go-exiftool makes it easy to extract metadata with exiftool and work with it in Go. There are currently no comparable native Go libraries with the breadth and depth of exiftool. In exchange for functionality there is a bit of a performance and a deployment penalty. Fortunately, these are minimal. exiftool only requires perl5, which is available by default on almost every platform. The performance overhead of using an external program can be mitigated in many ways (ie: parallel processing). Using Stayopen and Pool helper libraries makes metadata extraction pretty fast. On a 13" 2017 Macbook Pro I was able to extract metadata for 600 images in about 4 seconds.