Development / Custom Applications

When off-the-shelf doesn't fit your business.

Some problems require custom solutions. We architect and build web applications that do exactly what your business needs: nothing more, nothing less.

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Custom Applications

Custom web application development is the design and building of software that runs in a browser and does a job no off-the-shelf product does: client portals, internal tools, booking and quoting systems, and software-as-a-service products. It covers architecture, database design, authentication, integrations, deployment and the maintenance that follows.

GrossiWeb is a web development agency founded in 2006 and based in Atlanta, Georgia, serving Raleigh, Los Angeles and businesses nationwide. Its custom application service builds client portals, internal tools and SaaS products on Next.js, TypeScript and Supabase, from architecture and scoping through deployment and ongoing support, and is quoted after a scoping call.

What this means for your business

Custom applications are investments in operational advantage. When the right tool doesn't exist, we build it: using Next.js, TypeScript, and Supabase for reliability, scalability, and speed of development. From client portals to internal tools to full SaaS products.

Deliverables

What you actually get.

Architecture & scoping

Technical architecture, database design, and detailed specification before any code is written.

Full-stack development

Frontend, backend, database, authentication, and third-party integrations: we own the whole stack.

Deployment & ongoing support

Vercel/AWS deployment, monitoring setup, and ongoing maintenance and feature development.

Why it matters, in numbers

Most of the web runs on WordPress, and it shows in the numbers

40.2%

of all websites run on WordPress, which is 58.8% of sites with a known content management system

W3Techs, 2026

11,334

new security vulnerabilities found in the WordPress ecosystem in 2025, 91% of them in plugins

Patchstack, 2026

46%

of those vulnerabilities had no fix from the developer by the time they were publicly disclosed

Patchstack, 2026

63.7%

of ecommerce sales in August 2026 were placed on a mobile device; desktop took 34.7%, tablets 1.6%

IRP Commerce, 2026

Sites passing all Core Web Vitals, by CMS

Shopify77%
Wix74%
Squarespace69%
Drupal61%
Joomla55%
WordPress45%
Share of mobile sites with good scores on all three Core Web Vitals in 2025, for the six largest CMS by site count. Fewer than half of WordPress sites pass; results there depend on the theme and plugins chosen. Source: HTTP Archive Web Almanac, 2025.
How it works

What you need to know before you start.

When does a business need a custom application?

A business needs a custom application when the process it runs is a competitive advantage that no existing product fits, or when the cost and workarounds of forcing several off-the-shelf tools together exceed the cost of building one that matches the process. GrossiWeb checks the second condition in scoping and will recommend an existing product where one fits. Typical builds are client portals, internal tools that replace spreadsheets, and first versions of SaaS products.

How does GrossiWeb build custom applications?

GrossiWeb writes the technical architecture, database design and a detailed specification before any code, then builds the full stack: front end, back end, database, authentication and third-party integrations on Next.js, TypeScript and Supabase. Deployment is on Vercel or AWS with monitoring set up, followed by ongoing maintenance and feature development. The code lives in the client's own repository and the hosting accounts are in the client's name from the first commit.

How much does custom web application development cost?

GrossiWeb quotes custom applications after a scoping call, because the price is set by the number of user roles, screens, integrations and business rules rather than by a package. For context, published 2026 guides put a Next.js web application at $30,000 to $150,000 or more (WebHelp Agency, 2026) and a small business web app at $35,000 to $75,000 (PerfectionGeeks, 2026).

FAQs

Questions people ask

What does a Next.js build cost and how long does it take?

Published 2026 guides put a Next.js marketing site at $5,000 to $10,000 and a web application at $30,000 to $150,000 or more (WebHelp Agency, 2026); GrossiWeb quotes each application after scoping fixes roles, screens and integrations, with the timeline set in the same quote. Marketing sites are priced on the web development page, and AI features are scoped under AI builds.

Is Next.js still relevant, or are developers moving away from it?

Next.js remains the most widely used React framework for production sites and applications, with active releases from Vercel and a large hiring market; US React developers bill $100 to $150 an hour for senior work (Index.dev, 2025). GrossiWeb keeps its applications portable across hosts. The Next.js versus WordPress article covers the framework choice for content sites.

Who maintains it after launch?

GrossiWeb offers a maintenance and support plan from $250 a month covering hosting management, security and framework updates, monitoring and a monthly allowance of changes; larger feature work is quoted. Because the code and hosting accounts are in the client's name, an in-house team or another developer can also take over. Applications that need automated workflows can add workflow automation.

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Outcomes

Industries

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