Rob Janssen (RobIII)

Is this password migration strategy secure?

One potential consideration is that combinations of security principles may have unintended vulnerabilities.

Instantly migrate to a secure password hashing scheme

So your site uses terrible password hashing scheme H1 (perhaps MD5), and you want to migrate to secure password hashing scheme H2 (preferably scrypt, but possibly bcrypt or PBKDF2). The standard migration approach is to upgrade users as they log in and enter their password.

Why JSON in PostgreSQL is Awesome

Recently a commenter on Hacker News questioned the usefulness of the JSON data type in PostgreSQL. At the time I posted a brief response, but I have decided to take the time to write up a more detailed explanation here as I believe the JSON data type provides a significant benefit to developers.

10 things I hate about Git

Git is the source code version control system that is rapidly becoming the standard for open source projects. It has a powerful distributed model which allows advanced users to do tricky things with branches, and rewriting history.

Why you need a “Definition of Done”

OH Customer: Strange, I don’t see the new merged list feature we discussed about last month. Developer: No, it is not there yet. Customer: But it was marked “done” in our last meeting? Developer: Yes, sure, it is done, it is just not deployed yet. Customer: Ah.

Animated GIFs the Hard Way

When doing the new website for the Sublime Text 2.0 launch, instead of just screenshots, I wanted to have animations to demonstrate some of its features. One of the criteria was that the animations should work everywhere, from IE6 to an iPad.

Distributed SQL Query Engine for Big Data

What is Presto? Presto is an open source distributed SQL query engine for running interactive analytic queries against data sources of all sizes ranging from gigabytes to petabytes.

The Art of Hashing

In Binary Search Trees I, II, and III, we considered methods for efficient searching of an ordered collection by using key comparisons. While these methods were indeed very fast, they were limited to O(log N) performance due to the comparison tree inherent in the data structure.

Hardening Perl's Hash Function

In 2003 the Perl development community was made aware of an algorithmic complexity attack on the Perl's hash table implementation[1]. This attack was similar to reports over the last few years of attacks on other languages and packages, such as the Java, Ruby and Python hash implementations.

How to program unreliable chips

As transistors get smaller, they also become less reliable. So far, computer-chip designers have been able to work around that problem, but in the future, it could mean that computers stop improving at the rate we’ve come to expect.