Solutions
Web application development services
Deliver secure, scalable web applications that improve user experiences, modernise legacy systems and accelerate digital transformation.
Custom web application development
Modern organisations need more than off-the-shelf software. They need bespoke digital solutions that support unique business processes, integrate seamlessly with existing technology and evolve as organisational needs change.
Our custom web application development services combine user-centred design, software engineering and cloud-native architecture to create secure, scalable applications that improve operational efficiency, enhance customer and employee experiences, and support long-term digital transformation. Whether you’re developing a customer portal, internal business application, SaaS platform or modernising a legacy system, we build solutions that are accessible, resilient and engineered for continuous improvement.
Our web application development services include
Whether you’re launching a new digital product or modernising an existing platform, we provide end-to-end web application development services that deliver measurable business value.
Custom web application development
We build bespoke web applications that streamline operations, automate business processes and improve customer and employee experiences. Every solution is designed around your users, objectives and technology landscape.
Enterprise application modernisation
Transform legacy applications into secure, scalable digital platforms through cloud migration, application re-platforming, refactoring and API-led modernisation that reduces technical debt and improves long-term maintainability.
Customer & employee portals
We develop secure self-service portals, intranets and business applications that improve engagement, simplify service delivery and provide users with seamless access to information, workflows and digital services.
Systems integration & API development
Our integration specialists connect web applications with CRM, ERP, payment, identity and third-party platforms through secure REST APIs and GraphQL services, enabling data to flow efficiently across your organisation.
UX, accessibility & service design
Combining user research, UX design and accessibility expertise, we create intuitive digital experiences that meet WCAG standards, improve adoption and support users across every device.
Application support & continuous improvement
From performance monitoring and security updates to feature enhancements and managed support, we help your applications remain secure, reliable and aligned with changing business needs.
Did you know?
60%
Only 60% of surveyed digital identity services adhere to WCAG 2.0 AA or higher accessibility standards.
Source: UK Department for Science, Innovation and Technology
How we deliver web application development services
Building successful web applications requires more than development expertise. We combine modern engineering practices with proven delivery methodologies to create applications that are resilient, secure and built to evolve.
Modern technology stack
Our teams develop full-stack applications using proven technologies including React, Angular, Vue.js, Next.js, .NET, Node.js, Java and Laravel, selecting the most appropriate tools to meet your business, security and scalability requirements.
Cloud-native engineering
Using Microsoft Azure, Amazon Web Services (AWS), Docker, Kubernetes and serverless services, we develop cloud-native applications that are resilient, scalable and optimised for performance, availability and cost efficiency.
Secure by design
Security is embedded throughout our software development lifecycle. We implement secure coding practices aligned with OWASP, alongside OAuth 2.0, OpenID Connect, Single Sign-On (SSO), Microsoft Entra ID, multi-factor authentication (MFA) and role-based access control (RBAC) to protect applications, users and data.
Quality engineering & DevSecOps
We integrate automated testing, unit testing, integration testing, user acceptance testing (UAT), continuous integration and continuous deployment (CI/CD) throughout delivery, enabling rapid, reliable software releases without compromising quality or security.
Data & connected platforms
Our applications integrate with enterprise databases including SQL Server, PostgreSQL, MySQL and MongoDB, supporting real-time reporting, analytics, workflow automation and data-driven decision making across connected digital platforms.
Agile delivery
Working collaboratively through discovery, architecture, design, development and optimisation, our multidisciplinary teams use agile delivery practices to ensure transparency, flexibility and continuous improvement throughout every stage of your project.
Why leading organisations choose CACI as their web application development company
Our multidisciplinary teams combine strategic thinking with technical expertise to deliver web applications that create lasting value for organisations operating in complex and highly regulated environments.
User-centred approach
Every decision starts with your users. Through research, service design and iterative development, we create intuitive digital experiences that improve adoption, satisfaction and business outcomes.
Enterprise experience
From customer-facing digital services to mission-critical internal applications, we have extensive experience delivering secure, scalable solutions that integrate with complex enterprise technology environments.
Built around your business
No two organisations are the same. We tailor every application to your processes, objectives and existing systems, ensuring technology supports the way your organisation works today while preparing for future growth.
Secure & compliant
We embed security, accessibility and governance throughout the development lifecycle, helping organisations meet regulatory requirements while protecting users and sensitive information.
