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Denis KolmykovDK

Denis Kolmykov

Software Developer

€125/day
Fréjus, FR
8-15 years

Average response time: 1 hour

About Denis

What I do:

I help founders and businesses turn ideas into working products.
My specialization is end-to-end development:

- Web applications and services: from landing pages to complex platforms.
- MVPs for startups: rapid launch to validate your hypothesis.
- Telegram bots and Mini Apps: integrating your service directly into the messenger.
- Admin dashboards: convenient internal systems to manage your project.
- Integrations: connecting payment systems, CRMs, and other third-party services.

How I work:

I’m for transparency and partnership. I explain complex technical things in plain language and stay in touch so we work as one team.
  • English

    Native or bilingual

  • French

    Basic

  • Luxembourgish

    Basic

Remote only
Primarily works remotely

Experience

  • www.fl.ru
    Fullstack-developer
    E-COMMERCE
    January 2023 - Today (3 years and 5 months)
    Fréjus, France
    Optimized database performance (MySQL, PostgreSQL, MongoDB), reducing query execution time by 20–30%. Developed complex web applications using frontend (React, Vue.js) and backend (Node.js, PHP, Python) technologies. Integrated RESTful APIs and GraphQL for client–server communication. Automated deployment processes using Docker and CI/CD tools (GitLab CI, Jenkins). Worked on high-load systems, leveraging caching (Redis) and query optimization. Delivered modular and scalable applications in line with client requirements.
    PHP Git PostgreSQL GraphQL RESTful API
  • t-bank l.tinkoff.ru/career.and.vacancies
    Lead Developer
    TECH
    November 2020 - May 2023 (2 years and 6 months)
    London, Canada
    Information Technology, Systems Integration, Internet
    - Internet company (search engines, payment systems, social networks, informational/educational and entertainment resources, website promotion, etc.)
    - Software development
    - Systems integration, automation of technological and business processes, IT consulting

    Financial sector
    - Debt collection
    - Bank

    Resume updated on May 14, 2025 at 20:52

    Lead Developer

    Training and Mentorship:
    - Organized onboarding for new employees; delivered regular training in HTML, CSS, JavaScript, PHP, Python.
    - Mentored on using Git and development tools, including Visual Studio Code and WebStorm.

    Service Standards Development:
    - Developed and implemented customer service standards, improving interaction quality and customer satisfaction.
    - Built systems to monitor key performance indicators, ensuring quality control.

    Data Analysis and Reporting:
    - Collected and analyzed data using SQL and Python; prepared analytical reports to optimize business processes.

    Customer Experience Improvement:
    - Optimized the CRM system, enabling more efficient handling of complaints and claims.
    - Developed strategies to increase customer satisfaction, leading to higher loyalty.

    Process Automation:
    - Led projects to automate customer service; implemented technologies to improve process efficiency.

    Cross-Department Coordination:
    - Collaborated with marketing, sales, and technical support to implement the company’s strategic plans.

    Development Planning and Frontend Development:
    - Planned and managed frontend projects using React, Angular, and Vue.js.
    - Ensured adherence to quality standards and on-time delivery.

    Key Achievements:
    - Developed and implemented service standards, increasing customer satisfaction by 20%.
    - Successfully led a customer service automation project, reducing request processing time by 30%.
    - Trained and mentored 20 new employees, improving team efficiency and speeding up onboarding.
    Python Git SQL React.js Angular
  • Chatroulette chatroulette.com
    Developer
    TECH
    February 2018 - October 2020 (2 years and 8 months)
    London, Canada
    Moderation and Content Control:
    - Built and maintained the backend of the moderation system to enforce platform rules using Python and Node.js.
    - Integrated filtering and blocking algorithms for unwanted content (text, images, video) with machine learning to automate workflows.

    Violation Handling:
    - Implemented automated detection and blocking of users violating platform rules through behavior analysis via APIs and blocking by IP addresses and devices.
    - Used MySQL and PostgreSQL to store user data and violation statistics.

    Conflict Prevention:
    - Developed algorithms to prevent user conflicts; implemented real-time session analysis through logging and monitoring.
    - Implemented caching of violation and request data using Redis to improve performance.

    Employee Training:
    - Organized and conducted training for new employees on platform operations, moderation technologies, and content control systems.

    Feature Development:
    - Participated in planning and developing new platform features, including improved moderation and integration with external services to enhance quality.
    - Designed and implemented RESTful APIs for interaction with the frontend.

    Security and Improvements:
    - Prepared regular reports on task execution and identified security threats; proposed system enhancements.
    - Collaborated with the security team to identify vulnerabilities and minimize risks using tools such as Wireshark and Burp Suite.

    Achievements:
    - Implemented a moderation system, reducing complaints about unwanted content by 30%.
    - Optimized the user blocking process, increasing violation processing speed by 40%.
    - Trained and onboarded 5 new employees, accelerating their integration into workflows.

    Key Technologies and Tools:
    - Backend: Python, Node.js
    - Databases: MySQL, PostgreSQL, Redis
    - API: RESTful API
    - Analysis Tools: Wireshark, Burp Suite
    - Moderation and Automation: machine learning, logging, monitoring
    Python PostgreSQL JavaScript RESTful API Wireshark

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Education

  • Bachelor
    Don State Technical University
    2023
    Bachelor
  • Full course on Web development (Full Stack Web Development)
    Netology, Full-stack development
    2021
    Full course on Web development (Full Stack Web Development)

Skill set

Categories