Rob Janssen

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Don’t Hash Secrets

Building secure systems is difficult. It would be nice if we had a bunch of well-designed crypto building blocks that we could assemble in all sorts of ways and be certain that they would, no matter what, yield a secure system overall.

95% engineers in India unfit for software development jobs, claims report

NEW DELHI: Talent shortage is acute in the IT and data science ecosystem in India with a survey claiming that 95% of engineers in the country are not fit to take up software development jobs. According to a study by employability assessment company Aspiring Minds, only 4.

The 640 K Barrier

There was a demon in memory. They said whoever challenged him would lose. Their programs would lock up, their machines would crash, and all their data would disintegrate. The demon lived at the hexadecimal memory address A0000, 655,360 in decimal, beyond which no more memory could be allocated.

Temporal coupling and Immutability - Enterprise Craftsmanship


Luckily, I know this about myself. This allows me to consciously engineer my life so that despite having the emotional maturity of a heroin-addicted lab rat, I’m occasionally able to get things done. I waste a lot of time on Reddit.

Ten SQL Server Functions That You Hardly Use But Should

In order to see what rows are in table 1 and not in table 2 and vice versa you can do 2 left joins, 2 right joins or 1 left and 1 right join. To get the rows that are different you can use BINARY_CHECKSUM.

Solving the Water Jug Problem from Die Hard 3 with TLA+ and Hypothesis

This post was originally published on the author’s personal site. It is reproduced here with permission from the author. In the movie Die Hard with a Vengeance (aka Die Hard 3), there is this famous scene where John McClane (Bruce Willis) and Zeus Carver (Samuel L.

Distributed count(distinct) with HyperLogLog on Postgres

Running SELECT COUNT(DISTINCT) on your database is all too common. In applications it’s typical to have some analytics dashboard highlighting the number of unique items such as unique users, unique products, unique visits.

Interesting data structures: the BK-tree

A BK-tree is a tree data structure specialized to index data in a metric space. A metric space is essentially a set of objects which we equip with a distance function \(d(a, b)\) for every pair of elements \((a, b)\).

A Powerful F# Library Shows How S-Expressions Can Beat XML and Json

People used to love XML, especially those in the Microsoft camp. XML represented a powerful enabling technology for programmers of that day?—?data-driven programming without plain text files. Out of this love for XML came many technologies on which we still rely.

This Read-It-Later-list is just that, bookmarks of stuff I intend to read or have read. I do not necessarily agree with opinions or statements in the bookmarked articles.

This list is compiled from my Pocket list.