You will get Experienced Back-End API Developer for Your Project Needs
Project details
Are you looking for a backend developer for your Mobile Application or Web Platform? Then I am the right person for the job.
Responsibilities:
Design and develop backend APIs for web and mobile applications
Integrate APIs with third-party services and APIs
Ensure the scalability and efficiency of the APIs to handle a large number of users and transactions
Test and document APIs for ease of use and maintenance
Provide ongoing maintenance and support for APIs
Please contact me with your project requirements and we can discuss the details further.
Responsibilities:
Design and develop backend APIs for web and mobile applications
Integrate APIs with third-party services and APIs
Ensure the scalability and efficiency of the APIs to handle a large number of users and transactions
Test and document APIs for ease of use and maintenance
Provide ongoing maintenance and support for APIs
Please contact me with your project requirements and we can discuss the details further.
Programming Languages
HTML & CSS, JavaScript, PythonCoding Expertise
Cross Browser & Device Compatibility, Performance Optimization, DesignWhat's included $799
These options are included with the project scope.
$799
- Delivery Time 9 days
- Number of Revisions 3
- Number of Pages 10
- Source Code
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Tim F.
Mar 25, 2024
iOS Store ready casino app
DB
Daria B.
Dec 13, 2021
[COM] Senior Frontend Developer (React JS) needed for prototype building and further development
Kristijan is definitely a knowledgable Senior-level developer who has extensive experience in React JS. We enjoyed working with Kristijan as he helped us solve tons of tasks in a timely and accurate manner. We recommend Kristijan for hiring, and wish him huge success in the next projects he'll be working on.
CB
Callan B.
Nov 16, 2021
React Web Developer with Strong Data Architecture Experience Needed
Kristijan, in addition to being an all around fantastic developer, has an abundance of patience and problem solving skills. Complex bugs or ideas are looked at systematically.
CB
Callan B.
Oct 19, 2021
Full Stack Engineer - Customer Facing Portal Development
Clear concise work coupled with the agility to change to new tasks quickly.
AK
Anna K.
Jun 14, 2021
Experienced React Native Developer for web and mobile
Great developer. We had a project with very tight dealines. Not only Kristjan delivered the work for us on time, but also with great quality. He is very communicative and dedicated to his work. Will definetly work with him again in the future. He is my go-to person.
About Kristijan
Senior JS/ReactJS/React Native, NodeJS, Google Apps Script Developer
Skopje, North Macedonia - 1:51 am local time
🤖 AI Automation & Software Architect
✅ 100% Job Success Score
✅ 100+ Jobs Completed
✅ 4,000+ Hours Worked
✅ 10+ Years of Professional Experience
👋 I help startups, growing businesses, and enterprise teams build reliable web, mobile, cloud, and AI-powered products.
I am a Senior Full-Stack Engineer, Tech Lead, and AI/Software Architect with more than 10 years of experience delivering production-ready solutions for clients and global brands, including Reddit, Microsoft, Genentech, Dometic, and Next11.
My work covers the complete product lifecycle, from requirements analysis, system architecture, and UX planning to development, integrations, deployment, optimization, and long-term technical support.
🚀 WHAT I CAN BUILD FOR YOU
✔ AI-powered applications and workflow automation
✔ LLM integrations and agentic workflows
✔ Retrieval-Augmented Generation systems
✔ Structured data extraction and document processing
✔ Speech-to-text and transcription workflows
✔ Human-in-the-loop review and approval systems
✔ SaaS and multi-tenant platforms
✔ Web and mobile applications
✔ REST APIs, webhooks, and third-party integrations
✔ Real-time dashboards and analytics platforms
✔ Bluetooth and Wi-Fi connected-device applications
✔ Internal business tools and process automation
✔ Cloud functions, background processing, and microservices
🤖 AI AND AUTOMATION EXPERIENCE
I am the creator and product architect of ServiceBrief AI, an AI-powered workflow platform for field-service businesses.
ServiceBrief AI transforms calls, emails, voicemails, and technician notes into structured jobs, service reports, customer summaries, follow-up actions, and quote opportunities.
My AI and automation experience includes:
✔ Agentic workflow design
✔ LLM and API orchestration
✔ RAG and company knowledge systems
✔ Prompt and system design
✔ Structured information extraction
✔ Speech-to-text processing
✔ Confidence-aware automation
✔ Human approval workflows
✔ SOP, checklist, and price-book retrieval
✔ Webhook-based multi-step workflows
💻 TECHNICAL EXPERTISE
⚛ Frontend and Mobile
React, React Native, JavaScript, HTML5, CSS3, CSS Grid, responsive interfaces, Bootstrap, mobile UX, and Microsoft Office 365 add-ins.
⚙ Backend and APIs
Node.js, Python, JavaScript, REST, SOAP, webhooks, third-party integrations, Google Apps Script, Google Cloud Functions, App Engine, and Salesforce API.
☁ Cloud and Databases
Firebase, Firestore, Google Cloud, AWS, Cloud Storage, PostgreSQL, MySQL, MongoDB, Microsoft SQL Server, SQLite, and multi-tenant SaaS architecture.
🛠 Development and Delivery
Docker, Git, GitHub, Jira, Notion, Agile workflows, technical architecture, code reviews, refactoring, performance optimization, team leadership, and developer coordination.
👥 LEADERSHIP AND ENTERPRISE EXPERIENCE
I have led and coordinated teams of developers and QA specialists while remaining hands-on with architecture, frontend, backend, mobile development, cloud services, and integrations.
Selected experience includes:
✔ Building connected-product mobile applications for Dometic
✔ Improving advertising creation and scheduling workflows for Reddit Ads
✔ Developing Microsoft Office 365 onboarding add-ins
✔ Building an internal training management platform for Genentech
✔ Architecting real-time sports analytics and coaching platforms
✔ Developing B2B, SaaS, eCommerce, collaboration, and workflow-management products
⭐ WHY CLIENTS WORK WITH ME
✔ Clear and proactive communication
✔ Strong product and business understanding
✔ Practical and maintainable architecture
✔ Reliable project organization
✔ Hands-on technical leadership
✔ Focus on performance, scalability, and usability
✔ Ownership from the initial idea to production release
🎓 I hold a B.S. in Information Systems from the Faculty of Computer Science and Engineering at Ss. Cyril and Methodius University in Skopje.
🤝 Whether you need an experienced developer, technical lead, software architect, or AI automation specialist, I can help turn your requirements into a dependable, production-ready solution.
Steps for completing your project
After purchasing the project, send requirements so Kristijan can start the project.
Delivery time starts when Kristijan receives requirements from you.
Kristijan works on your project following the steps below.
Revisions may occur after the delivery date.
Requirement Gathering
We will discuss the API/Routes needed to be developed for your App or Platform.
API Documentation
I will document all the use case & architecture for all the API/ROUTES to be developed.