Andrey contributed to both the sveltejs/svelte and zed-industries/zed repositories, focusing on targeted improvements in CSS and TypeScript tooling. In Svelte, Andrey addressed a nuanced bug in CSS animation scoping by introducing a helper to detect global block context, ensuring keyframes inside global CSS blocks remained properly scoped and preventing unintended animation prefixing. This work, implemented with CSS and compiler development skills, improved styling predictability and maintained backward compatibility. In Zed, Andrey enhanced TypeScript linting by integrating TypeScript file support into the ESLint flat configuration, streamlining configuration management and reducing manual setup for TypeScript projects using Rust and TypeScript.