Daniil O.

Full-Stack Engineer | Astro, React, Node, Python | Production-Ready

On my last Upwork contract I took a client's website from a 69 mobile PageSpeed score to 99, and from 16-second loads to under 2 seconds. Here's what he wrote in his 5.0 review: "He kept finding and fixing problems I didn't even know we had, like hosting compliance issues and DNS conflicts during the migration, and he always came with the solution already worked out and clearly explained. The results are real: our mobile speed score went from 69 to 99 and the site now loads in under 2 seconds instead of 16." The full case study is in my portfolio below. What I do: - Site speed and Core Web Vitals rescue. I audit, fix, and hand you verified before/after numbers (PageSpeed, Lighthouse, real load times). - Site migrations that don't break things: hosting, DNS, CMS moves, framework upgrades. - Full-stack product work in TypeScript: React, Next.js, Astro, Node.js, PostgreSQL, Strapi and other headless CMSs. Auth, payments (Stripe), dashboards, CI/CD. - AI features when you need them (RAG, structured extraction), built with cost control in mind. How I work: clearly scoped milestones, a structured update after every working session, and everything set up under your own accounts with documentation, so you own your infrastructure completely. That last part is straight from my client's review. Before Upwork I was a founding engineer at Quextro (an AI platform for teachers, built solo front to back) and spent ~8 months at Radency, a UK PropTech serving local councils. Not a fit for: pure design work, Shopify theme customization, or deep WordPress plugin development. Send me your URL or your brief and I'll come back with a concrete plan, usually the same day.