across a procurement platform: API endpoints, service-layer rules,
relational schema changes and the JavaScript/TypeScript interface consuming them.
 Refactored tightly coupled legacy modules into testable services with explicit contracts, cutting regression
defects.
 Translated stakeholder requirements into technical specifications and shipped small, reviewable releases
on a predictable cadence.

Senior Backend Engineer — Checkout & Identity Verification System
Confidential Client (NDA) · Retail / E-Commerce Technology | 01.2022 – 08.2022
 Implemented a biometric fingerprint-authentication module for a retail checkout product: hardware
integration layer, verification service and operator interface.
 Built token-based authentication and granular authorisation policies protecting sensitive point-of-sale
operations.
 Owned packaging, deployment, on-site troubleshooting and knowledge transfer to the client's in-house
team.

Senior Backend Engineer — Customer Feedback SaaS (Greenfield)
Confidential Client (NDA) · SaaS Product | 09.2021 – 11.2021
 Built a customer-feedback platform from an empty repository: domain model, REST API, database schema,
queued background processing and deployment pipeline.
 Owned architecture and technology selection, delivering a production-ready MVP within a fixed deadline.

Senior Full-Stack Engineer — Fleet Management Platform
Confidential Client (NDA) · Logistics & Transportation | 07.2021 – 01.2022
 Maintained and progressively modernised a large legacy fleet-management application while keeping the
live service fully available.
 Investigated and fixed production issues involving data consistency, concurrent updates and third-party
telematics APIs.
 Delivered both server-side fixes and front-end improvements as the sole full-stack owner of the module.

Senior Engineer — Healthcare ERP & Analytics Service
Confidential Client (NDA) · Healthcare | 09.2020 – 04.2021
 Developed new modules and resolved defects in a production ERP processing sensitive patient and billing
records under compliance constraints.
 Delivered a high-volume analytics/reporting service on a columnar database (ClickHouse).
 Rewrote slow queries and data-access patterns, materially improving load times on the heaviest reporting
screens.

Senior Full-Stack Engineer / DevOps — Developer Tooling Platform
Confidential Client (NDA) · Atlassian Ecosystem | 12.2019 – 06.2021
 Built core extension components from scratch against a third-party platform API, integrating them with
internal enterprise services.
 Owned the DevOps chain: Docker images, Jenkins CI/CD pipelines, environment provisioning and
automated releases.
 Acted as the messaging/queueing subject-matter expert on a parallel engagement, tuning broker
integration flows for reliability.

Backend Engineer — E-Commerce Platform & SSO Integration
Confidential Clients (NDA) · Retail & Enterprise Security | 12.2017 – 03.2019
 Delivered backend features, catalogue/order logic and complex analytical SQL reporting for an online shop.
 Implemented federated single sign-on with support for multiple SAML 2.0 identity providers.
 Integrated third-party services and payment-related workflows into existing commerce systems.

Software Architect & Lead Developer — High-Load Exchange Platform
Confidential Client (NDA) · FinTech | 03.2018 – 06.2018
 Designed a microservice architecture for a high-load trading platform: service decomposition,
denormalised data model, Redis caching layer and asynchronous message bus.
  Set scalability, fault-isolation and consistency strategies for heavy concurrent workloads.
 Led technical direction for the team and reviewed performance-critical code.

Full-Stack Engineer & Linux Administrator — Integration Library, Risk Platform, ERP
Confidential Clients (NDA) · Enterprise & FinTech | 01.2015 – 05.2017
 Architected an integration library connecting a large enterprise platform with 20+ external services and
protocols.
 Built a clustered financial risk-calculation web application, owning both the computation backend and the
browser UI.
 Delivered an ERP platform from scratch and administered its production Linux stack (Nginx, application
servers, mail, DNS, FTP).

Software Engineer — Trading Platform, Real-Time Clients and Telematics
Confidential Clients (NDA) · Trading & IoT | 04.2013 – 09.2015
 Developed back-office modules, order processing, reporting and data-access layers for a clustered broker
platform.
 Built real-time clients streaming live market and GPS data over WebSocket and custom binary protocols.
 Integrated IoT hardware with backend tracking services and REST APIs.

OPEN-SOURCE & PERSONAL ENGINEERING PROJECTS
Self-hosted cloud storage server — Author of an open-source Nextcloud alternative built for low-resource
hardware: storage, sharing, authentication and HTTP API, with a JavaScript SPA front-end.
Open-source trading platform — Microservice architecture with Redis caching and a denormalised data
model, published on GitHub.
Upstream contribution — Reported and fixed a defect in a widely used open-source security framework,
found during a ProFTPD and SQL integration.

EDUCATION & PROFESSIONAL DEVELOPMENT
Master of Science, Information Security Engineering — University of Technology, Dnipro, 2007 – 2012
Professional Software Engineering Program (certified) — SoftServe, 2012

ADDITIONAL INFORMATION
Languages: English — professional working proficiency; Ukrainian — native; Russian — native
Work Style: Remote-first, distributed and cross-functional teams, Agile / Scrum / Kanban, code review
culture, mentoring of mid-level and junior engineers
Interests: Cycling, hiking, strength and endurance training, embedded electronics, open-source contribution