1) Build automation 2) Meth user 
Tweak or tweaker can refer to: In drugs: In a computer related context: Other meanings: ...[build tool] Tweaker is an open-source, extendible software development build automation platform to consolidate the creation, management, and execution of scripts and custom utilities under a single location, intermix any languages (scripted or compiled) to perform tasks, allow common user interaction dialogs from all languages, and enable...
Tweaker is slang for an engineer's small screwdriver, used for fine adjustments.
slang for an engineer's small screwdriver, used for fine adjustments.