Hello, I'm Cos

I'm an engineer, operator, and entrepreneur.

Building Accrual. Previously was the CTO at Brex, where I scaled the company from 40 to over 1,000 employees and hundreds of millions in annual revenue. I've also worked at Stripe as an early engineer and manager, building core global payments infrastructure, and launching the Stripe Terminal product. I started my career at Microsoft, working on the early versions of Azure and Office365.

Moving places has helped me embrace changes of varying magnitudes. I've so far lived in the following cities:

• Born in Bucharest, Romania
• Exchange student in Deatsville, AL
• University in Philadelphia, PA
• Vancouver, BC
• Seattle, WA
• San Francisco, CA
• Los Angeles, CA

Some opinions and beliefs I've formed over time:

• Everything compounds
  • Investing in something, and then letting it grow, leads to surprising moats
  • Conversely, a series of poor decisions or constant tacking is tremendously difficult to recover from
• Time is our most precious resource
  • At least for now, you can't buy more, nor manipulate
  • Memories are more valuable than vast majority of material goods
• Speed matters
  • In a multi-step problem, reduce the long-pole, recursively
  • Everything can move faster, though you should focus on accelerating the things that move the needle
  • How fast you act and respond is a signal to others
• Smaller teams are better
  • There's less overhead, leads to faster decisions, and is more fun for everyone involved
  • Scarcity of resources increases focus and leads to better prioritization
  • The failure modes of under-staffing tend to be much less severe than those of over-hiring
• Extreme positions often lead to suboptimal outcomes
  • Most often you're simply balancing multiple variables, which leads to various tradeoffs
  • People tend to over-simplify problems (also people, i.e. "person X is good/bad")
  • In conflict, the truth is somewhere in the middle
  • Few situations are zero-sum, and you should strive to avoid them
• EQ tends to be underrated
  • Individuals have unique reactions, so no matter how great one is at pattern-matching, outcomes are highly dependent on the mix of individuals involved
  • Being able to read the room can give you a significant advantage, especially in tech
  • Learn to trust your instincts, and constantly fine-tune them with new experiences