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I help founders and small teams turn messy workflows, fragile automations, spreadsheets, and AI-built prototypes into reliable web and mobile apps that are ready for production use. I’m a full-stack no/low-code architect with 18+ years of IT experience. I work at the intersection of product, data architecture, automation, and implementation: I clarify the workflow, choose the right stack, build the system, explain trade-offs, and help prevent expensive structural mistakes. 𝐖𝐇𝐄𝐍 𝐈’𝐌 𝐀 𝐆𝐎𝐎𝐃 𝐅𝐈𝐓 • Scale & Stability: Your current Airtable, Bubble, Glide, Lovable, Claude/Cursor, or AI-generated setup is becoming fragile, messy, or hard to maintain. • Production Systems: You need a SaaS MVP, client portal, internal tool, mobile companion app, CRM/workflow automation, or AI-powered product that must be stable, maintainable, and ready for daily operations. • Fractional CTO / Technical Partner: You need someone to own the architecture, document the system, coordinate developers/vendors, and guide technical decisions beyond pure development. ⚠️ 𝗡𝗼𝘁 𝗮 𝗳𝗶𝘁: I’m not the best fit for cheap one-off fixes or pure task execution. 𝐓𝐄𝐂𝐇𝐍𝐈𝐂𝐀𝐋 𝐒𝐓𝐀𝐂𝐊 🧱 𝗣𝗿𝗶𝗺𝗮𝗿𝘆 𝗦𝘁𝗮𝗰𝗸: WeWeb + Supabase + n8n for serious web apps, SaaS products, internal tools, and automation-heavy systems. 📲 𝗠𝗼𝗯𝗶𝗹𝗲 𝗙𝗿𝗼𝗻𝘁𝗲𝗻𝗱: FlutterFlow as a mobile frontend connected to the same backend and automation layer. 🧰 𝗔𝗹𝘁𝗲𝗿𝗻𝗮𝘁𝗶𝘃𝗲 𝗦𝘁𝗮𝗰𝗸: Bubble, Xano, Glide, Softr, Airtable, Make, Zapier, Webflow, Figma, Docker. 🛠️ 𝗖𝗼𝗱𝗲 & 𝗔𝗜: Vue.js, JavaScript, Python, SQL, APIs, Claude Code, Cursor, Codex, Lovable. 𝐃𝐄𝐄𝐏 𝐖𝐄𝐖𝐄𝐁 & 𝐒𝐔𝐏𝐀𝐁𝐀𝐒𝐄 𝐄𝐗𝐏𝐄𝐑𝐓𝐈𝐒𝐄 I go beyond standard no-code assembly. I build custom Vue.js components, manage complex frontend states, design clean frontend/backend boundaries, and structure backends with PostgreSQL, RLS, auth, Edge Functions, SQL workflows, and disciplined SQL versioning. I fix projects where typical no-code or AI-built systems start to break. 𝐓𝐘𝐏𝐈𝐂𝐀𝐋 𝐄𝐍𝐆𝐀𝐆𝐄𝐌𝐄𝐍𝐓𝐒 • Apps & Portals: Web apps, SaaS MVPs, client portals, internal tools, and mobile companion apps. • Infrastructure Cleanup: Stabilizing and refactoring rushed AI-built, low-code, or spreadsheet-based products. • Automations & Backends: n8n/Make/Zapier workflows, secure Supabase databases, CRM integrations, webhooks, and API-based systems. • Tech Leadership: Fractional CTO support, architecture reviews, product/technical trade-offs, documentation, and handoff. 𝐄𝐍𝐆𝐀𝐆𝐄𝐌𝐄𝐍𝐓 𝐌𝐎𝐃𝐄𝐋 I bring the most value to business-critical, messy, or fast-growing projects that need architecture before implementation. Clients work with me because I can both build and advise — and because I’m comfortable calling out shortcuts that may look cheap now but become expensive later.

