Don't defer close on writable files

Go scheduler

Scheduling In Go : Part I - OS Scheduler
Scheduling In Go : Part II - Go Scheduler
Scheduling In Go : Part III - Concurrency

Errors

Errors are values
Error Handling In Go, Part I
Error Handling In Go, Part II
Don’t just check errors, handle them gracefully

Memory Management

An overview of memory management in Go

Golang Internals

Map Internals
How Interfaces work in Go

Reflections

The Laws of Reflection