Technology used by startups

(Note: the ratios of the lengths of blue/orange/red bars are 1:3, 1:1, and 2:1.)

Observations:

• For great companies, the most popular languages are Javascript, Ruby, Python, and Java.
• For okay companies, the most popular languages are Javascript, Ruby, PHP, and Java.
• The likelihood that PHP is being used is strongly anti-correlated with company quality.
• The better the company, the more likely it is to be using modern and/or functional programming languages (i.e. Go, Scala, Haskell, Erlang, Clojure).

This chart shows a combination of web frameworks (Rails, Django), Javascript Libraries, and HTML/CSS.

• Ruby on Rails is super popular.
• HTML5 is dominating HTML.
• CSS is still dominating CSS3.
• The better the company, the less likely it is to use Bootstrap.

• MySQL, Mongo, and Postgres dominate the database side.
• Redis is much more popular than memcached.
• The better the company, the less likely it is to build on top of Microsoft's products (SQL Server).

• Developing for iOS is slightly more popular than developing for Android
• The gap widens as company quality increases.
• Windows Mobile (which is not present in the chart) is 30x-50x less popular than iOS and Android among good/great companies.

• AWS and Heroku dominate.
• The better the company, the more likely it is to use IaaS (e.g. AWS) instead of PaaS (e.g. Parse)
• The better the company, the less likely it is to build on top of Microsoft's products (Azure).

(Note: the sample size here was small because DevOps tools were rarely mentioned on AngelList profiles)

• Elasticsearch dominates this category.

(Note: the sample size here was small because APIs were rarely mentioned on AngelList profiles - especially for good/great companies.)

• I was surprised that there's no clear correlation between quality of company and usage of sophisticated technologies like machine learning or computer vision.