diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 000000000..a85b5fb6b
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1,36 @@
+# Version control
+.git
+.gitignore
+
+# Confidential information
+config/database.yml
+config/secrets.yml
+config/deploy-secrets.yml
+config/maintenance.yml
+
+# Logfiles and tempfiles.
+**/log/*
+!**/log/.keep
+**/tmp/
+
+# Files attached by users
+public/system/
+public/ckeditor_assets/
+storage/
+
+# Files generated by scripts or compiled
+public/sitemap.xml
+public/assets/
+public/machine_learning/data/
+
+# Bundler config, cache and gemsets
+**/.bundle/
+**/.ruby-gemset
+
+# Files used in local development
+**/.byebug_history
+**/.DS_Store
+
+# Test results
+spec/examples.txt
+coverage/
diff --git a/.gitignore b/.gitignore
index f973f1158..7e10963eb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,40 +4,35 @@
 # or operating system, you probably want to add a global ignore instead:
 #   git config --global core.excludesfile '~/.gitignore_global'
 
-# Ignore bundler config.
-/.bundle
-
-# Ignore the default SQLite database.
-/db/*.sqlite3
-/db/*.sqlite3-journal
-
-# Ignore all logfiles and tempfiles.
-/log/*
-!/log/.keep
-/tmp
-
-/spec/examples.txt
+# Confidential information
 /config/database.yml
 /config/secrets.yml
 /config/deploy-secrets.yml
 /config/maintenance.yml
 
-/coverage
+# Logfiles and tempfiles.
+log/*
+!log/.keep
+tmp/
 
-/config/beta-testers.txt
-.byebug_history
+# Files attached by users
+/public/system/
+/public/ckeditor_assets/
+/storage/
 
-# Mac finder artifacts
-.DS_Store
-
-# Intellij IDE project settings
-/.idea
+# Files generated by scripts or compiled
+/public/sitemap.xml
+/public/assets/
+/public/machine_learning/data/
 
+# Bundler config, cache and gemsets
+.bundle/
 .ruby-gemset
 
-public/sitemap.xml
-public/assets/
-public/machine_learning/data/
-public/system/
-/public/ckeditor_assets/
-storage/
+# Files used in local development
+.byebug_history
+.DS_Store
+
+# Test results
+/spec/examples.txt
+/coverage/