Flutter on Artur Rios Lab

Netbank: A Banking System to Learn From

Thu, 22 Oct 2026 12:30:00 +0000

A complete banking system, built for learning purposes.

Technology

.NET on the back end
Flutter on the front end
Heimdall for authentication and authorization
PostgreSQL database

Platforms

Android
Linux
Windows
Web

What a complete bank covers

“Complete” is the part of the idea that needs a boundary. A real bank is hundreds of systems, so this is a suggestion of what Netbank should cover, chosen because each part teaches something a CRUD app does not. It moves no real money and connects to no real bank: every institution outside Netbank is simulated.

Merlin: A Reading Tracker

Thu, 22 Oct 2026 12:00:00 +0000

Merlin is an app to keep your readings.

Features

Search books from a public database
Track the books you are reading now, and read on the past
Write reviews on books

Platforms

Android
Web

Technology stack

One choice is already made: the app is built with Flutter, which builds the Android app and the web app from one Dart code base. How Flutter works, and what it is good and bad at, is covered in What Is Flutter?. What is left to decide is everything around it: where the books come from, where the readings and reviews are stored, and how the two platforms see the same library.

Web Apps

Wed, 21 Oct 2026 17:55:00 +0000

My interactive front ends are Flutter apps, and on the web they are a set of static files: HTML, JavaScript and WebAssembly. So the container that runs one is just a web server, small and stateless. Heimdall’s web app is the example.

Concern	Choice
Framework	Flutter, built for the web
Build stage	Debian with a Flutter SDK pinned by version and checksum
Runtime	nginx, unprivileged, with a read-only file system
Settings	Compiled in at build time, once per environment
API	Its own origin’s `/api/`, routed to the API by Traefik
Health	`/healthz`
Checks	Analysis and tests, and generated code checked in GitHub Actions

The image

The build stage installs Flutter itself, rather than starting from a community Flutter image, so the exact SDK version is pinned and its download is checked against a SHA-256 checksum. It builds as a non-root user, and fetches packages with --enforce-lockfile, so the build uses exactly the versions the repository was tested with:

Angular, React or Flutter? How They Compare and How to Choose

Tue, 20 Oct 2026 18:00:00 +0000

“Angular or React?” is one of the most common questions in front-end development, and “or Flutter?” is now often added to it. The question sounds like a choice between three brands of the same product. It is not. Angular is a complete framework for web applications; React is a library for turning state into UI, which needs a framework around it to make an application; Flutter is a toolkit for mobile, desktop, web and embedded apps that does not use the browser’s HTML at all, but draws every pixel itself. Each has been described in detail in this section: What Is Angular?, What Is React? and What Is Flutter?. This article puts them side by side and ends with a guide to choosing.

What Is Flutter? History, Architecture and How to Build With It

Tue, 20 Oct 2026 18:00:00 +0000

Most toolkits for building an app on more than one platform make a choice early on: either they wrap each platform’s own buttons, lists and text fields, or they run the app inside a web view. Flutter does neither. It ships its own rendering engine inside every app and draws every pixel of the interface itself, from the text to the scroll bars, on a canvas the operating system hands it. The same Dart code then runs on Android, iOS, the web, Windows, macOS and Linux, and on embedded devices through a custom host.