Top C# (C-Sharp) Development Firms in California

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Software Development C# (C-Sharp) Development United States California

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Top Featured C# (C-Sharp) Development Firms

Poterby Tech
(0 review)
Making brands matter
Welcome to Poterby Technologies, where innovation meets execution. We are a leading software development agency committed to transforming ideas into scalable and impactful digital solutions. With a passion for technology and a focus on excellence, we empower startups, businesses, and organizations to thrive in the digital age.
Looking for work in C# (C-Sharp) Development
Located in Lagos, Nigeria
From €1,000 for C# (C-Sharp) Development
Worked in Retail (+1)
Speaks English
1-10 members
Instinctools
5
(10 reviews)
Your AI-powered Engineering Partner
Top awarded
Meet *instinctools - a global AI-powered software engineering company with over 25 years of experience. We help both SMBs and Enterprises build robust, scalable software solutions that excel in functionality and design. Our core services include: Agentic AI enablement Custom software development enhanced by deep AI expertise Digital product engineering Business process automation Legacy system modernization Advanced data analytics and visualization Cloud infrastructure and DevSecOps Headquartered in the USA (Maryland) and Europe (Germany), *instinctools offers convenient locations for meeting and collaborating directly with our clients. We have development centers in Poland, LATAM, India, and Kazakhstan that combine global expertise with a strong price-quality balance to ensure exceptional results across time zones. Our work is backed by ISO-certified quality standards, strategic partnerships with leading tech platform, and a long-standing commitment to engineering excellence. Instinctools holds a broad portfolio of regional and industry-specific certifications, including CIR, HIPAA, and other compliance frameworks required for regulated markets. The 2025 Annual Customer Satisfaction Index is 9.1 out of 10.
Looking for work in C# (C-Sharp) Development
Located in Potomac, United States (+4)
From €10,000 for C# (C-Sharp) Development
Worked in Construction (+10)
Speaks English, German(+1)
201-500 members
U1CORE
5
(12 reviews)
U1CORE — A product studio for multi-sided platforms. Marketplaces, exchanges, auctions, fundraising
Highly recommended
Top awarded
YOUR PARTNER TO BUILD MULTI-SIDED PLATFORMS $720M moved through one platform we built. Millions of live listings on another. 300+ products shipped. 🔔 Book a free call: https://calendly.com/hello-u1core/30min 🌐 https://www.u1core.com/ What you get We do: the full platform. Multi-role flows, payments, trust & safety, admin tooling, infrastructure that holds at peak load. You get: a product decision-makers trust on first impression, and users who move through it without friction. So you can: grow revenue, close your round, automate operations, and charge a premium. Services Product Design: UI/UX, design systems, prototyping, platform-native patterns for marketplaces, auctions, exchanges, donation flows. Product Engineering: React, Next.js, Vue; Node.js, Python, .NET; mobile, payments, multi-role architecture, admin tooling, DevOps. Discovery & Strategy: cold-start strategy, trust & safety, take-rate modeling, MVP scoping, UX audits. Custom Development: marketing sites and landing pages for platform companies. Why founders pick us One lane. Marketplaces, exchanges, auctions, donation platforms. We already know how products in your category delivered. We lead. We arrive with a point of view, flag what won't work, and explain why. One team, kickoff to launch. The product you ship is the product we built. Twice the pace. Six weeks where others quote three months. $720M+ processed. CSS Design Awards (2× Site of the Day, 4× Best UX, 4× Best UI, 4× Best Innovation, 4× Special Kudos), Orpetron, TOP 10 on Dribbble. 300+ clients, and the ones who matter come back. If your product only works when two sides of a market trust it at the same moment, that's our entire job. Let's talk.
Looking for work in C# (C-Sharp) Development
Located in London, United Kingdom
From €5,000 for C# (C-Sharp) Development
Worked in E-commerce (+15)
Speaks English
11-50 members

All C# (C-Sharp) Development Companies in California

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