add notes about CI, releases, usage

README.md

@@ -53,3 +53,54 @@ $ ./script/update -t arm64
 $ ./script/build -t arm64
 $ ./script/create-dist -t arm64
 ```
+
+## Releases
+
+There is no formal release process for libchromiumcontent, as release artifacts
+are created as a byproduct of CI. When a build is successful, its compiled
+asset is automatically uploaded to S3. These assets are later downloaded as 
+part of Electron's bootstrap script.  These files are about 4GB, so the 
+bootstrap task takes a while to run.
+
+Asset URLs have the following format:
+
+```js
+`https://s3.amazonaws.com/github-janky-artifacts/libchromiumcontent/${platform}/${commit}/libchromiumcontent.zip`
+```
+
+Builds exist for the following platform/arch pairs:
+
+- `osx/x64`
+- `mas/x64`
+- `win/ia32`
+- `win/x64`
+- `linux/ia32`
+- `linux/x64`
+- `linux/ar`
+
+The Linux machines only build for pushes by GitHub employees, so PRs 
+from third parties have to have their linux builds triggered manually.
+
+Each platform/arch has its own CI task, so it should be made sure that all 
+platform/arch have the CI tasks started and finished. To verify that
+a given commit has all the necessary build artifacts:
+
+```
+npm i -g electron/libcc-check
+libcc-check 7a9d4a1c9c265468dd54005f6c1920b2cc2c8ec3
+```
+
+## Setting libchromiumcontent version in Electron
+
+For Electron versions 1.7 and higher, libchromiumcontent is vendored as a git 
+submodule in the Electron repo. To change the version that Electron is using,
+use git to check out the target branch / SHA:
+
+```
+cd electron/electron/vendor/libchromiumcontent
+git checkout some-branch-or-sha
+```
+
+For Electron versions 1.6 and lower, libchromiumcontent is vendored as part
+of a (now retired) project called brightray. To change the version that 
+Electron is using, change the commit SHA in [config.py](https://github.com/electron/electron/blob/0428632a4e5dfa65e7ffbe39ff208069f0b9cdc4/script/lib/config.py#L12).