LB: Reimplementing trivial subsets of libraries is highly underrated. If all you need is a few lines of functionality, please don't link to a whole new dependency just for that. It's not worth it. I guarantee you're creating more maintenance burden with the dependency and the build/packaging/upgrade/compat churn that comes with it than you would be if you just vendored or reimplemented the little bit of code you need. 

 What is the most non-trivial trivial bit of functionality in your opinion?  Where is your cutoff?