Too soon. Far, far too soon. 43 years old? Shit.

For those who aren't familiar with Mike on-site (he became less active in recent years): as well as his Q&A activity getting him to almost 100,000 rep (at the time of writing), he was also one of the most active users in back-end site upkeep stuff, thankless tasks such as ...

• Organising the great tag cleanup of 2015-16: Would we be interested in a concerted tag cleanup effort? and Tag Wars Episode I: Harry Potter and the Tag Cleanup and Tag Wars: The Science Fiction/Fantasy Tag Cleanup Event
• Further work on tagging policies: What is the correct usage of individual works tags vs. author tags vs. franchise tags? and Science Fiction and Fantasy Tagging Guidelines He became famous on the site for his thankless work on the tagging system.
• Drafting or igniting discussion on some of our most important site policies: Are *all* list questions off-topic? and Gorilla vs. Shark - a Longer Explanation and What is our actual policy on science questions? It could be said that all of our site's custom close reasons are thanks to him.
• Helping to manage the site blog after Stack Exchange stopped supporting blogs: What should we call our blog? and Look and feel of the new blog and Official Unofficial Blog Support Post Jack B. Nimble (the OP of this meta post) has been in charge of the blog for years, and CreationEdge (who deleted his SE account) hosts the new domain, but Mike valiantly volunteered to join the blog team.

Let his achievements live on in perpetuity. R.I.P.