From 2ae3f80b95130e302ee39691dfb6848955d32864 Mon Sep 17 00:00:00 2001
From: Jerry <jerrymarino@pinterest.com>
Date: Thu, 13 Feb 2020 13:34:09 -0800
Subject: [PATCH] Add documentation around manual code signing

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 Xcode/BuildSystemIntegration.md | 43 +++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 Xcode/BuildSystemIntegration.md

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+## Build system integration
+
+In Xcode, there are 2 build systems: Legacy and XCBuild.
+
+As of Xcode 11, XCBuild is the default build system selected by Xcode. As these
+build systems have quite different implementations and integration points, the
+document should discuss both.
+
+
+## XCBuild architecture
+
+XCBuild runs a build system daemon as a child process inside of Xcode. Xcode and
+the build service communicate via MessagePack protocol.
+[XCBuildKit](https://github.com/jerrymarino/xcbuildkit) aims to provide a way to
+integrate with XCBuild, and add features like the progress bar.
+
+
+## XCBuild manual code signing
+
+By default, XCBuild requires code signing.
+
+Prior to building, it emits the following error:
+
+```
+An empty identity is not valid when signing a binary for the product type 'Application'.
+```
+
+Set the following setting to disable code signing errors and manually sign:
+```
+CODE_SIGNING_ALLOWED = NO
+CODE_SIGN_STYLE = manual
+```
+
+
+## Legacy manual build code signing
+
+In legacy build, to disable code signing requires overriding 2 settings:
+
+```
+CODE_SIGNING_REQUIRED = NO
+CODE_SIGN_STYLE = manual
+```
+