With out newest 2.24 update, you can now open and inspect Sketch files on macOS, Windows, Linux or even in your browser.
Our vision is to allow people to share design source files freely, all without having the design tools nor plugins installed. With this update we're getting closer again. Read more about it here.
Try it for yourself or share this with your dev team, they'll might welcome getting all specs and assets on their own without bothering you 🤓.
Thanks @Janis Andzans for stunning illustration work!