Find the best custom software development companies in San Jose, California. All agencies are vetted with real client reviews and transparent pricing.

AI-powered custom software development and staff augmentation delivering scalable web, mobile, and AI solutions
Valletta Software Development is a Malta-headquartered custom software development company that has been building digital products for startups and enterprises since 2009. Operating at the intersection of human engineering expertise and artificial intelligence, the firm specializes in end-to-end software delivery across web, mobile, AI/ML, DevOps, and quality assurance disciplines. With a team of over 200 engineers, designers, and project managers, Valletta Software serves clients primarily across Europe and North America, bringing a mature delivery methodology refined over more than 1,000 successfully completed projects spanning 11 industries. The company operates through two core engagement models. Its staff augmentation practice allows clients to rapidly scale their engineering capacity with mid-level and senior specialists who can begin contributing within days of engagement. Its end-to-end development practice handles full product builds from backend and frontend engineering through AI/ML implementation, offering startup-grade speed with enterprise-level quality. Valletta Software has built particular depth in fintech, e-commerce, healthcare, blockchain, and real estate, delivering solutions that range from social trading platforms and subscription-sharing marketplaces to remote vessel inspection systems and loan processing applications. What distinguishes Valletta Software in a crowded outsourcing market is its commitment to transparency and process rigor. The firm maintains a 15% bench level to ensure flexible scaling, employs only mid-level and senior engineers, enforces mandatory weekly code reviews, and provides granular task-level reporting. This approach has earned the company a 4.9-star rating on Clutch across nearly 50 verified reviews, a Clutch Global Award, and a 98% client recommendation rate.
“They found excellent solutions to every problem, so the project kept moving forward.”
— CIO, Beauty Products Company

Full-cycle software development delivering custom digital solutions with 18+ years of global IT expertise
Innowise is an international full-cycle software development company founded in 2007. Over the past 19+ years, the firm has grown into a multinational operation with 3,500+ professionals spanning offices across Europe, North America, and Asia. The company specializes in helping businesses build and scale digital products, modernize legacy systems, and adopt advanced technologies such as AI, blockchain, IoT, and AR/VR. With more than 1,600 custom software solutions delivered to clients in over 40 industries, Innowise has established itself as a dependable partner for organizations ranging from startups to large enterprises. The company operates on a full-cycle development model, covering every stage from initial consulting and business analysis through UX/UI design, engineering, quality assurance, deployment, and ongoing support. Its technical teams work across a broad technology stack including JavaScript frameworks, native and cross-platform mobile development, cloud platforms like AWS, Azure, and GCP, and enterprise systems such as SAP, Salesforce, and Microsoft Dynamics 365. Innowise also maintains dedicated practices in machine learning, big data analytics, robotic process automation, and metaverse development. Innowise has earned notable industry recognition, including placement on the Inc. 5000 list of fastest-growing U.S. companies and consecutive appearances on the IAOP Global Outsourcing 100 from 2022 through 2025. The company holds ISO 13485 certification for medical device software development. With a reported 93% client return rate, the firm emphasizes long-term partnership and consistent delivery quality. Innowise offers flexible engagement models including dedicated development teams, IT staff augmentation, and project-based outsourcing, enabling clients to scale technical capacity on demand.
“I was impressed by how good the code quality was right from the beginning. Their frequency and style of communication were to the point and never more than needed.”
— CEO, Zero Beta

