Pretty fluffy piece, I'm not sure why it's so high. FB does have some pretty cool stuff though - I've been itching to play with React and GraphQL. One tangent

Pretty fluffy piece, I'm not sure why it's so high. FB does have some pretty cool stuff though - I've been itching to play with React and GraphQL. One tangential point I often think about is the importance of investing time in learning tools as a developer. What should the breakdown be? Should I spend 20% of my time "sharpening the ax" and the other 80% working on projects? Someone else in this thread pointed out that companies face some of the same questions. How many resources should be allocated to things like improving the build system or developing custom tools? Where is the break even point where time invested in tools starts saving time for developers working on core products?