Karine Y.

FULL-STACK ENGINEER | WEB, MOBILE, BACKEND, AI INTEGRATION I build software end to end, and I'm not tied to one language or platform. A web platform, an iOS app, an Android app, a backend API, an AI-powered feature, or all of them working as a single system. You describe the product; I select the right technology and deliver it. 7+ years of full ownership, from architecture through deployment. I don't start from a stack; I start from your requirements. The product decides the technology, so you never pay for workarounds later. WHAT I BUILD Web: customer-facing platforms, SaaS products, e-commerce, dashboards, admin panels, internal tools Mobile: native iOS, native Android, or one cross-platform codebase covering both Backend & APIs: REST and GraphQL services, real-time systems, authentication, third-party integrations Data: relational and NoSQL databases, schema design, migrations, query optimization, reporting Infrastructure: server configuration, cloud or dedicated deployment, CI/CD, monitoring, scaling Design to code: Figma, Adobe XD, and wireframes turned into production interfaces AI INTEGRATION I add AI to existing products and build new products around it: Custom chatbots and assistants trained on your documents, catalog, or knowledge base (RAG) LLM integration into existing applications: OpenAI, Anthropic, and open-source models AI agents and workflow automation that replace repetitive manual operations Document processing: extraction, classification, and summarization at scale Speech-to-text, translation, and content generation pipelines Search and recommendations that understand intent, not just keywords Every integration is built for production: cost control, rate limiting, error handling, and predictable behavior, not a demo that breaks under real usage. PAYMENTS, DELIVERY & COMPLEX INTEGRATIONS Payments: Stripe, PayPal, and regional gateways; subscriptions and recurring billing, marketplace split payments, multi-currency, refunds, webhooks, reconciliation Delivery & logistics: carrier API integration, live rate calculation, label generation, real-time order tracking, delivery zones, driver and dispatch apps Anything with an API: CRM, ERP, accounting, SMS and email providers, maps, analytics, legacy systems These are the parts of a project where things quietly go wrong months after launch. I build them to be traceable, testable, and safe to change. LANGUAGES & STACKS PHP (Laravel), JavaScript and TypeScript (React, Vue, Node.js), Python, Java, Kotlin, Swift, C#, Go, and Dart/Flutter. I pick up an unfamiliar stack quickly when a project calls for it. If your product runs on something not listed here, ask; the answer is usually yes. HOW I WORK Scope before code: we define what "done" means in writing before development starts Regular demos: you see working software throughout the project, not a status report at the end Clean handover: documented code, environment setup, and a walkthrough; you are never locked in Direct communication: clear updates, reliable timezone overlap, no silent stretches Whether you need a single feature, a full product built from zero, a rescue of an existing codebase, or long-term development alongside your team, the value is the same: one engineer covering the entire product, no handoffs between separate teams, and no gaps where handoffs usually fail. Tell me what you're building and where it stands today. I'll reply with an honest assessment of scope, timeline, and the approach I'd recommend, before you commit to anything.