Oliver Sand

Hello, I’m a full stack software developer from Hamburg, Germany interested in cloud architecture and open source software development.

I have a broad area of interests including, but not limited to:

User interfaces build with web technologies like React, TypeScript, and NodeJS,
Cloud architecture, Kubernetes or serverless, as well as related security aspects,
Developer Experience (DX),
3D rendering with WebGL,
Maintaining and contributing to open source software,
And I’m a big fan of the Dart language due to its simplicity, type safety, and tooling.

I contributed to several open source projects in the past, including backstage/backstage and google/vector_math, but I also tend to make small contributions to projects that I use. Beside that, I own some small projects like tentaclelabs/prometheus_client, a Dart implementation of the Prometheus client library.

2021
Senior Software Engineer at Nordeck IT & Consulting
Nordeck is building communication tools based on Matrix, Element and Jitsi. I work on Project Phoenix, the workplace for the public sector in north Germany. It’s based on the matra “public code for public money” — bringing a modern workplace that is autonom, independent, and where users have control over their personal data.
2018
Software Engineer at SDA SE
At SDA SE I work on accelerating the digitalization of the insurance sector by building a platform and an ecosystem that brings modern services to customers. This included technical concepts as well as the groundwork for the microservice architecture of the platform. I could gather experience in different areas, including frontend and backend development, DevOps and operations.
To share knowledge and teach other developers in the ecosystem we founded the site sda.dev providing documentation and teaching concepts. Lately I’m contributing on the Spotify founded CNCF project Backstage that we use to provide an internal developer portal and catalog of the services available in the ecosystem.
backstage.io: https://backstage.io/
2016
Software Engineer at Interautomation Deutschland GmbH
Interautomation is building software for organizing processes in the public transport sector which has exciting technical challenges in an interesting business domain. I worked on both a web based control center software and a mobile Web app that provides the train conductor an overview about his schedule, delays, and passenger counts.
2015
Research Associate at Fraunhofer IOSB-INA
My short scientific career after my university studies. Associated to my master’s thesis I worked on assistive systems in manually assembly. Providing guidance for a worker in complex assemblies is an interesting UX topic, but also included technical challenges like hand tracking with depth cameras and a projection based user interface at the workstation. Here is a small demo:

Oliver's Posts

Range queries in Firestore

January 14, 2024

I like Firestore because it's an easy-to-use database. Especially because it's easy to build queries that are just fast. It's designed to work at scale - by providing queries that have a constant time, regardless of the query conditions. But if you have worked with Firestore before, you will know that this limits the types of queries you can do. This can make range queries, for example for calendar applications, a challenge.

Oliver Sand

Scale re-orderable lists

December 31, 2023

Creating a UI where a user can manually reorder items based on their needs is neat, but can be quite challenging to implement in the backend. One need to store the order of the items somehow. There are different approaches to doing this, but each of them has trade-offs when it comes to performance and scalability. In this post I want to explain my scenario, compare them, and choose the best implementation.

Oliver Sand

Be careful with performance.measure

May 3, 2023

I recently helped a team improve the performance of one of their services. They had already invested some time, but over time the performance was getting even worse! Their Node.js service was suffering from slow response times. At some point, the team added performance tracing using performance.mark() and performance.measure() to understand why the response time was so long. Little did they know that this would make things even worse…

Oliver Sand

Tools for drawing diagrams in Markdown

January 19, 2023

Markdown is a great format. I use it a lot for documentation. It's much easier to keep documentation up to date by keeping it close to the code. Sure, Markdown has limited formatting features, but it helps to focus on the essential part, the content. But there is one feature missing: Drawing diagrams.

Oliver Sand

react-beautiful-dnd is ugly

July 7, 2022

react-beautiful-dnd is a great package for building complex drag and drop behaviors of lists. If you want to reorder the items in a list or move them between lists, this is the go-to package. But the package has a problem: Atlassian has limited its maintenance to security fixes.

Oliver Sand

I have bad luck with Cypress

May 14, 2022

Testing is all about being confident that your changes to the software can be deployed to production without problems. While unit or integration tests help you to test details — like the results of a calculation, or whether two parts of your system are working together — you don't know whether all parts of your system are working together as they should. Systems are getting ever more complex and we try to cope with that by splitting it up into parts so that we can handle them or distribute the complexity over multiple teams. Teams develop and deploy small, loosely coupled Microservices that reassemble a bigger system. How do you know that everything works together and that a user can use it? This is where End-to-end (e2e) testing comes into play. And Cypress can be a nice tool for that.

Oliver Sand

Draw a pattern along a path using SVG

April 2, 2022

Recently I wanted to create the effect of a cable for an application I'm working on. The cable should have a textile look, similar to a rope, which is quite common right now (for example the charging cable of the current MacBook Pro). I'm using SVG for rendering, so applying a pattern to a stroke path should be easy, right?

Oliver Sand

prometheus_client, a Prometheus Implementation for Dart

March 4, 2022

We recently released the stable 1.0.0 release of our prometheus_client package — a way to expose Prometheus metrics in your Dart application. It's inspired by similar packages like the official client_java for Java or the community package prom_client for Node.js. We have several Microservices written in Dart where we use the package to provide observability. I want to share the experience we had while developing the package.

Oliver Sand

Choosing dependencies – Snyk Advisor

February 1, 2022

I recently wrote about my indicators that I use while choosing dependencies in the NPM ecosystem. After writing the post I thought, can you automate these steps to provide a quick view on package health? One tool that does that is the Snyk Advisor. I tried the advisor and want to summarize my experience.

Oliver Sand

depcheck – Linting dependency usage

January 27, 2022

In my previous post, I wrote about choosing dependencies wisely. The NPM ecosystem is known for its small packages with a lot of dependencies. You can quickly lose track about your dependency usage. Do you have all dependencies configured correctly? Are all of your dependencies still in use? I want to present you depcheck, a small utility to keep track of your dependency usage.

Oliver Sand