Transforming Visions into Reality with Cutting-Edge Tech

Specializing in C#, React, and Node.js, I craft custom solutions and pioneer innovative products to set your business apart in the digital world. With 10+ years of experience and Top 3% Toptal verification, you get senior-level expertise from day one.

TOP 3% TALENT

Vetted by Hire Me on Toptal
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50+

Companies Served Worldwide

100+

Successful Projects Delivered

10+

Years of Proven Excellence

Top 3%

Toptal Verified Developer

Gavrilo Mumovic

Founder & Lead Software Engineer

10+
Years Experience
5+
Countries Served
Top 3%
Toptal Talent
100%
Client Satisfaction

About Rashtan Soft

Founded by Gavrilo Mumovic, a senior software engineer with over 10 years of experience, Rashtan Soft delivers enterprise-grade software solutions with a boutique approach. As a verified Top 3% Toptal developer, I bring the expertise of a large agency with the personal attention and flexibility of working directly with the founder.

My journey in software engineering spans from building complex industrial systems at Calsep A/S to architecting game infrastructure at Illuvium, with successful projects for companies like StubHub and healthcare platforms.

Whether you need a robust back-end system, a modern web application, or cloud infrastructure that scales, you get direct access to senior-level expertise without the overhead of a large agency.

Empowering Innovation with Core Capabilities

At the heart of my work lies a commitment to not just meet, but exceed the technological frontier. Here's how I stand out.

Mastering Complexity with C#

Harness the power of C# for enterprise-grade software solutions with 14 years of proven expertise. From AWS Lambda serverless architectures to complex desktop applications, I build sophisticated systems that handle deep business logic and high-performance requirements.

Dynamic Interfaces with React

Elevate the user experience with React and TypeScript to create responsive, interactive interfaces that users love. With 6 years of React expertise, I build progressive web applications and modern SPAs that combine beautiful design with optimal performance.

Efficiency at Scale with Node.js

Leverage Node.js for lightweight, scalable network applications and microservices. I build REST APIs, real-time systems with WebSockets, and serverless functions that handle high throughput and concurrent connections efficiently.

Flexibility and Speed with Agile

Adopting an Agile approach with clear communication and iterative delivery, your project stays flexible to changing requirements while maintaining momentum. Projects are delivered in sprints, allowing you to see progress weekly.

Tailor-Made Solutions

From initial consultation to production deployment and beyond, I provide end-to-end custom development services. You receive a complete solution including documentation, CI/CD pipelines, and post-launch support.

Driving Future Trends

Beyond client work, I develop and maintain production software products serving users across multiple countries. The experience from managing complete product lifecycles translates directly into better client solutions.

What We Deliver

End-to-end development services tailored to your business needs

Full-Stack Development

Complete web and mobile application development from database design to polished user interfaces. I build production-ready systems using modern frameworks and best practices.

  • React/Next.js frontends with TypeScript
  • .NET Core / Node.js back-end APIs
  • SQL Server, PostgreSQL, DynamoDB databases
  • CI/CD pipelines & automated testing

Cloud Architecture

Design and implement scalable cloud infrastructure on AWS and Azure. From serverless functions to containerized microservices, I build architectures that grow with your business.

  • AWS Lambda, ECS, S3, CloudFront
  • Azure App Service, Functions, Static Web Apps
  • Docker & Kubernetes orchestration
  • Terraform infrastructure as code

Performance Optimization

Identify and eliminate bottlenecks in your existing systems. I've achieved results like reducing 5-hour processes to 20 seconds and cutting query times by 60%.

  • Database query optimization & indexing
  • Caching strategies & CDN configuration
  • Memory & CPU profiling
  • Load testing & scalability planning

Legacy Modernization

Breathe new life into aging systems. I migrate legacy codebases to modern frameworks while preserving business logic and minimizing disruption to operations.

  • .NET Framework → .NET 8/9 migration
  • Monolith to microservices decomposition
  • On-premises to cloud migration
  • API-first architecture redesign

Flexible Engagement Models

Choose the model that fits your project and budget

Hourly

Pay as you go

Ideal for ongoing support, code reviews, consulting, or small tasks where scope is flexible.

  • No minimum commitment
  • Weekly time tracking
  • Scale up or down anytime
MOST POPULAR

Project-Based

Fixed scope & price

Best for well-defined projects with clear requirements, milestones, and deliverables.

  • Defined scope & timeline
  • Milestone-based payments
  • Predictable budget
  • Post-launch support included

Retainer

Dedicated monthly hours

Perfect for long-term partnerships requiring consistent development capacity and priority access.

