Slack today will announce its first-ever chief financial officer: Allen Shim, who had been serving as the company's senior VP of finance and operations. Shim has been with Slack almost since its founding (employee #20), and has former Wall Street experience as an equity research analyst with both Sanford C. Bernstein and Citigroup.

Why it matters: This comes on top of Slack's addition of Sarah Friar last year as its first independent board member, and reads like the sort of internal professionalization that can set up an IPO.