Best C# Developers in the United States

9 Companies - Rankings updated: September 03, 2026

Every agency featured on DesignRush is vetted for expertise and client satisfaction to support your decision-making. Some listings may be sponsored.

United States × C# Development × Corporate Services × $25,000 - $50,000 × Clear Filters
  • Diffco

    Verified Verified by the DesignRush team for authenticity and credibility.

    Your trusted AI software development partner

    Diffco is a software development company that builds cross-platform mobile apps, bespoke SaaS portals, custom database architectures, and admin management panels. The studio deploys clean Python, Node.js, React, and Swift codebases alongside automated testing setups and CI/CD pipelines engineered for...

    Top Services:

    • AI Development
    • Software Development
    • Staff Augmentation
    • Mobile App Development
    • Web Development
    • Show more
    Location
    San Jose, California
    Number of Employees
    50 - 99
    Average Hourly Rate
    $110/hr
    Minimal Budget
    $25,000 - $50,000
    Portfolios Count
    31 Projects Listed

    Diffco Services

    • AI Development
    • Software Development
    • Staff Augmentation
    • Mobile App Development
    • Web Development
    • eCommerce Development
    • IoT
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Mars
    • Food Rocket
    • FlashGrid
    • Nokia
    • Instreamatic
    • Quire
    • Legionfarm
    • Latoken
    • Genius One
    • Shift
    Data sourced from the agency's DesignRush profile

    Diffco Reviews & Testimonials

    • Oleg Sotnikov
      Oleg Sotnikov CEO at AppMaster
      5.0

      AI Development Review from Oleg Sotnikov

      Diffco built a complex, production-grade AI agentic system and backend for our client's fintech platform owning architecture, AI/ML components, and AI agents in a security- and compliance-sensitive environment. They delivered on time and within budget, communicated proactively, and operated like part of our own team, taking ownership and suggesting better solutions throughout. Deep AI/ML and senior backend expertise. We'd happily work with them again.

    • Julia Platova
      Julia Platova VP Strategic Partnerships at OVA Solutions
      5.0

      Mobile App Development Review from Julia Platova

      We partnered with Diffco for a comprehensive software development project aimed at delivering a mobile application and backend system for our client. The goal was to create a seamless, secure, and scalable solution within a 4-month timeline and $50k-$200k budget. Diffcos team was highly professional from start to finish. They handled everything: UI/UX design, backend architecture, API integration, and deployment. After the launch, they continued to support us with maintenance and performance optimization. The application received positive feedback and has proven stable and scalable. Were highly satisfied with Diffcos expertise, commitment, and ability to deliver real results.

    • Max Shmatkov
      Max Shmatkov Manager at Centerligh
      5.0

      Mobile App Development Review from Max Shmatkov

      As an advantage of working with this company I’d like to note that their Agile development method is amazing! Diffco earned my trust through such approach and the team’s professional attitude.

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews
  • FUELING DISRUPTION

    EffectiveSoft is an AI-enabled product engineering company focused on digital products and enterprise systems. We combine software engineering, UX expertise, and AI capabilities to help companies build products that can adapt to changing requirements, integrations, and growth...

    Top Services:

    • Software Development
    • Mobile App Development
    • Big Data Analytics
    • AI Development
    • ERP Consulting
    • Show more
    Location
    San Diego, California
    Number of Employees
    250 - 499
    Average Hourly Rate
    $50/hr
    Minimal Budget
    $25,000 - $50,000
    Portfolios Count
    29 Projects Listed

    EffectiveSoft Services

    • Software Development
    • Mobile App Development
    • Big Data Analytics
    • AI Development
    • ERP Consulting
    • IoT
    • Cloud Consulting
    • DevOps Consulting
    • UI/UX Design
    • Staff Augmentation
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • CITY INDEX
    • TruBridge
    • CNote
    • Plato
    • Intelon Optics
    • InCheq
    • Nissin Foods
    • Soutron Ltd.
    • BullionRock
    • InContinuum
    Data sourced from the agency's DesignRush profile

    EffectiveSoft Reviews & Testimonials

    • Alex Silverstein
      Alex Silverstein Chief Technology Officer at Unified Digital Group, LLC
      5.0

      Software Development Review from Alex Silverstein

      Over the past 13 years, I’ve valued the opportunity to work alongside this team. Their expertise played a central role in my company’s success, and I’ve come to rely on them for their consistency, attention to detail, and thoughtful approach.

