This is the directory which holds all the common stuff required by all the different services.

The structure within this is folder is something like this:

config.go - holds all the config items util.go - holds the utlity stuff like creating tchannel, boot strapping ringpop, etc. *types.go - holds the types for the specific interface (eg: servicetypes.go - holds the object and interface definition for all common stuff used by our services) *.go - business logic implementing the interface (eg: service.go - implements the methods specific to servicetypes.go)