Deploying Apex

Compile On Deploy

Each org’s Apex code is automatically recompiled before completing a metadata deploy, package install, or package upgrade. Compile on deploy is enabled automatically for production orgs and full sandboxes to ensure that users don’t experience reduced performance immediately following a deployment. You can’t disable the compile on deploy option in production orgs.

For developer sandbox, developer pro sandbox, partial copy sandbox, developer, trial, and scratch orgs, this feature is disabled by default. To enable, select the Perform Synchronous Compile on Deploy option under Apex Settings in Setup. Deselect this option if you want to disable the feature in full sandboxes.

With the Compile on Deploy feature, deployments to the org invoke the Apex compiler and save the resulting bytecode as part of the deployment. For example, if you deploy a custom field, all the classes that use that custom field are recompiled. A minimal increase in deployment times can occur, but Apex doesn’t need to be recompiled to process subsequent requests. The slight increase in deployment time can, in fact, mitigate performance issues for currently active users or processes. Consider enabling this feature in sandboxes or scratch orgs shared by multiple users for functional testing or used by continuous integration processes.