doc: document docker image build

Author: guggero

doc/compile.md

@@ -26,3 +26,44 @@ need to download those binaries from the
 [loop](https://github.com/lightninglabs/loop/releases),
 [pool](https://github.com/lightninglabs/pool/releases), and
 [faraday](https://github.com/lightninglabs/faraday/releases) repos manually.
+
+## Building a docker image
+
+There are two flavors of Dockerfiles available:
+ - `Dockerfile`: Used for production builds. Checks out the source code from
+   GitHub during build. The build argument `--build-arg checkout=v0.x.x-alpha`
+   can be used to specify what git tag or commit to check out before building.
+ - `dev.Dockerfile` Used for development or testing builds. Uses the local code
+   when building and allows local changes to be tested more easily.
+
+### Building a development docker image
+
+Follow the instructions of the [previous chapter](#compile-from-source-code) to
+install all necessary dependencies.
+
+Then, instead of `make install` run the following commands:
+
+```shell script
+$ docker build -f dev.Dockerfile -t my-lit-dev-image .
+```
+
+If successful, you can then run the docker image with:
+
+```shell script
+$ docker run -p 8443:8443 --rm --name litd my-lit-dev-image \
+  --httpslisten=0.0.0.0:8443 \
+  ... (your configuration flags here)
+```
+
+See the [execution section in the main README](../README.md#execution) to find
+out what configuration flags to use.
+
+### Building a production docker image
+
+To create a production build, you need to specify the git tag to create the
+image from. All local files will be ignored, everything is cloned and built from
+GitHub so you don't need to install any dependencies:
+
+```shell script
+$ docker build -t lightninglabs/lightning-terminal --build-arg checkout=v0.3.2-alpha .
+```