I find Upwork to be a wonderful place where fundamental things such as hard work, dedication, organization skills, persistence, and honesty are cherished the most. I was persistent enough to dedicate myself to this platform and it resulted with providing me with new business experiences and skills and gave me an opportunity to meet new people and cooperate with them. So far, this journey has led me to become a Top-rated Upwork freelancer and I couldn't be more grateful that my hard work and dedication were recognized by this platform and community. I believe I can easily spend as much time as needed to hand over the project to your satisfaction before any deadline to have enough time for any modifications if needed, of course. I have the CAE (Cambridge Assessment English) C1 diploma, so my not being a native speaker is definitely not an issue. My previously completed Data Entry projects provided me with excellent practice and knowledge, and all of my previous clients would say the same. I have excellent knowledge of the following: ★ Microsoft Office with advanced skills in Word and Excel ★ Google: Docs and Sheets. ★ Data Entry, Data Management, Data Organization, Data Analysis, PDF to Excel ★ Internet Research, Product Research, Company / Contact Research ★ Database Administration, Database Reporting. ★ Logo Creation, Graphic Design In addition to that, I have developed incredible interpersonal skills, attention to detail, multi-tasking ability, and an incredible work ethic. I'm trying to become a trusted freelancer and I'm trying to showcase that working with me is extremely easy since I'm a very easy-going, responsible, and very reliable person. I have the enormous motivation to work. My main plan is to maintain that mindset towards all of my clients. Go ahead and take a look at some of the comments my clients had posted about me. ★ "I like how he chatted with me to know if he is doing the job right. He checked in and ensured his work was efficient and quality was his highest concern. Very happy with the work he completed." ★ ''Luka is an excellent data entry and SEO contractor, I will be happy to use his services again in the future, thank you" ★ "I am glad to have worked with Luka, he has been very transparent, attentive, and communicative in achieving the requirements of this task." ★ "Great to work with, positive approach, a go-to guy for any project you require. Highly recommending Luka!" ★ "Very responsible and skilled freelancer hired the second time and will work with you again." ★ "Luka is an amazing freelancer, always replies quickly and delivers quality work very quickly. I would highly recommend working with him." ★ "Luka was great, good comms hard working. We will work with him again !!" ★ "Luka did a great job. He submitted a detailed and very useful for my report at the end. Would recommend." ★ "It´s such a pleasure to find a hard-working, talented and reliable young person. When this happens and they give more than you expect, you can only appreciate having the opportunity to work together. Luka has very good Word document editing skills and an eye for detail. But on top of that he has an attitude and that´s really something valuable. I´ll be more than willing to work with him again. Thank you, Luka!" ★ "Luka was a great partner to work with on building out my website. He was extremely communicative, detail-oriented, and incorporated feedback quickly. The task look a bit longer than expected, but in pursuit of a high-quality finished product. Would definitely recommend Luka for your project!" ★ "Excellent worker; I would say the task was completed with 98%+ accuracy. Communication was phenomenal, and Luka asked fantastic follow-up questions to ensure clarity of the assignment. I would highly recommend Luka." ★ "I couldn't have imagined a better support for this job. The effort Luka has put into this job went beyond all expectations. I really can recommend Luka and his work to everyone seeking for a good and reliable Freelancer." This was a part of my profile description a year ago. ''I have 2 goals on this platform and will do my best to achieve both of these goals in the 1-year timeframe. 1★) I want to become a trusted Upwork specialist who will be well respected in this community/platform. 2★) I don't want to have a single bad review because I want to continue giving my honest time and effort to every single client. Real Talk! I plan to have this same mindset and the same approach to every single client.'' - so far, so good. I am flexible regarding the terms and conditions of my work. Clients will find out that negotiating the price of a project with me is extremely easy. I care about my client's satisfaction more than about the price of the project, so I promise that I will triple-check everything and edit anything if needed. Do not hesitate to click that green ★INVITE★ button, so we can chat about your project in a more detailed manner. Kindest regards, Luka Jevric

I am a Human Resource Specialist with 4 years of experience, having worked with start-ups, and large companies from Israel, USA, UAE, and Europe. I have a background in law (Bachelor's degree). With a focus on labor law. Also, proven experience in Recruiting for Technical and Non-Technical roles. I'm from South-Eastern Europe, an area with a lot of talent. So I can provide you with an excellent database of candidates from this region.

Web developer since 2016: - Started as a backend developer. - Improve my work with frontend skills during 2017. - Started with WebGL Three.js programming in 2017. I love to work on WebGL projects because it enhances my creativity as well as logic. I firmly believe that websites will become more attractive with 3D objects that can represent client's work in the best way and can make all that boring presentations more live. If you choose me, you will always get an error-free, responsive website or web application delivered on time, I am a full-time freelancer, and you can contact me anytime!

