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Oleksandr L.
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Oleksandr L.

Full-Stack & AI Engineer | Automation & SaaS, B2B Systems | QA (ISTQB)

I'm a Top Rated freelancer specializing in production level systems across Full-Stack, SaaS, B2B platforms, AI integrations and automation heavy applications. I build production systems that don't break under real usage and hold up under real users, real data and real business pressure. My work sits at the intersection of Full-Stack engineering, AI systems, CMS platforms and business critical integrations. I focus on building applications that are stable, scalable and actually usable in real world environments. * On the frontend I build modern web applications using #React, #Next.js, #Angular, #Laravel and #Vue.js with #Typescript, #Tailwind CSS and scalable component based architecture. I focus on #clean UI, #responsive layouts, #performance optimization, #accessibility and smooth user experience across desktop and mobile. I also work with #dashboard systems, #SaaS platforms, #real interfaces, #authentication flows and complex frontend state management. *On the backend I design and develop scalable systems using #Node.js, #Python and #Go with #PostgreSQL, #Supabase, #MongoDB and #REST/GraphQL APIs. My work includes #authentication systems, role based access control, #payment integrations, #automation workflows, #file handling, #API architecture, #database design and #cloud deployment. I focus heavily on maintainability, security, performance and building backend infrastructure that can scale without becoming difficult to manage later. * On the CMS side I work extensively with #Shopify and #WordPress including #custom theme development, #storefront customization, #Shopify Liquid, #App integrations, #WooCommerce, #Elementor, #Divi, #WPBakery and #performance optimization. I also handle #CMS migrations, #responsive redesigns, #SEO friendly structures and ongoing maintenance for production websites and eCommerce stores. * On the Automation & B2B system side I build workflow automation and integration systems that connect business tooles into unified processes. # API integrations(thrid party SaaS systems, CRMs, internal tools) # Workflow automation pipelines # Data synchronization systems # Event based automation # Scheduled jobs # Webhook orchestration # ETL-style data flows # Reporting automation and system to system communication design I specialize in reducing manual business operations by turning them into automated, reliable backend workflows. Where I bring extra value is in AI and system design. I don't just plug in APIs. I design AI features that fit into the product. # LLM integrations & LLM based workflow design for real workflows # Retrieval augemented systems and internal knowledge tools # AI driven reporting and automation pipelines # Structured, predictable outputs for business use # OpenAI API integration # Prompt-to-structured-output systems # RAG & vector database concepts I also work with SAP integrations and B2B data flows, connecting external systems, APIs and enterprise tools into a clean, reliable arhcitecture. This includes handling structured data, automations and backend logic that supports business operations. My QA background shapres everything I build. I'm ISTQB certified and experienced in both manual and automation testing using Java and Python, along with tools like Locust and Gatling for performance and load testing. *** I validate how they behave in real world conditions. This means after delivery, deployment, systems are tested with a quality focused mindset. I focus on edge cases, performance issues, API reliability and user flow stability are all considered before delivery. *** If you're building something that needs to be reliable, scalable and actually used by customers or internal teams, I can help you get it there. Regards, Oleksandr.

🇪🇸Alicante, Spain$40/hr100% JSS5.00 (6)Since Mar 2015

Earnings and projects

MRR (estimate)as of Jul 30
≈$818

An estimate from an earlier read

World#57,040 / 412k
🇪🇸Country#524 / 4,023
Revenue, last 30 days
—

Last 6 months: $4.9k

Total earnings
$51k

Billed in all: $51k

World#74,976 / 412k
🇪🇸Country#787 / 4,023
Per project
$5.7k

$1.6k in the last 6 months

World#30,578 / 412k
🇪🇸Country#305 / 4,023
Projects, last 6 months
3

Across 4 contracts

75% fixed25% hourly
World#66,479 / 412k
🇪🇸Country#598 / 4,023
Projects in all
9

Across 10 contracts

40% fixed60% hourly
World#212,268 / 412k
🇪🇸Country#1,978 / 4,023

Earnings, last 30 days

$51.2kNo reading in this rangeBilled in all by Jul 17, 2026, the last reading before this range
$50k$51k$52k$53kNo dataOct 8Oct 23Nov 7

No reading in this range. Dotted: longer than usual between two readings. Hatched: over two weeks without one.

Skill rankings: Top 12% in Golang

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