  • Reserved monthly capacity
  • Priority response times
  • Discounted rates

How I Work With You

A proven 5-step process to bring your project from idea to production

1

Discovery

Understand your goals, requirements, and technical constraints through detailed consultation.

2

Design

Architect the solution, create technical specs, and define milestones and deliverables.

3

Development

Build iteratively in sprints with weekly demos, code reviews, and progress updates.

4

Deployment

Launch with CI/CD pipelines, monitoring, and zero-downtime deployment strategies.

5

Support

Ongoing maintenance, performance monitoring, bug fixes, and feature enhancements.

Featured Projects

Real-world solutions delivering measurable results

Dental Lab Guru

Comprehensive dental laboratory management system serving laboratories across 5+ countries.

  • • Used by labs in 5+ countries
  • • Real-time SMS & email notifications
  • • Stripe & PayPal payments
  • • Multi-language support
React.NET CoreAzureDocker

Illuvium Infrastructure

Architected complete back-end infrastructure for flagship game titles, handling thousands of concurrent users.

  • • Built from ground up on AWS Lambda
  • • Upgraded to .NET 9 for performance
  • • Reduced cold start times significantly
  • • Designed MMO game services
C#AWS Lambda.NET 9Terraform

MedProctor Optimization

Performance optimization for healthcare platform, dramatically reducing processing times.

  • • 5 hours → 20 seconds (99.9% faster)
  • • Fixed SQL Server bottleneck
  • • 60% faster EF queries
  • • Bulk insert strategies
C#SQL ServerAWS LambdaEF Core

StubHub Payments

Developed payment processing features for StubHub's ticketing platform, increasing conversion rates.

  • • Increased large order processing by 2%
  • • Led team of 2 engineers
  • • Improved revenue and conversion
  • • Mentored junior developers
C#ReactJavaScriptSQL Server

PVTsim Nova

Revolutionary oil and gas simulation platform with industry-first ML-based automated data import.

  • • First ML-based PVT data import worldwide
  • • Created new revenue stream
  • • Built Web API with C# & Python SDKs
  • • Docker/Kubernetes deployment
C#.NET CorePythonMLDocker

VLXE Multi-Language SDK

Created comprehensive SDK and samples in C#, Python, and JavaScript for VLXE API.

  • • SDK in 3 languages (C#, Python, JS)
  • • Complete UI from Figma design
  • • Comprehensive code samples
  • • Blazor & Razor implementation
C#PythonJavaScriptBlazor

Don't take my word for it

Read what my clients have to say about the transformative impact my services have had on their businesses.

Igor Sakotic
— We tasked them with a complex project, and they delivered beyond expectations. Their team's expertise in React and Node.js transformed our operations, making them more efficient and scalable.
Igor Sakotic - Sakotic Lab
Dr. Torben Laursen
— From our first consultation, it was clear that they were fully committed to understanding our unique needs. The custom C# solution they developed has become the backbone of our business operations.
Dr. Torben Laursen - VLXE AS
Mika Andjelic
— Their Agile approach made all the difference in our project's success. We were kept in the loop at every stage, with flexibility that allowed for real-time adjustments. The result? A product that perfectly matched our vision.
Mika Andjelic - Andjelic Vinery

Frequently Asked Questions

Everything you need to know about working with Rashtan Soft

I follow an Agile methodology with clear milestones and regular communication. Projects typically start with a discovery phase, followed by iterative development sprints with weekly check-ins.

Rates vary based on project complexity. I offer both hourly and project-based pricing. For Toptal clients, rates are set through their platform. For direct engagements, I provide custom quotes after understanding your needs.

Yes, I provide post-launch support and maintenance for all projects including bug fixes, performance monitoring, security updates, and feature enhancements.

A simple web application might take 4-8 weeks, while a complex enterprise system could take 3-6 months. During our initial consultation, I'll provide a detailed timeline estimate.

Absolutely. I understand the importance of confidentiality and am happy to sign NDAs before discussing project details.

Yes, I regularly collaborate with existing development teams. I'm experienced with GitHub, Azure DevOps, Jira, Slack and can adapt to your team's workflows.

Let's Build Something Great Together

Ready to start your project? Get in touch today.

Get In Touch

Location

Trebinje, Bosnia and Herzegovina

Available for remote work worldwide

Response Time

Within 24 hours

Why Work With Rashtan Soft?

  • Direct access to senior-level expertise (10+ years)
  • Top 3% Toptal verified developer
  • Proven track record across 5+ countries
  • Flexible engagement (part-time or project-based)
  • Personal attention from founder on every project

Schedule a Free Consultation

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