    • Philipe Araujo
      Philipe Araujo Business Analyst and Quality Engineer at Motive Retail
      4.8

      Software Development Review from Philipe Araujo

      We have had a highly positive experience utilizing EffectiveSoft's staff augmentation services for our Business Analyst and Quality Engineer needs. The professionals provided were not only highly skilled and knowledgeable but also integrated seamlessly with our existing team, requiring minimal ramp-up time. Their expertise in their respective fields significantly enhanced our project's efficiency and overall quality. We confidently recommend EffectiveSoft for any organization seeking top-tier talent to augment their teams and drive successful project outcomes.

    • Sasja Ihn Christensen
      Sasja Ihn Christensen Senior Director, Head of Digital Business Development at MAERSK BROKER
      5.0

      Software Development Review from Sasja Ihn Christensen

      Maersk Broker is pleased to provide this reference letter for EffectiveSoft, our trusted collaborator for complex web projects. From the initial stages of our projects, the team at EffectiveSoft demonstrated a deep understanding of our requirements and have been apro-active part of any problem-solving process. The team of offshore developers has been well-run through their lead developer, and we have only experienced a professional approach to our projects, as well as a pleasant and trust-based collaboration = between all members in the EffectiveSoft team and our own team. EffectiveSoft has furthermore proved to be highly flexible, adapting to our evolving needs and delivering reliable results under shifting circumstances and shifting priorities. They have furthermore been very quick to find and add the necessary resources to the team when needed, and we have only experienced professional and highly skilled consultants. This has also made on-boarding into projects faster and more efficient. In conclusion, it has been a pleasure working with EffectiveSoft, and I have no doubt that they will continue to be an asset to any collaborators in the future, adding value through their professionalism, dedication and understanding of business needs.

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews
  • Dedicated Teams That Build Complex Software Systems

    SiliconMint designs, develops, and supports mission-critical software systems. Based in San Francisco, SiliconMint has offices in New York and Europe to serve clients across the globe...

    Top Services:

    • Software Development
    • Mobile App Development
    • IoT
    • AI Development
    • Cybersecurity
    • Show more
    Location
    San Francisco, California
    Number of Employees
    50 - 99
    Average Hourly Rate
    $55/hr
    Minimal Budget
    $25,000 - $50,000
    Portfolios Count
    7 Projects Listed

    SiliconMint Services

    • Software Development
    • Mobile App Development
    • IoT
    • AI Development
    • Cybersecurity
    • Blockchain
    • VR/AR
    • Big Data Analytics
    • IT Services
    • Cloud Consulting
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Verizon
    • Yahoo Japan
    • NASDAQ
    • NYSE
    • Goldman Sachs
    • Barclays
    • BCG
    • Wargaming,net
    • AA
    • orange
    Data sourced from the agency's DesignRush profile

    SiliconMint Reviews & Testimonials

    • Leon Hounshell
      Leon Hounshell CTO, Verizon
      5.0

      Software Development Review from Leon Hounshell

      Using SiliconMint’s AI engine and their engineering team was a great decision for us. They built the core foundation of our ThingSpace IoT platform on time and within budget, helping us serve millions of customers across the country. I would highly recommend the SiliconMint team for their drive and dedication to the art of software architecture and development.

    • Leonid Zhukov
      Leonid Zhukov Partner and Associate Director at Boston Consulting Group (BCG)
      5.0

      Software Development Review from Leonid Zhukov

      I’m always impressed by the technical depth & breadth of SiliconMint’s engineering team and the passion they bring to our projects. We’ve worked with them on distributed systems, data science projects, and a predictive maintenance system for the oil and gas sector. Every time, they blew me away with their experience, passion, energy, and the overall dedication for how they approach software engineering and delivery.

