Very basic golang docker with new user.

* Expects go get/go mod to be used to handle application dependencies
* Expects users to use a volume mount to make code visible to the
  container
* Add a user (with the option of having the same UID/GID as current
  user) to avoid weird file owners when building things in the container
  as golang usually runs as root

docker/Dockerfile

@@ -0,0 +1,14 @@
+FROM golang:1.18
+
+ARG uid=1000
+ARG gid=1000
+
+# Dockerfile with static deps that won't be changed. Right now there's no deps
+# outside of what the go.mod file has to manage. Makes a user in the container
+# with the same UID and GID as the current user so that the mounted directory
+# doesn't end up with files with strange permissions.
+
+RUN groupadd -g "${gid}" build && \
+    useradd -m -u "${uid}" -g "${gid}" build
+
+USER build:build