Here’s a quick look at a few things we’ve done in the past few months to make sure Expensify runs faster than a <insert inappropriate joke here>.
Cache, Cache, Cache
Before (dashed) and after (solid blue) chart of API response times – from New Relic
The biggest change we’ve made to speed up our API was introducing a global caching layer, aware of the relationships between the data we handle, and capable of prefetching resources in bulk when necessary. This has reduced the read load on our database server by around 25% (!), freeing resources to serve more customers at any time, especially at peak load. The API is used by all of our apps, including expensify.com – so the benefits of this can be perceived across all of our services. Continue Reading…