    • Steve Grice
      Steve Grice Head of Technology Global Transaction Services at Royal Bank of Scotland
      5.0

      Cybersecurity Review from Steve Grice

      SiliconMint built a real-time fraud detection system for us in a record period of time, with precision and recall that rivals the best in the industry. I was pleasantly impressed by their passion, dedication, and attention to detail in how they approached software development, driving excellence and speed within our organisation.

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews
  • Product Engineering, AI, Data & Cloud Consulting

    We are a digital product, chatbot solution, and software development company and your guide on the digital transformation journey. Right from materializing your ideas through rapid application development, to improving processes via RPA and AI, to streamlining your customer support via chatbots, we do it all...

    Top Services:

    • Software Development
    • Mobile App Development
    • AI Development
    • Software Testing
    • Big Data Analytics
    • Show more
    Location
    Austin, Texas
    Number of Employees
    100 - 249
    Average Hourly Rate
    $40/hr
    Minimal Budget
    $25,000 - $50,000
    Portfolios Count
    9 Projects Listed

    Maruti Techlabs Services

    • Software Development
    • Mobile App Development
    • AI Development
    • Software Testing
    • Big Data Analytics
    • Cloud Consulting
    • IT Services
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Zydus Hospitals
    • Symphony Aircoolers
    • Kalpataru Group
    • Smart AI
    • Sterling Accuris Diagnostics
    • Piramal
    • Optimizely
    • Telefonica
    • Ubisoft
    • Granite
    Data sourced from the agency's DesignRush profile

    Maruti Techlabs Reviews & Testimonials

    • Undisclosed
      Undisclosed CEO at Online Telehealth Company
      5.0

      Software Development Review from Undisclosed

      Maruti Techlabs has delivered quality work on time and excelled at planning. They’ve built an application and CRM from scratch using React and the client’s design work. The team stands out for their professionalism and seamless execution. They manage the project well, using weekly calls to track progress and communicating over phone calls and Slack. Overall, it’s easy to work with them.

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews
  • We find, build and manage remote teams.

    Away Digital Teams specializes in recruiting and managing top talent in Vietnam for businesses seeking to establish and oversee remote teams. Our comprehensive service ensures seamless team building and management, enabling companies to thrive in today's digital landscape...

    Top Services:

    • Digital Services
    • Web Development
    • Software Testing
    • Mobile App Development
    • Software Development
    • Show more
    Location
    Austin, Texas
    Number of Employees
    250 - 499
    Average Hourly Rate
    $25/hr
    Minimal Budget
    $25,000 - $50,000
    Portfolios Count
    4 Projects Listed

    Away Digital Teams Services

    • Digital Services
    • Web Development
    • Software Testing
    • Mobile App Development
    • Software Development
    • IT Services
    • DevOps Consulting
    • Accounting
    • Customer Support
    • SEO
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Champion Data
    • Propel Ventures
    • Rendr
    • My Occ Health Record
    • Lexer
    • Accent Group
    Data sourced from the agency's DesignRush profile
  • #1 in Cybersecurity, Blockchain, AI&ML, Python, NodeJS

    Apriorit is a leader in smart contract development, cybersecurity services, along with advanced data management technologies. Other services offered by this IT firm include SaaS engineering, Driver development, system programming, professional reverse engineering, blockchain, AI&ML and more...

    Top Services:

    • Software Development
    • Blockchain
    • IT Services
    • Cybersecurity
    • Web Development
    • Show more
    Location
    Lynn, Massachusetts
    Number of Employees
    250 - 499
    Average Hourly Rate
    $100/hr
    Minimal Budget
    $25,000 - $50,000
    Portfolios Count
    8 Projects Listed

    Apriorit Services

    • Software Development
    • Blockchain
    • IT Services
    • Cybersecurity
    • Web Development
    • Web Design
    • AI Development
    • Mobile App Development
    • Software Testing
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Agemni
    • PayDay Resources
    • Borta
    • ETRI
    • VisionWorks
    Data sourced from the agency's DesignRush profile
  • Your Vision, Our Experts with Portal & Mobile Framework, Powerful Results!

    Why build from scratch! Our Portal, Mobile and AI framework provides 30-40% increased time to market. Built with Enterprise Security/Compliance for Azure/AWS clouds. ContentActive (Houston) provides Strategy, UI/UX, Web/Mobile/AI/Automation/IoT & DevOps. Your Vision, Our Experts, Powerful Results!...

