Web App Development
DevMations designs and builds web applications end to end — the interface customers use, the system behind it, and the hosting it runs on. Because the same team builds AI systems, any AI features in your product are engineered rather than demonstrated.
Also called Next.js · React · Node.js · full-stack development
Why teams call us about this
An AI feature is not a product. Somebody still has to build the accounts, the payments, the permissions, the admin screens and the hosting around it. When the team doing that does not understand the AI part, the joins show exactly where your customers touch them.
What you get out of it
- A product your customers can actually use, not a prototype
- You own it outright — code, documentation and deployment
- It stays fast and stable as you add customers
What you actually receive
Working software and documentation — not a report recommending that somebody else build it.
The whole product
Design, build, and launch — the customer-facing side, the system behind it, and getting it live. Not a stack of tickets for someone else to finish.
AI features that hold up
Built by the team that also builds AI testing, so any AI in your product has measurable quality on the day it launches.
Payments that work correctly
Stripe, PayPal and similar, handled properly including the awkward edge cases — the ones that quietly lose money when they are done carelessly.
Speed as a requirement
Load time and responsiveness are things we sign up to before launch, not something to look at afterwards.
A clean handover
Documentation, tests and instructions for running it, so your team or another developer can take over without depending on us.
The engagement
- 01
We agree the shape of it
How the information is structured, before anything is built. Most expensive rebuilds trace back to a decision made in the first fortnight.
- 02
We build in working pieces
Each one usable and reviewable, so you see real software early rather than a demonstration at the end.
- 03
We make it ready for real use
Testing, error handling, monitoring and speed work before launch — not after the first thing goes wrong.
- 04
We launch and hand over
Live, documented, and explained to whoever is looking after it next.
Under the hood
The specifics, for whoever on your side will be reviewing this. If that is not you, nothing below changes what you get — skip to the work.
- Stack
- Next.js App Router with React Server Components, Node.js or NestJS services, PostgreSQL or MongoDB, Redis for caching and queues, deployed to Vercel or AWS.
- Data modelling
- Schema and API contracts defined before implementation, with migrations versioned and reversible.
- Payments
- Webhook idempotency, replay handling and reconciliation — the parts that fail silently and expensively when skipped.
- Performance
- Core Web Vitals as acceptance criteria. Bundle budgets, image optimisation and query profiling as part of the build rather than a later pass.
- Delivery
- CI/CD with preview deployments per pull request, automated tests as a merge gate, error tracking wired up from day one.
What we use
- Next.js
- React
- TypeScript
- Node.js
- NestJS
- PostgreSQL
- MongoDB
- Redis
- AWS
- Stripe
- Tailwind CSS
Where we have done this
Live deployments you can open.
FinX Banking
A personal banking product with Plaid account linking and Dwolla transfers, covering multi-account balances, transaction history and bank-to-bank payments.
Open live site
DocuFlex
A collaborative document editor with authentication, multi-format upload, real-time editing and share links.
Open live site
I-CONTA
An accounting and tax consulting platform where clients upload documents, view their financial position and run tax calculations without waiting on their accountant.
Open live site
PriceWatch
A product price tracker that scrapes listings on a schedule, records price history and alerts users on drops.
Open live siteWeb Apps — questions
- Can you work on something we already have?
- Yes, and a good share of our work is exactly that. We start by reviewing what exists so the first change is informed rather than brave.
- Can you take over a project another developer started?
- Yes. Expect a short review phase first — inherited projects usually contain decisions nobody wrote down, and it is much cheaper to find those deliberately than during an incident.
- What happens after launch?
- Whatever suits you. We can hand over completely with documentation and training, or stay on for a support period. We deliberately do not build things that require us to stay.
- Who owns the code?
- You do, entirely, including anything AI-related we build. It lives in your accounts and your repositories from the start.
Thinking about Web Apps?
Describe what you have and what is going wrong with it. We will tell you what we would do first, and whether it is worth doing.
Book a call