Author: Marcel Waldvogel

  • Array Thickening: More can be less

    Array Thickening: More can be less

    When turning flexible file formats into data structures, the consensus seems to be to avoid using arrays whenever possible. However, more arrays may reduce code and coding errors. A plea against the extinction of arrays.

  • vcard4-ts: A TypeScript-first vCard parser

    vcard4-ts: A TypeScript-first vCard parser

    TypeScript is the amiable and helpful sibling of JavaScript, always there for you, whether you currently do want type safety or you don’t. So it was only natural to use it to make handling digital business cards easier. vCard4-ts is the result of this attempt.

  • CompanyON: Serving as gutSTEIN

    CompanyON: Serving as gutSTEIN

    Our gift card solution for regional brick-and-mortar stores and restaurants has been successfully used in Stein am Rhein for almost a year. As of today, the local version of our gift card for Stein am Rhein, provided by the regional business association, also has a local name: gutSTEIN. The card has become an important asset…

  • Contact Tracing — Quo Vadis?

    Contact Tracing — Quo Vadis?

    How much we are all looking forward to returning to normal lives: Meeting friends, hugging family, a cool beer, culture. After more than a year, we really deserve it! However, there are still roadblocks in the form of a bloody virus and the countermeasures. Anyone promising a quick end is hailed as a saviour. (This…

  • Electronic Vaccination Certificate: Eureka! Eureka?

    Electronic Vaccination Certificate: Eureka! Eureka?

    When I was reading the original “Spiegel” article on the German Electronic Vaccination Certificate, I was fascinated.

  • Generating Multi-Architecture Docker Images Made Easy

    Generating Multi-Architecture Docker Images Made Easy

    Docker is cool and portable, but distributing Dockerfiles comes at a disadvantage: The demands on the build environment are high. Distributing Docker images solves this, but building them for an architecture other than your CPU architecture seems complicated. Here is a simple solution.

  • HomeCA: Scalable Secure IoT Network Integration

    HomeCA: Scalable Secure IoT Network Integration
  • A brief history of time(stamping)

    A brief history of time(stamping)

    When I tell people about timestamping, they often react with, “Ah, yes, that Blockchain thing”. However, timestamping is as old as civilisation and has some interesting properties it gains from non-Blockchain applications. So let’s go back a few millenia first.

  • Timestamping: Why should I care?

    Timestamping: Why should I care?

    Timestamping documents is the basis for many forms of trust and evidence. As such, it is a building block for contracts and agreements, and dispute resolution.

  • A SIP library is born

    A SIP library is born

    Inspired by Andrijan Möcker’s “Überallklingel” (Everywhere Bell), I decided to create my own. However, I wanted to use it with a motion sensor and therefore to be able to turn it off and on again, when necessary. I also felt that using Asterisk was overkill and it could be done quickly and much easier with…