💯 100% Job Client Satisfaction 🏆 Top Rated Freelancer 🎯 Certified Developer 💎 What I Bring to Your Project 💎 🔹 Precision in creating pixel-perfect, responsive designs 🔹 Custom coded websites using HTML, CSS, JS & PHP 🔹 In-depth knowledge of the security best practices 🔹 Ability to quickly diagnose & fix performance issues 🔹 24/7 reliable communication: you'll always be informed about the project's progress 🔹 A partner who genuinely cares about your success and delivering value to your business 💎 Why Choose Me Over Other Freelancers 💎 🔹 Client Trust: I’m dedicated to providing value and building lasting TRUST 🔹 Exceeding Expectations: Over-delivering is at the heart of my freelance work. I aim to go above and beyond, leaving clients with that "WOW" feeling every time 🔹 Clear Communication: I’m HIGHLY RESPONSIVE, keeping communication open and transparent throughout the entire project. 🔹 Kindness & Respect: I believe in treating everyone with kindness, empathy, and respect, and I carry this approach into every interaction, always striving to improve your experience and outcomes 💎 Testimonials from high-profile Clients 💎 The feedback highlighted below, along with those in my work history, showcases the high level of quality and value you can expect when collaborating with me. 🌟🌟🌟🌟🌟 "Stefan is a creative genius! His skill and knowledge makes me wonder if he is a Super Hero in disguise. He completed the total build of my Plants vs Humans website in just weeks. Everything was more than perfect. The site had a tight timeline for completion and this fellow NAILED IT! My concern is that if a lot of people tap his talents and realize his mastery - I hope he has time to work on my other projects" - Robert 🌟🌟🌟🌟🌟 "I am happy with all the help that Stefan provided to me. He clearly understood all the requirements and created the 1st draft of the website in just 1 day. All further iterations were completed in time and with a good quality of work. Stefan was always very responsive, made many adjustments within the same budget and provided me a lot of advice related to design" - Eugenia 🌟🌟🌟🌟🌟 "I recently had the opportunity to work with Stefan on a web development project and I have to say, I was thoroughly impressed by his skills and professionalism. From the very beginning, it was evident that Stefan was knowledgeable and experienced in the field, and he was able to cater to my specific needs and bring my vision to life. Throughout the project, he was an excellent communicator, keeping me informed every step of the way and promptly addressing any questions or concerns I had." - Yawar

✅ Professional Penetration Tester ✅ 3500+ Hours ✅ Top Rated Plus Freelancer Security Researcher and Penetration Tester recognized by the U.S. Department of Defense, AT&T, Sony, and Semrush for the responsible disclosure of 40+ vulnerabilities via HackerOne. Since 2022, an active member of the Synack Red Team - an elite tier of offensive security specialists vetted through rigorous technical and background screening. Every engagement concludes with a comprehensive technical report built to satisfy the specific penetration testing controls required for HIPAA, ISO 27001, SOC2, and PCI-DSS. I provide a high-level executive summary for stakeholders alongside deep-dive technical findings, fully reproducible Proofs-of-Concept (PoCs), and prioritized remediation steps to ensure your team can effectively close every gap before your audit. Specializing in black and gray box testing of live web applications, cloud environments, and networks, covering all common attack vectors, business logic flaws, and discovering previously undisclosed vulnerabilities (0days) to prevent high-impact data breaches. Service Description: 1) Web Application Penetration Testing (OWASP Top 10, PTES, ASVS, Business Logic Testing) 2) Mobile Application Penetration Testing (OWASP Top 10, MASVS, MASTG, PTES) 3) Network Penetration Testing (Active Directory, Entra ID, Internal & External Network) 4) API Security Testing - REST, GraphQL, SOAP, gRPC, Webhooks (OWASP API Top 10) 5) Cloud Security Testing - AWS/Azure/GCP/OCI/Alibaba/IBM/DigitalOcean/SaaS/IaaS/PaaS 6) Cloud-Native & Container Security (Kubernetes, Docker, OpenShift, EKS/AKS/GKE) 7) LLM Security Testing (OWASP LLM Top 10, Prompt Injection, Data Poisoning) Tools used in engagements: BurpSuite Professional | Custom Python scripts | BloodHound | Impacket Framework | Responder | Metasploit | Mimikatz | Nuclei | Nmap | FRIDA | Android Studio | Pacu | Prowler | Postman Identify and secure your attack surface before threat actors do ! Message me to discuss your project requirements.