The tl;dr

We should all be automating our image compression.

In 2017, image optimization should be automated. It's easy to forget, best practices change, and content that doesn't go through a build pipeline can easily slip. To automate: Use imagemin or libvips for your build process. Many alternatives exist.

Most CDNs (e.g. Akamai) and third-party solutions like Cloudinary, imgix, Fastly's Image Optimizer, Instart Logic's SmartVision or ImageOptim API offer comprehensive automated image optimization solutions.

The amount of time you'll spend reading blog posts and tweaking your configuration is greater than the monthly fee for a service (Cloudinary has a free tier). If you don't want to outsource this work for cost or latency concerns, the open-source options above are solid. Projects like Imageflow or Thumbor enable self-hosted alternatives.