Napkin Math #20: Scaling Causal's Spreadsheet Engine from Thousands to Billions of Cells: From Maps to Arrays
Earlier this year, I spent a few weeks working with Causal on their core spreadsheet engine. Causal is a spreadsheet built for the 21st century to help people work better with numbers. Behind Causal’s innocent web UI is a complex calculation engine — an interpreter that executes formulas on an in-memory, multidimensional database.
For the fellow nerds out there who like to use probability distributions in their spreadsheets, this is something Causal can do as well. You can type 10 to 100 in a cell, and it'll do monte carlo simulations across all your cells to give their distributions. Pretty cool.
I worked with them on how we could scale their engine from millions to billions of cells. The short of it is: by moving the core data structure from maps to arrays. 😅
Read the full napkin math article here!
P.S. I have some spare time over the summer, if there's a type of post you'd love to see, reply with your suggestions!