What is wrong with UUIDs and GUIDs

Universally Unique Identifiers (UUIDs) otherwise known as Globally Unique Identifiers (GUIDs) are 128-bit numbers that are often used to identify information. In its canonical representation, a UUID looks like this: 2205cf3e-139c-4abc-be2d-e29b692934b0.

The Wikipedia entry for Universally Unique Identifier () says that they are "for practical purposes unique" and that "while the probability that a UUID will be duplicated is not zero, it is so close to zero as to be negligible." Wikipedia then does the math and shows that if 103 trillion UUIDs are generated, the chance of duplication among them is one in a billion.  

Despite the infinitesimal chances of receiving a duplicate UUID, there exist programmers out there who are afraid of that actually happening, and who will not hesitate to blame duplicate UUIDs as potentially responsible for an observed malfunction in the software they are developing rather than admit that there is a bug in their code. Clearly, these folks do not understand the meaning of infinitesimal.

Great.  Now, let me tell you why I hate UUIDs.

The 32 hexadecimal digits that make up a UUID have a higher concentration of entropy than anything else that I deal with during a regular working day.  (It helps that IntelliJ IDEA spares me from having to see git commit hashes.)  This is to say that the overwhelming majority of all the entropy that I am exposed to nowadays is due to seeing UUIDs. This was not happening in the days before the UUID; entire weeks could pass without seeing something as hopelessly nonsensical as a UUID, requiring me to coerce my brain to ignore it because "there is no sense to be made here". The higher the entropy of the visual stimulus we are exposed to, the higher the cognitive effort required to process it, even if just to dismiss it as un-processable. This makes UUIDs very tiresome to work with. When looking at a table of columns, the UUID column is always the angry column.


6 videos from TechSummit Amsterdam 2017 (Jun 1st)

A couple of weeks ago some of us went to the TechSummit conference organized by LeaseWeb.  Here is a list of the talks that I attended, along with a short description for each.

The first presentation was “Shaving my head made me a better programmer” by Alex Qin, which was about what it is like to be a woman, and specifically a programmer, in the U.S. tech industry.  (And in the University before that.)  She talked about the inequality, the sexism, and the harassment.   She mentioned that she once gave a talk in a really big conference about accessibility in the U.S., and afterwards she was asked “How do I talk to women at bars?”  The head-shaving part refers to how changing her appearance resulted in being taken more seriously.  It was quite an interesting talk, though I suspect that in Amsterdam, she was to a large extent preaching to the choir.



My notes on the Fielding Dissertation (REST)

These are my notes on Roy T. Fielding's famous Ph.D. dissertation "Architectural Styles and the Design of Network-based Software Architecture"

What follows are excerpts from the dissertation, with my notes usually in parentheses.

Roy Thomas Fielding is: chief Scientist in some tech company; Chairman, Apache Software Foundation; Visiting Scholar, W3C @ MIT CS Lab; etc; Publications, Honors, Awards, Fellowships etc. Involved in the authoring of the Internet standards for the Hypertext Transfer Protocol (HTTP) and Uniform Resource Identifiers (URI).


"The World Wide Web has succeeded in large part because its software architecture has been designed to meet the needs of an Internet-scale distributed hypermedia system."
(He makes it sound as if it was designed this way on purpose.)

"In order to identify [...] aspects of the Web that needed improvement and avoid undesirable modifications, a model for the modern Web architecture was needed to guide its design, definition, and deployment."

(So, he admits the need to build a model after the fact.)

"An architectural style is a named, coordinated set of architectural constraints."