After some turmoil at senior levels of Snapchat’s parent Snap last year, things have stabilized considerably this year. Most of the crucial management roles have now been filled, in time for the company’s expected IPO in early 2017.

Earlier this year Snap made interim CFO Drew Vollero permanent, reporting to CEO Evan Spiegel instead of Chief Strategy Officer Imran Khan, as Mr. Vollero had been doing. It also hired veteran ad salesman Jeff Lucas away from Viacom to be head of sales, a position unfilled since the departure of Mike Randall in early 2015.

And yet, the youth of the company is reflected in the ad hoc nature of its organizational structure, detailed in this graphic.