ΛNΛLOG — A minimal analytics tool to self-host.

2025 Jun. Full-Stack Developer.

bbox.l.r — A promotional website for Aphex Twin.

2023 May. Front-End Developer.

Battle of Cards — A rogue-like card game.

2018 Jul. Front-End Developer, UX Designer.

SËCU — Share encrypted data that is destroyed upon receipt.

2016 Mar. Front-End Developer, UX Designer.

IX — An XMPP client based on Strophe and Ionic.

2014 Nov – 2015 Jan. Front-End Developer.

Front-End

AJAX, Angualr JS, Axios, CSS, D3.js, Drizzle ORM, Express, Git, GraphQL, Gulp, HTML, Ionic, JavaScript, Jest, jQuery, jQuery UI, JSS, JSX, LESS, Mercurial, MongoDB, Next.js, Node.js, Paper.js, Playwright, PostgreSQL, Preact, Radix UI, Ractive.js, React, React Native, Redis, Redux, Redux-Saga, REST, Rollup, SASS, Satori, SCSS, Server-Sent Events, Svelte, SvelteKit, Three.js, TypeScript, Vike, Vite, Vitest, Webpack, WebRTC, WebSocket, XMPP

Graphics

Adobe Creative Suite, Affinity Designer, Blender, SketchUp

Senior Front-End Engineer, 2024 Apr – 2025 Dec

• Helped to develop a feature-rich agentic AI experience, using TypeScript, Next.js and Tailwind
• Led the development of the chat, customised rich text editor and document viewer
• Implemented spreadsheet view for structured data using AG Grid
• Used Astro to cut loading times and improve the landing page performance
• Added Weblflow and headless CMS integrations to allow non-technical people to publish content independently
• Developed and maintained a library of reusable components based on the Radix UI primitives

Instill AI, London, UK. AI automated workflows for data structuring.

Front-End Engineer, 2022 May – 2024 Apr

• Improved the app performance and loading times by ~50% by optimising assets and using code splitting
• Fixed the OAuth integration implementing proper token rotation
• Created numerous rich CSS and SVG animations as part of the user experience gamification
• Maintained numerous custom AWS hosted widgets, which were generated on the server side via edge functions
• Added multiple Web3 network integrations

Quira, London, UK. Code competitions sponsored by big brands.

Front-End Consultant, 2018 Nov – 2025 Jul

• Led the development of a dashboard to manage augmented reality experiences, using TypeScript, React and Next.js. Implemented preview for audios, videos, video streams and 3d models. Integrated OAuth via the Apple account, with Redis layer to improve token rotation
• Moved the company's old website to a modern tech stack and added a complete online store flow with Shopify
• Created and maintained a library of reusable React components
• Helped with execution of various experimental interactive projects using different browser media APIs

KALKUL, Tokyo, JP. Digital laboratory.

Senior Front-End Developer, 2019 Mar – 2021 Mar

• Created and maintained a library of reusable components closely working with the designer
• Using TypeScript, React and Next.js implemented user flows based on Figma designs
• As part of the product, I helped to develop and maintain the company's Chrome extension with numerous support chat integrations

HumanFirst, Montréal, CA. A tool to create and manage instructions for AI-native apps & workflows.

Front-End Developer, 2018 Nov – 2019 Apr

• Developed a number of React Native cross-platform mobile applications

Brocoders, Sumy, UA. Digital agency.

Front-End Developer, 2018 Jun – 2018 Nov

• Led the front-end development mastering React
• Implemented and maintained pixel-perfect responsive user interface

misterporter, Amsterdam, NL. Technology-driven automated Airbnb management tool.

Front-End Consultant, 2016 Nov – 2017 Feb

• Developed an interactive resolution-agnostic graphics-rich case study with a lot of animations using Vanilla JavaScript. Also optimised it for better performance and search discovery.
• Created a number of high-performance interactive experiences

Fueled, London, UK. Digital agency.

UI Developer, 2015 May – 2016 Aug

• Built the company's brand on the initial stage
• Used Three.js to bring to life the brand visuals for the company's website
• Led the design and front-end development of all the company's projects

TypeDB, London, UK. The AI-native database for intelligent systems.

Front-End Developer, 2012 Oct – 2015 Mar

• Developed and maintained a large production code base with thousands of daily visitors
• Worked closely with the designers, implementing new user flows and maintaining the design system
• Released a cross-platform mobile application using Ionic framework
• Leading the front-end development helped with the company's different side-projects and experiments

Pravoved, Saint-Petersburg, RU. Legal tech company.

Front-End Developer, 2011 Nov – 2012 Sep

• Developed and maintained WordPress websites and plugins for numerous clients

Domprog, Saint-Petersburg, RU. A software development company.

Front-End Developer, 2010 Sep – 2011 Aug

• Led the website front-end development and maintenance for clients

Data Star Systems, Murmansk, RU. A digital agency.

Web Designer, 2010 Jun – 2010 Sep

• Created a number of user flows and design systems

CubeLine Agency, Saint-Petersburg, RU. A marketing agency.

Content Manager, 2007 Oct – 2008 May

• Managed numerous WordPress websites for local companies

MASCH Software Solutions, Saint-Petersburg, RU. Software development and distribution company.

Rodrigo Mendoza-Smith, Quira

Alexander possesses a rare blend of technical ability and design sensibility. During his tenure with us he delivered pixel-perfect implementations of designs and consistently strived to create highly optimised code. Alexander is an extremely creative individual that routinely collaborated with our product and design teams to iterate on designs and improve the user experience of the product. He worked so efficiently that he often had spare capacity during sprints to take on more engineering tickets.

Gregory Whiteside, HumanFirst

In his role, Alexander was deeply involved in the front-end development of the HumanFirst Studio, the web application part of our product. He was working closely with our designers bringing consistency to the user experience, making the Studio an easy to understand and easy to use application. Our product benefited greatly from Alexander's technical skills and his keen eye for detail.

Bartek Kołacz, KALKUL

I highly recommend Alexandr Petcoglo for any role needing expert front-end development and a sharp eye for design. Alexandr stood out during his time with us, especially with his work on a complex AR app, showcasing his mix of technical skill, innovation, and aesthetic sense. His ability to blend functionality with beauty improved our projects noticeably. Beyond his technical and design talents, Alexandr's teamwork and professionalism made him invaluable. I'm looking forward to future collaborations.

Haikal Pribadi, TypeDB

Alexander, or Sasha as we call him, is one of the most efficient engineers that I have worked with. Sasha has a great discipline, with delivering tasks that he has planned in a timely manner, with a well-estimated work plan. The dedication towards the quality of his work is something that any team member would appreciate from Sasha, as well as his independence in achieving them. Sasha has a very decisive attitude in which you can rely on, which will drive the development with a strong sense of initiative. On top of his engineering skills, Sasha has a great sense of design, together with a touch of humour in the design work that he produces which I have found to enjoy. I have no reservation that Sasha would bring a substantial contribution to your team and I would be happy to give further information regarding his work through direct correspondence. Please liaise with Sasha to obtain my contact details.