Олег

OLEH KRYVKO
Senior Full-Stack Engineer — PHP / Laravel · TypeScript / React
Constanța, Romania · EU resident (temporary protection, full right to work, no sponsorship needed) · Remote, CET+1 · Available now
[open contact info](look above in the "contact info" section) · [open contact info](look above in the "contact info" section) · Telegram: @okdev · [open contact info](look above in the "contact info" section)

S U M M A RY
Full-stack engineer with 10 years of commercial experience — 7 of them focused on backend architecture in PHP / Laravel, and a
modern frontend practice in TypeScript, React and Next.js. I build the parts of a product that must not fail: billing and subscription
engines, high-load marketplaces, fintech microservices and reservation-style concurrency logic. Most recently I shipped a complete
product single-handedly in TypeScript / Next.js 15 — from first commit to paying customers in three weeks.
AI-assisted engineering: Claude Code as a daily driver (Anthropic Academy: Claude Code 101, Claude 101). I run agent-driven
workflows for feature delivery, large refactors, test coverage and code review — which measurably shortens delivery cycles. I also
integrate LLM/AI services (Anthropic, OpenAI, Azure Speech, ElevenLabs, D-ID, HeyGen) into production products.

TECHNICAL SKILLS

Backend PHP 8.1–8.4 (since 5.6), Laravel 8–12, Filament, Yii 2, PHPUnit, OOP, SOLID
Frontend TypeScript, React 19, Next.js 15 (App Router / RSC), Vue, JavaScript, HTML5, CSS / SCSS, Vitest,
Playwright
APIs & Architecture REST, JSON:API, gRPC, microservices, RabbitMQ, OAuth 2.0, webhooks, event-driven design
Databases MySQL / MariaDB, PostgreSQL, Redis, Memcached, MongoDB; query & index optimisation
Infrastructure Docker, AWS ECS, GitHub Actions, GitLab CI, Caddy, Linux, ffmpeg, Jira
AI & Automation Claude Code (Anthropic Academy courses), Anthropic API, OpenAI API, Azure Speech (TTS),
ElevenLabs, D-ID, HeyGen, Telegram Bot API, Google APIs
Analytics & CRM PostHog, Matomo, HubSpot Forms API, Facebook Graph API

EXPERIENCE
Solo Full-Stack Engineer — AI photo-to-figurine product for live events 2026 · contract
Remote · client contract, US market · TypeScript, Next.js 15, React 19, PostgreSQL (raw SQL, no ORM), Docker + Caddy on a self-hosted
VPS, GitHub Actions, OpenAI Images API
Sole engineer across product, infrastructure and operations — iPad-kiosk capture → AI caricature generation → private
mobile approval with e-signed release → print-and-cut pipeline. Paying events within 3 weeks of the first commit.
Reservation-style concurrency without a queue: photo-to-guest binding as a single conditional UPDATE … RETURNING +
dependent INSERT , so a double-tap or a second kiosk gets a clean 409; confirmation is one transaction where a failed email
rolls back the claim.
Frontend in TypeScript end-to-end: Server Components by default, typed API error contracts shared between server and
client, guest screens designed for one-handed outdoor use; Vitest + Playwright on critical flows (103 automated tests).
Delivery & ops: migrated Vercel + Supabase → self-hosted Docker/Caddy VPS; CI to GHCR with a deploy gate that waits for
zero in-flight jobs; nightly restic backups with rehearsed restore.

Backend Developer — Pitch Avatar @ ROI4CIO 05.2025 – 07.2026
Remote · SaaS for interactive video presentations with AI avatars · PHP 8.1 / Laravel 9 (JSON:API) monolith inside a microservice
environment — gRPC, Redis, MariaDB, Docker, AWS ECS · ~350 commits
Billing & subscriptions (owned end-to-end): seat-only checkout, volume-tiered listener billing, seat limits, multi-currency
handling, recurring payments.
Integration resilience: retry / timeout / backoff layer hardening all external API calls; multi-provider AI integrations (D-ID,
HeyGen, Azure Speech, ElevenLabs) with multilingual SSML output.
Core platform: JSON:API resources, complex filtering and sorting, dependency validation, dual-database migrations (main +
logs), PHPUnit coverage.
Analytics pipeline: streamed domain event logs into PostHog through a dedicated gRPC Event Gateway, instrumenting dozens
of domain actions.
Media processing: PDF and PowerPoint parsing, font import, per-slide transitions; improved exported video quality by tuning
ffmpeg (preset, CRF, audio filters).
CRM & marketing: UTM passthrough into HubSpot (Forms API); OAuth sign-up / login via Facebook Graph API.

Senior PHP Full-Stack Developer — AirAdvisor 09.2024 – 04.2025
Delaware, USA · Remote · Flight-compensation platform (airadvisor.com)
Data integration and API processing over aviation feeds — OAG and Spire APIs, Redis, MySQL, Laravel.
Backend scaling and optimisation with asynchronous processing via RabbitMQ.
Monitoring, reporting and system-performance improvements.

Senior PHP Full-Stack Developer — Nova Poshta 03.2023 – 07.2024
Kyiv, Ukraine · Remote · High-load marketplace (np.shopping)
Maintenance and development of a high-load marketplace (Laravel, jQuery).
Application architecture and new frontend modules (React, HTML, CSS).

Senior PHP Full-Stack Developer — BTCbit 11.2021 – 01.2023
Riga, Latvia · btcbit.net · Crypto exchange / fintech
Microservices development — PHP 8.1, Laravel 8, Vue, Sass, Docker.
Led the migration from PHP 7.4 to PHP 8.1 across the platform.
Optimised inbound REST API processing (CodeIgniter 3).

Senior PHP Full-Stack Developer — Concepta 05.2021 – 10.2021
Larnaca, Cyprus
Automation of routine business processes (PHP, Laravel, JS, SQL, Amazon API, Google API).
Google Chrome extension development. Team lead of 3 engineers.

Full-Stack Developer — Nadavi (ek.ua) 01.2019 – 04.2021
Kyiv, Ukraine · Price-comparison platform
Delivered new functionality and design updates (JS, jQuery, Ajax, HTML, CSS, Bootstrap, Gulp, PHP).

PHP Developer — TrustSourcing 09.2016 – 11.2018
Kyiv, Ukraine · trustsourcing.com
Gaming platform development (Yii 2, MySQL, MongoDB, Redis); new features, refactoring and CMS functionality (PHP, Yii, REST
API).
Performance optimisation across 11 production websites (PHP, jQuery, Ajax).

C E R T I F I C AT I O N S LANGUAGES
Claude Code 101 — Anthropic, Jul 2026 · ID zx8s29idd28c Ukrainian — native
Claude 101 — Anthropic, Jul 2026 · ID eaixtmffroex English — B1, intermediate (working proficiency; written
stronger)
Russian — fluent

E D U C AT I O N
Dnipro University of Technology — Faculty of Information Technology, Development and Software Testing of Computer Systems,
2006–2012 (formerly National Mining University, Dnipropetrovsk).
Additional: Magento programming (magedoc.net) · SEO & Internet Marketing (seotech.com.ua) · Manual QA (portnov.com)