Denys Medvid

Full Stack Software Engineer

Denys Medvid

Software Engineer

Full stack engineer

Backend-developer

About Me

I am a full stack software engineer. I take pleasure when a raw idea from a paper becomes implemented in real life. In my job I try to implement best practices, and solutions because I believe that in long distance it is more profitable than fast and low quality solutions. Life is a movement, so I always try to follow the latest news in the software world to keep myself updated.

In my teenages i carried away by the ideas of free and open-source software (FOSS), which are deep in my mind nowadays. Ideas of collective work under common issues, and solving common problems. In my work I strongly prefer to use open-source solutions. I believe that open-source tools become better and more protected than proprietary software, and also give us better possibilities for developing end products.

In my free time I like to go outside with my wife, walk in a park, museum, or spend a couple of hours playing poker or some video game with my friends. Also, i like to fly and assemble FPV Drones, and build small DIY electronics on microcontrollers.

Name Denys Medvid
E-mail
Address Ukraine, Kyiv

What I Do

Backend

Develop applications based on Python, PHP, Symfony / Doctrine, have experience with Yii, alongside other server-side technologies.

Frontend

I work with ReactJs, Redux, and MobX. Prefer use TypeScript which gives me more type control inside an application and clearer architecture.

Administration

I can configure a gnu/linux server, with web servers, DBMS, mail services, configure CI/CD. I understand and use Docker.

Cpp

Can write programs with C or Cpp, using Qt Framework, and STL, Generic programming.

Architecture

I use principles: YAGNI, DRY, KIS, SOLID, GRASP, TDD, DDD when creating software architecture.

Databases

Create architecture of databases using normal forms, normalization etc.

Curriculum Vitae

Professional Summary

Senior Full Stack Engineer focused on backend-heavy SaaS development, system architecture, and production infrastructure. Experienced with EdTech platforms, LMS and LTI integrations, payment systems, REST APIs, dashboards, asynchronous document-processing pipelines, and legacy modernization.

Result-oriented engineer focused on solving real business needs — shipping features that drive customer value, scaling production systems, and keeping critical infrastructure reliable.

Main stack: PHP, Symfony, Doctrine ORM, MariaDB, Redis, React, TypeScript, Linux, Nginx, GitLab CI/CD, Docker.

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Experience

2018 - Present

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Senior Full Stack Engineer with Backend & Architecture Focus

Built and maintained project, a production EdTech SaaS platform for plagiarism detection and academic integrity. Worked across backend services, frontend, LMS integrations, payments, production infrastructure, and background processing.

Built and maintained backend services on a production EdTech SaaS serving 2.2M+ user accounts and processing 190K–360K plagiarism checks per month, using PHP, Symfony, Doctrine ORM, MariaDB, and Redis.
Delivered LMS integrations with Canvas, Moodle, Google Classroom, Blackboard, Schoology, and Brightspace — including LTI 1.1, 1.3 (JWT, Deep Linking, AGS), and Canvas SaaS LTI 2.0 — embedding plagiarism workflows directly inside instructor tooling.
Shipped Stripe and PayPal payment workflows: subscription billing, recurring invoices, webhook signature verification, and promo codes — directly supporting revenue and customer-facing billing.
Contributed to AI-generated text detection and authorship/fingerprint analysis: queued profile teaching, cross-text similarity checks, and auto-scaling detection nodes on AWS.
Built React + TypeScript frontends (customer profile, public report viewer, admin panel, PDF generation) and designed REST APIs as an OpenAPI 3.0 contract (~105 public endpoints) plus B2B, Chrome extension, Google Docs add-on, and webhook contracts.
Implemented TOTP two-factor authentication (backup codes and audit logging), OAuth2 social login, JWT for LTI 1.3, reCAPTCHA, and per-domain access voters — hardening account access across instructor and admin surfaces.
Built asynchronous document-processing pipelines with Symfony console workers, Google Pub/Sub, and database-backed queues; wired production observability across Sentry, Graylog, and Grafana/InfluxDB so incidents are diagnosable from dashboards.
Led two major Symfony migrations (3.4 → 4.4 → 5.4 LTS) with zero production downtime, backed by a PHPUnit suite (~629 test files) running in parallel via ParaTest plus PHPStan and php-cs-fixer enforced as GitLab CI gates.

2012 - 2018

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Software Engineer / Full Stack Developer

Worked as a software engineer on web application development, maintenance, integrations, payment workflows, APIs, dashboards, and legacy system support.

Contributed to backend and frontend functionality using PHP, Symfony, Doctrine, JavaScript, CodeIgniter, and legacy custom frameworks.
Maintained legacy PHP systems while supporting ongoing product development.

July 2010 - September 2012

Intuitec

Full Stack Software Engineer

I have created a couple of projects with Yii framework, JS, database architecture, and integrations with Google Calendar and have created a custom calendar UI based on jQuery, with drag-and-drop events, schedules, etc.

August 2009 - July 2010

Freelancer

Full Stack Software Engineer

Name of service: weblancer.net
Reference to reviews.
I have created a lot of parsers and other small scripts. Fix websites etc.

Education

2006 - 2010

Kyiv radio-mechanical college of NAU

Computer programming

Skills

PHP & Symfony

PHP, Symfony, Doctrine ORM, Twig, REST APIs, PHPUnit, ParaTest, PHPStan.

JavaScript & Frontend

JavaScript, React, TypeScript, Redux, MobX, Webpack, SCSS.

C++

C++, STL, Qt Framework.

Databases

MariaDB, MySQL, Redis, Sphinx, schema design, query optimization, indexing, normalization, denormalization.

Software Architecture

OOP, YAGNI, DRY, KISS, SOLID, GRASP, TDD, DDD, integration and API design, technical roadmaps.

DevOps & Infrastructure

Linux, Nginx, PHP-FPM, Docker, Docker Compose, Ansible, Restic, Hetzner, AWS EC2, Postfix, Dovecot, AWS SES, DMARC, DKIM, SPF, GitLab CI, Travis CI, Drone CI, Git, Mercurial, SVN, Sentry, Graylog, Grafana, Prometheus, InfluxDB, Monolog, incident triage.

APIs & Protocols and services

LMS & LTI: Canvas, Canvas SaaS LTI 2.0, Moodle, Google Classroom, Blackboard, Schoology, Brightspace, OneRoster, LTI 1.1, LTI 1.3, Names & Roles, Deep Linking, AGS, dynamic registration.
Payments: Stripe, Checkout, subscriptions, recurring invoices, promo codes, webhook signature verification, PayPal, payment-provider failover.
Auth & Security: API token authentication, OAuth2, JWT, TOTP 2FA, reCAPTCHA, encrypted-at-rest secrets, brute-force protection, GeoIP2.