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@soarez
soarez / ca.md
Last active April 24, 2025 12:51
How to setup your own CA with OpenSSL

How to setup your own CA with OpenSSL

For educational reasons I've decided to create my own CA. Here is what I learned.

First things first

Lets get some context first.

@zsup
zsup / ddd.md
Last active May 6, 2025 10:50
Documentation-Driven Development (DDD)

Documentation-Driven Development

The philosophy behind Documentation-Driven Development is a simple: from the perspective of a user, if a feature is not documented, then it doesn't exist, and if a feature is documented incorrectly, then it's broken.

  • Document the feature first. Figure out how you're going to describe the feature to users; if it's not documented, it doesn't exist. Documentation is the best way to define a feature in a user's eyes.
  • Whenever possible, documentation should be reviewed by users (community or Spark Elite) before any development begins.
  • Once documentation has been written, development should commence, and test-driven development is preferred.
  • Unit tests should be written that test the features as described by the documentation. If the functionality ever comes out of alignment with the documentation, tests should fail.
  • When a feature is being modified, it should be modified documentation-first.
  • When documentation is modified, so should be the tests.
@jeromer
jeromer / compassbearing.py
Last active May 6, 2025 20:14
compass bearing between two points in Python
# LICENSE: public domain
def calculate_initial_compass_bearing(pointA, pointB):
"""
Calculates the bearing between two points.
The formulae used is the following:
θ = atan2(sin(Δlong).cos(lat2),
cos(lat1).sin(lat2) − sin(lat1).cos(lat2).cos(Δlong))
@nifl
nifl / grok_vi.mdown
Created August 29, 2011 17:23
Your problem with Vim is that you don't grok vi.

Answer by Jim Dennis on Stack Overflow question http://stackoverflow.com/questions/1218390/what-is-your-most-productive-shortcut-with-vim/1220118#1220118

Your problem with Vim is that you don't grok vi.

You mention cutting with yy and complain that you almost never want to cut whole lines. In fact programmers, editing source code, very often want to work on whole lines, ranges of lines and blocks of code. However, yy is only one of many way to yank text into the anonymous copy buffer (or "register" as it's called in vi).

The "Zen" of vi is that you're speaking a language. The initial y is a verb. The statement yy is a simple statement which is, essentially, an abbreviation for 0 y$:

0 go to the beginning of this line. y yank from here (up to where?)