When Facebook acquired WhatsApp back in 2014 for  $19 Billion it had 55 employees .

This was an insane $350 Million per employee and one of the biggest payouts in the history of venture capital.

With just 55 employees, the WhatsApp team was able to create technological marvels in both scale and efficiency by doing per-day volume at 19 billion messages sent and 34 billion received  (Feb 2014 - 450 MAU) .

They achieved this by ruthlessly prioritizing the core functionalities and outsourcing anything else possible. This is a case study for all startups building their platform in early stages.