Oracle Eloqua and Adobe Marketo consulting for B2B marketing teams, focused on strategy, integration, and privacy compliance.
4Thought Marketing is a specialized, remote-first marketing automation agency providing enterprise-grade automation, operations, and privacy compliance solutions to clients in North America, Latin America, Europe, and Asia. For over 15 years, we’ve helped organizations around the world optimize their marketing technology stack with deep expertise in Eloqua and Marketo platform implementation, migration, and ongoing optimization. Our certified marketing automation experts deliver comprehensive services including advanced campaign management, complex lead scoring and nurturing setups, CRM integrations, and multi-channel automation strategies across both Eloqua and Marketo platforms. We specialize in large-scale enterprise implementations, offering everything from platform migrations and custom dashboard development to ongoing account health audits and performance enhancement. As your dedicated marketing automation consulting partner, we provide tailored integration services, data segmentation, list management, and team training for both Eloqua and Marketo to ensure maximum platform adoption and ROI. Our proven track record includes managing complex enterprise implementations while maintaining the highest standards of regulatory compliance and data-driven customer engagement.
Digital Development and Design Agency with strong AI capabilities
Vincit is a trusted partner for companies like Logitech, Cisco, The New York Times and LTK in developing their digital products and services. With roots in Finland and presence in the US since 2016 we are now over 500 experts ready to serve you. We combine meaningful user experience design to top-tier technical development for mobile, web and cloud. With the use of latest AI tools, we are able to deliver projects more efficiently and help your organization gain AI-Driven-Development capabilities throughout the collaboration. Ask us for free consultation and quote for your project. We are especially interested in challenging projects with established companies.
Production-Grade AI & Workflow Systems for Serious Teams
Spiral Scout helps companies turn messy, high-stakes workflows into durable, agent-driven production systems. We step in where internal teams or generic agencies stall — typically at the intersection of automation, data, and AI that must operate inside real business constraints. We don’t sell headcount or ticket delivery. We design and ship working systems that run reliably, scale over time, and stand up to audits. From AI agents and long-running workflow orchestration to CPQ and complex SaaS platforms, we take responsibility from architecture through production readiness — and leave clients with systems they can own and operate independently.

Diffco is a San Jose-based company specializing in AI, custom software development, and staffing services. With more than 17 years of expertise in creating dependable solutions for mobile, web, and AI applications, it is committed to driving and supporting the growth of your business. Products we developed are used by renowned companies such as American Express, Starbucks, Whole Foods, Mars, and many successful startups like Maze, Happier, and Legion Farm, among many others. Why Diffco? For your project development: -Client-driven approach and clear communication -Transparent processes and billing -Detailed reporting and deliverables -Dedicated project team with no cross-project sharing For your team augmentation: -Transparent pricing with no hidden fees -Vetting and verification of team member expertise -Fast and straightforward hiring for both long and short-term projects -A dedicated account manager to facilitate interactions with both candidates and hired personnel
Waverley is a software engineering company with over 400 technical specialists building distributed development teams in Bolivia, Mexico, Romania, Vietnam, and Ukraine to augment your internal team’s capabilities.
Niantic inspires people to explore the world, together. Our mission is to use emerging augmented reality (AR) technology to enrich our experiences as human beings in the physical world. Originally formed at Google in 2011, we are now an independent company with a strong group of investors including Nintendo, The Pokémon Company, and Alsop Louie Partners.
Every year, Genesys® orchestrates more than 70 billion remarkable customer experiences for organizations in more than 100 countries. Through the power of our cloud, digital and AI technologies.

WLCM is a custom software design and development studio. A tight-knit and long-standing veteran team, we've built our reputation winning "best in class" recognition by Apple, “Best of Experience Design” by FastCo, and "Best in Business" by Inc.
Altoros is a leading technology consulting firm that specializes in custom software development, cloud automation, and artificial intelligence solutions. With a focus on innovation and quality, Altoros helps businesses accelerate digital transformation and optimize operations through tailored digital strategies. Leveraging expertise in various industries, the company delivers scalable solutions that drive efficiency and growth.

G360 Technologies helps companies develop custom software solutions while maximizing the opportunities created by the use of Cloud & AI. We take the time to understand our customers unique business challenges and are 100%-focused on business outcomes.

AI, XR, and healthcare software experts building secure, scalable digital products and Software as a Medical Device (SaMD) solutions.
CitrusBits is a digital innovation company specializing in custom software development, AI solutions, immersive XR technologies, and Software as a Medical Device (SaMD) platforms. With over 15 years of experience, we help startups, healthcare organizations, and enterprises transform complex ideas into scalable, secure, and high-impact digital products. Our multidisciplinary team designs and develops mobile apps, SaaS platforms, AI-driven systems, and immersive training solutions that improve real-world outcomes. From product strategy and UX design to engineering and deployment, we partner closely with clients to deliver reliable, future-ready technology. At CitrusBits, our focus is on innovation, quality, and building meaningful digital solutions that solve real problems across healthcare, enterprise, and emerging technology industries.