Linux, apache and mysql is a hit combination that I mostly use as my backend. For version control I mostly prefer git.
Solr is a very effective backend search engine. I have worked on at least two projects in which I used solr as a backend search engine with almost a million search entities. I have used it with Drupal and ASP.NET
I am working in Drupal for last three years. I have worked from module development to theme development to unit testing. Ping me and I won’t disappoint you.