My patches for Rattlesnake OS.

Note that building opengapps with Rattlesnake OS will require a larger EC2 volume size. By default it's set to 200 GB, but can be increased by editing the value of the VolumeSize key in templates/lambda_template.go. 400 worked for me.

As well, opengapps' aosp_build requires zlib I created a script to install it, available at https://github.com/corrmaan/rattlesnakeos-scripts. git-lfs is also required but I didn't have luck with having it installed through the script, so I made a rattlesnakeos-stack patch for it, available here. After cloning rattlesnakeos-stack, apply the patch and build from source:

git clone https://github.com/dan-v/rattlesnakeos-stack.git
cd rattlesnakeos-stack
git checkout 794d5887d8e05ddcffb2d061204bd726c123e52e # 10.0.6
cd -
patch -p1<rattlesnakeos-stack-10.0.6-opengapps.patch
cd rattlesnakeos-stack
make tools && make

I have only tested this on my Pixel 2 (walleye), hence the specific patch for this device. PRs are welcome for other supported devices and/or a more generic patch.

Remember to add the following to your ~/.rattlesnakeos.toml config file, following the instructions for the OpenGApps AOSP based build system (https://github.com/opengapps/aosp_build):

[[custom-patches]]
  repo = "https://github.com/corrmaan/rattlesnakeos-patches"
  patches = [
      "00001-opengapps-find-apk-for-pkg.patch",
      "00002-opengapps-walleye.patch",
      "00003-magisk_mkbootfs.patch",
      "00004-enable-volte.patch",
  ]
  
[[custom-manifest-remotes]]
  name = "opengapps"
  fetch = "https://github.com/opengapps/"
  revision = "master"

[[custom-manifest-remotes]]
  name = "gitlab"
  fetch = "https://gitlab.opengapps.org/opengapps/"
  revision = "master"

[[custom-manifest-projects]]
  path = "vendor/opengapps/build"
  name = "aosp_build"
  remote = "opengapps"

[[custom-manifest-projects]]
  path = "vendor/opengapps/sources/all"
  name = "all"
  remote = "gitlab"

[[custom-manifest-projects]]
  path = "vendor/opengapps/sources/arm"
  name = "arm"
  remote = "gitlab"

[[custom-manifest-projects]]
  path = "vendor/opengapps/sources/arm64"
  name = "arm64"
  remote = "gitlab"

[[custom-manifest-projects]]
  path = "vendor/opengapps/sources/x86"
  name = "x86"
  remote = "gitlab"

[[custom-manifest-projects]]
  path = "vendor/opengapps/sources/x86_64"
  name = "x86_64"
  remote = "gitlab"

Please see CaseyBakey's work on including Magisk in the build. The add_magisk() function in their build script at https://github.com/CaseyBakey/chaosp/blob/master/build.sh should be added to templates/build_template.go and called after build_aosp and before release "${DEVICE}" in full_run().

This is implemented in a patch for rattlesnakeos-stack available here. After cloning rattlesnakeos-stack, apply the patch along with the above opengapps patch and build from source:

git clone https://github.com/dan-v/rattlesnakeos-stack.git
cd rattlesnakeos-stack
git checkout 794d5887d8e05ddcffb2d061204bd726c123e52e # 10.0.6
cd -
patch -p1<rattlesnakeos-stack-10.0.6-opengapps.patch # Optional
patch -p1<rattlesnakeos-stack-10.0.6-magisk.patch
cd rattlesnakeos-stack
make tools && make

Note that if Magisk is built in to RattlesnakeOS using this method it can only be applied as an OTA update. Your device will not boot if a factory image with Magisk is installed. So you'll need to first build RattlesnakeOS without Magisk (but opengapps can be included), flash that factory image, then build RattlesnakeOS with Magisk (and opengapps as well if it was built in to the factory image) and apply the new OTA manually or let your device update automatically over the internet.