[warp]

I always try to find a library which does what I need before writing one myself. However, I rarely consider proprietary libraries.

With open source or free software libraries I can quickly get some idea of how well-written the library is, and how well it can be extended in the directions I need it it to.

In rare cases I might pick a propietary library for a project at work, but even then I only pick those for which I get the source code. When a client calls with some issue which needs an immediate fix, I can actually dive in and fix things.