A good hands-on introduction to service workers from Mariko.
The Fallacies of Distributed Computing (Applied to Front-End Performance) – CSS Wizardry – CSS Architecture, Web Performance Optimisation, and more, by Harry Roberts
Harry cautions against making assumptions about the network when it comes to front-end development:
Yet time and time again I see developers falling into the same old traps—making assumptions or overly-optimistic predictions about the conditions in which their apps will run.
Planning for the worst-case scenario is never a wasted effort:
If you build and structure applications such that they survive adverse conditions, then they will thrive in favourable ones.