Scalable for the future
Our applications are designed to evolve. By adopting modular architectures, cloud-native services and API-first principles, we create platforms that can adapt to changing business requirements without costly redevelopment.
Long-term partnership
Our relationship doesn’t end at launch. We provide ongoing optimisation, application support and strategic guidance to ensure your digital platforms continue delivering value as technology and user expectations evolve.
Awards & accreditations
There’s more where that came from
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FAQs
Answers to common questions about web app development.
Web application development services cover the planning, design, development, testing, deployment and ongoing support of browser-based applications that help organisations deliver secure digital services, automate business processes and improve customer and employee experiences.
Unlike traditional websites, web applications allow users to interact with data, complete tasks and access business systems online. At CACI, our web application development services combine user-centred design, software engineering, cloud-native development and systems integration to create bespoke applications that are secure, scalable and built around your organisation’s needs.
Custom web application development enables organisations to create software that is tailored to their unique business processes, users and objectives, rather than adapting the business to fit standard software.
Unlike off-the-shelf solutions, bespoke web applications can integrate with existing CRM, ERP and third-party platforms, automate complex workflows and scale as your organisation grows. This provides greater flexibility, improved user experiences and a platform that can evolve alongside changing business and customer requirements.
We develop a wide range of bespoke web applications, including customer portals, employee portals, self-service platforms, workflow management systems, business applications, SaaS platforms, dashboards, booking systems and case management solutions.
Whether you’re developing a new digital service or modernising an existing platform, our applications are designed to improve operational efficiency, enhance user experiences and integrate seamlessly with your wider technology ecosystem.
Our web application development process combines discovery, user-centred design, software engineering and agile delivery to create secure, scalable applications that deliver measurable business value.
Projects typically begin with discovery, technical architecture and UX design before progressing through iterative development, testing, deployment and ongoing optimisation. Using Agile methodologies, DevSecOps, automated testing and continuous integration and deployment (CI/CD), we deliver reliable web applications that can adapt as your organisation evolves.
Yes. We help organisations modernise legacy web applications to improve performance, security, scalability and maintainability while reducing technical debt.
Depending on your objectives, this may include application re-platforming, refactoring, cloud migration, API development and integration, or migrating monolithic applications to modern cloud-native architectures. Our approach enables organisations to maximise existing technology investments while creating digital platforms that are ready for future growth.
We use a range of modern technologies to deliver secure, scalable web applications, selecting the most appropriate technology stack based on your business requirements, existing architecture and long-term objectives.
Our expertise spans frontend frameworks including React, Angular, Vue.js and Next.js, backend technologies such as .NET, Node.js, Java and Laravel, and cloud platforms including Microsoft Azure and Amazon Web Services (AWS). We also develop API-first, cloud-native applications using containerisation, microservices and DevSecOps practices where appropriate.
Security is embedded throughout our software development lifecycle, ensuring every web application is designed to protect users, business data and critical services.
We follow secure coding practices aligned with OWASP guidance and implement robust security controls including OAuth 2.0, OpenID Connect, Single Sign-On (SSO), multi-factor authentication (MFA), encryption and role-based access control. Combined with automated security testing, vulnerability management and DevSecOps practices, this helps organisations reduce risk while meeting governance and compliance requirements.
The timescale for custom web application development depends on the complexity of the solution, required functionality, integrations and business objectives.
Smaller applications can often be delivered within a few months, while larger enterprise web applications are typically delivered through phased, agile releases. This iterative approach enables organisations to prioritise functionality, gather user feedback and realise business value earlier while continuing to enhance the application over time.
The cost of web application development services varies depending on the application’s complexity, functionality, integrations, security requirements and ongoing support needs.
Rather than offering a one-size-fits-all solution, we work closely with organisations to understand their objectives, users and existing technology landscape before recommending the most appropriate approach. This ensures your investment is focused on delivering measurable business outcomes, long-term scalability and value.
A website is primarily designed to present information, while a web application enables users to interact with data, complete tasks and access business functionality through a web browser.
For example, a website might showcase products or services, whereas a web application could enable customers to manage accounts, submit applications, make bookings, complete transactions or collaborate with colleagues. Web applications typically include secure authentication, business logic, systems integration and personalised user experiences, making them a fundamental part of modern digital transformation.