Curriculum vitae / full version

Bogdan
Teslenko

Senior Frontend Developer, Larnaca, Cyprus

I build the frontends where the hard part is not the screen you see, but the state and the messy data behind it. Architecture, complex applications, and code that stays maintainable after the third change of requirements.

Profile

Senior frontend developer, currently the most senior frontend engineer on my team and the person who owns frontend architecture decisions. I work mainly with Angular and Vue.

The work I like sits where the domain is complicated: production equipment tied into drug manufacturing, tariff catalogues from telecom carriers that never agree on a data shape, geological data that needs structure before anyone can use it. The pattern across all of it is the same. Take input nobody designed for you, make it reliable, keep the codebase readable for whoever comes next.

Experience

Software Engineer, GRSE

Sep 2020 - present
Custom software for clients in the German market

I work across several Scrum teams on the frontend side. Over time I became the team's most senior frontend developer, and frontend architecture decisions are mine to make. Two projects have taken most of these years.

Equipment-management module for pharmaceutical production
Angular / cross-functional team of 5
  • Built the module from scratch for a browser-based manufacturing platform, on the frontend side of a team of five (2 frontend, 2 backend, QA).
  • Implemented the full equipment lifecycle and tied it into the production process. Not a list of machines, but equipment linked to drug manufacturing from planning through completion, accounting for wear and for mandatory procedures such as cleaning and washing.
  • Managed application state with RxJS and Angular Signals.
  • Worked on top of the company's internal UI framework, extending and fixing it alongside feature work.
AngularRxJSAngular SignalsTypeScript
White-label e-commerce platform
Vue 3 / 3-person frontend team
  • Built the platform from scratch in a team of three frontend developers. One Vue 3 codebase powers 20+ partner shops, each with its own branding, content and language, selling mobile and landline tariffs from major German carriers.
  • Built the configurable cart, which combines tariffs, options, hardware and incentives. This was the hardest part of the project, and the reason was the carriers themselves: inconsistent, non-standard data models that had to be normalized before anything could be composed reliably.
  • Integrated carrier APIs on the frontend, including address availability checks and product recommendations that decide which tariffs a customer is shown.
  • Added multilingual support so the same shop runs in several languages per partner.
  • Improved accessibility and frontend performance across the shops.
Vue 3PiniaRxJSTypeScriptRESTWebSocketsJestCypress
  • Across both projects: migrated an earlier codebase from plain JavaScript to TypeScript to make it maintainable.

Mentor, JavaScript Course, HTML Academy

Aug 2021 - Feb 2022, part-time
Alongside the work at GRSE
  • Mentored three semesters of students, from zero to writing JavaScript confidently.
  • Reviewed student code regularly and gave concrete feedback that showed up in the quality of their projects.
JavaScriptCode reviewMentoring

Frontend Engineer, Gazprom

2019 - 2020
Internal development team building tools for the company's own needs
  • Built the full technical implementation of a system that predicts problems during well drilling, in TensorFlow and Python, working directly with a geologist who handled the data and its interpretation. The project won an internal competition among the company's subsidiaries.
  • Created a system for systematizing and processing geological data. It sped up the work of the department that relied on it several times over.
  • Delivered 10+ smaller internal projects across a wide range of stacks: geological systems in Angular, a PWA in Vue, a Jira-board analogue in React, and internal tooling that made the team's own work easier.
AngularVueReactPythonNode.jsTensorFlow

Information Security Specialist, Gazprom

2015 - 2019
Information security work, with frontend side projects running in parallel

Junior Frontend Developer, Echo

2013 - 2015
Small local web studio
  • Turned design mockups into working websites on CMS platforms.
  • Built the studio's own business website.
HTML5CSS3MODXWordPress

Side projects

  • A Telegram bot that lets 1000+ users share music across different sources and platforms.
  • A cross-platform mobile app for learning Greek grammar.
  • Several other pet projects across a range of technologies, which is where most of the stack below came from.
Node.jsTypeScriptPythonAngularReactFlutterDartSQLiteTypeORM