    Top Services:

    • Software Development
    • Mobile App Development
    • AI Development
    • DevOps Consulting
    • Web Development
    • Show more
    Location
    Houston, Texas
    Number of Employees
    Under 49
    Minimal Budget
    $25,000 - $50,000
    Portfolios Count
    4 Projects Listed

    ContentActive, LLC Services

    • Software Development
    • Mobile App Development
    • AI Development
    • DevOps Consulting
    • Web Development
    • IoT
    • Big Data Analytics
    • ERP Consulting
    • UI/UX Design
    • Digital Strategy
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • AEI Energy
    • Abitibi-Consolidated
    • American Medical Writers Association
    Data sourced from the agency's DesignRush profile
  • Redefining Web and Mobile Experiences

    Based in Austin, The BHW Group is a renowned web and mobile design & development firm. With a legacy of 13 years, we have crafted award-winning applications, earning recognition as a 2015 SXSW Interactive finalist and a 2014 National Association of Government Communicators first place winner. Our impressive...

    Top Services:

    • Mobile App Development
    • Web Design
    • Web Development
    • UI/UX Design
    • Show more
    Location
    Austin, Texas
    Number of Employees
    Under 49
    Average Hourly Rate
    $115/hr
    Minimal Budget
    $25,000 - $50,000
    Portfolios Count
    5 Projects Listed

    The BHW Group Services

    • Mobile App Development
    • Web Design
    • Web Development
    • UI/UX Design
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Chick-fil-A
    • The University of Texas
    • Deloitte
    • Buxton
    • The Habit Burger Grill
    • Gemalto
    • UT Southwestern Medical School
    • Texas Department of Transportation
    • Rush Enterprises
    • The American Association of Nurse Practitioners
    Data sourced from the agency's DesignRush profile

    The BHW Group Reviews & Testimonials

    • Erich Dahlke
      Erich Dahlke Review from Google
      5.0

      Erich Dahlke's Review Sourced from Google

      BHW is hands down the best contract development team I have worked with. They are honest, extremely responsive, detail oriented, talented, and always on schedule with deliveries. We engaged them on a fixed fee development project and upon completion, transitioned to monthly resources to augment our internal development team, so we could maintain the newfound development velocity. Highly recommend them for mobile app & web development as well as design services.

    • Matt Mackowski
      Matt Mackowski Review from Google
      5.0

      Matt Mackowski's Review Sourced from Google

      Over the past four years I've worked with BHW on several projects and I am happy to give them my highest possible recommendation. They've done more than just build apps for our organization, they've provided robust and creative solutions to help meet our business needs, and it is no exaggeration to say that these solutions have played a crucial role in our rapid growth. The BHW team is friendly, responsive, and professional; and not only do they really know the technology, but more importantly, from our point of view, they know how to best apply the right technology to our particular environment. As mentioned, they have my highest recommendation and I'm sure we plan to continue working with them for years to come.

    • Jeff Sikes
      Jeff Sikes Review from Google
      5.0

      Jeff Sikes's Review Sourced from Google

      Highly recommended, quality work. Our organization has partnered with The BHW Group for over seven years. They create highly successful applications, specific to our needs. Speaking as a developer myself, the code produced by their team is clean and simple to read, making it easy to update the project as needed by our own internal development group.

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews
  • A Custom Software Development Company

    Inument is a custom software development company that specializes in providing tailored offshore IT staff augmentation, custom development, and seamless digital integration services...

    Top Services:

    • Web Design
    • Web Development
    • eCommerce Development
    • WordPress Website Design
    • Software Testing
    • Show more
    Location
    New York City, New York
    Number of Employees
    50 - 99
    Average Hourly Rate
    $150/hr
    Minimal Budget
    $25,000 - $50,000

    Inument Services

    • Web Design
    • Web Development
    • eCommerce Development
    • WordPress Website Design
    • Software Testing
    • AI Development
    • Mobile App Development
    • Software Development
    • Staff Augmentation
    • IT Services
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • AI Industry
    • Software & IT Services Industry
    • Corporate Services Industry
    Data sourced from the agency's DesignRush profile

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