Ktor on Jamie Craane personal blog

Multi-Tenancy With Postgres Row-Level Security in Ktor

Thu, 09 Jul 2026 00:00:00 +0000

Introduction

Moxie IT (the company I co-own) developmed a time tracking and invoicing tool called MinuteMint as an alternative to Harvest. It runs in production and supports multi-tenancy from the first migration: every client, project, time entry and invoice belongs to exactly one tenant.

That raises a question you have to answer on day one, because it is expensive to answer later:

Where does tenant isolation actually live?
What happens when a developer forgets to apply it?
How do you prove, in a test, that a tenant cannot see another tenant’s rows?

The default answer in most codebases is “in the query”. I think that is the wrong place.

Integrating Firebase auth in server side Thymeleaf app

Thu, 12 Jun 2025 00:00:00 +0000

This blog post explains how to implement server-side authentication with Firebase in a Kotlin Ktor application using Thymeleaf templates. This approach is particularly useful for admin panels or dashboards where you want to leverage Firebase Authentication while rendering server-side HTML. By leveraging Thymeleaf (or other server-side templates for example Freemarker), may shorten the time-to-market for these kind of dashboard compared to full fledged Javascript frameworks like Angular or React.

Integrating Firebase JWT token verification in Ktor - Part 2

Wed, 15 Jan 2025 00:00:00 +0000

Part 2: Integrating Firebase Users into Your Database with Ktor

In the first part of this blog series, we explored how to integrate Firebase JWT authentication into your Ktor application. Besides creating accounts and logging in, we also want to store a reference of the Firebase user in our own database. This way, data can be associated with a specific user.

In this post, we will look at how to integrate your Firebase users in your own application database. This article will cover using custom tokens, context receivers, and the Exposed SQL library to implement this functionality.

Integrating Firebase JWT token verification in Ktor - Part 1

Wed, 11 Dec 2024 00:00:00 +0000

Integrating Firebase JWT token verification in Ktor - Part 1

As applications become more complex and security becomes a priority, choosing the right tools to handle authentication is crucial. Today, we’ll explore how to integrate Firebase JWT (JSON Web Token) authentication in a Ktor server application. This blog post will cover the core setup and implementation details required to ensure secure handling of JWTs in a Ktor application.

Introduction to Ktor and Firebase Authentication

https://ktor.io is a lightweight framework for creating web applications in Kotlin, known for its simplicity and flexibility, you will find no magic here. Firebase Authentication provides backend services, easy-to-use SDKs, and ready-made UI libraries to authenticate users to your app. It supports authentication using passwords, phone numbers, and popular federated identity providers like Google, Facebook, and Twitter.

Ktor on Jamie Craane personal blog

Multi-Tenancy With Postgres Row-Level Security in Ktor

Introduction

Integrating Firebase auth in server side Thymeleaf app

Server-Side Login with Firebase in Thymeleaf Templates

Integrating Firebase JWT token verification in Ktor - Part 2

Part 2: Integrating Firebase Users into Your Database with Ktor

Integrating Firebase JWT token verification in Ktor - Part 1

Integrating Firebase JWT token verification in Ktor - Part 1

Introduction to Ktor and Firebase Authentication