ENABLE_ORYX_BUILD vs. SCM_DO_BUILD_DURING_DEPLOYMENT

This blog will talk about the environment variables ENABLE_ORYX_BUILD vs. SCM_DO_BUILD_DURING_DEPLOYMENT on App Service Linux and deployments.

Overview

These environment variables can be added to App Service Linux “Blessed Images” with the Node, Python, PHP and Dotnet options - this does not apply to Java “Blessed” images. Oryx is the builder used to do logical building of application content and dependencies (think builders and buildpacks), which deploys the source code and its dependencies onto /home/site/wwwroot. Information on specific builder logic per language can be found at Oryx - runtimes

NOTE: Ruby doesn’t apply since this has been long deprecated as an offering on App Service Linux

As shown here, the description is to avoid using the “legacy” builder system. However by this point in time, build systems should not be using any “legacy” builders when SCM_DO_BUILD_DURING_DEPLOYMENT is true aside from Oryx itself.

At times, users may use both environment variables. The TLDR is the following:

• Only worry about using SCM_DO_BUILD_DURING_DEPLOYMENT if you want build automation. If this is true, it’ll use Oryx to build your applications source and dependencies as explained above. Do not worry about adding ENABLE_ORYX_BUILD = true
• If SCM_DO_BUILD_DURING_DEPLOYMENT is false, Oryx will not be used. Therefor no build automation will be done - and if so, you need to deploy all your site contents (including all required application dependencies/packages/etc.) since no build automation is done

Matrix

SCM_DO_BUILD_DURING_DEPLOYMENT	ENABLE_ORYX_BUILD	Language	Will Oryx run?
true	true	Node	Yes
true	false	Node	No (through testing this is the one difference spotted between languages)
false	true	Node	No
false	false	Node	No

SCM_DO_BUILD_DURING_DEPLOYMENT	ENABLE_ORYX_BUILD	Language	Will Oryx run?
true	true	Python	Yes
true	false	Python	Yes
false	true	Python	No
false	false	Python	No

SCM_DO_BUILD_DURING_DEPLOYMENT	ENABLE_ORYX_BUILD	Language	Will Oryx run?
true	true	PHP	Yes
true	false	PHP	Yes
false	true	PHP	No
false	false	PHP	No

SCM_DO_BUILD_DURING_DEPLOYMENT	ENABLE_ORYX_BUILD	Language	Will Oryx run?
true	true	Dotnet	Yes
true	false	Dotnet	Yes
false	true	Dotnet	No
false	false	Dotnet	No