diff --git a/.erdconfig b/.erdconfig
new file mode 100644
index 0000000..8f3f359
--- /dev/null
+++ b/.erdconfig
@@ -0,0 +1,3 @@
+title: Progress Test - Models
+filetype: svg
+warn: false
diff --git a/Gemfile b/Gemfile
index 6f5d015..a42bb24 100644
--- a/Gemfile
+++ b/Gemfile
@@ -43,6 +43,7 @@ end
 
 group :development do
   gem "annotate", "~> 3.2"
+  gem "rails-erd", "~> 1.7"
 
   gem "web-console"
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index dc530b9..fba12c6 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -86,6 +86,7 @@ GEM
     bootsnap (1.12.0)
       msgpack (~> 1.2)
     builder (3.2.4)
+    choice (0.2.0)
     concurrent-ruby (1.1.10)
     crass (1.0.6)
     debug (1.6.1)
@@ -227,6 +228,11 @@ GEM
     rails-dom-testing (2.0.3)
       activesupport (>= 4.2.0)
       nokogiri (>= 1.6)
+    rails-erd (1.7.1)
+      activerecord (>= 4.2)
+      activesupport (>= 4.2)
+      choice (~> 0.2.0)
+      ruby-graphviz (~> 1.2)
     rails-html-sanitizer (1.4.3)
       loofah (~> 2.3)
     railties (7.0.3.1)
@@ -247,6 +253,7 @@ GEM
     responders (3.0.1)
       actionpack (>= 5.0)
       railties (>= 5.0)
+    rexml (3.2.5)
     rspec-core (3.11.0)
       rspec-support (~> 3.11.0)
     rspec-expectations (3.11.0)
@@ -264,6 +271,8 @@ GEM
       rspec-mocks (~> 3.10)
       rspec-support (~> 3.10)
     rspec-support (3.11.0)
+    ruby-graphviz (1.2.5)
+      rexml
     ruby2_keywords (0.0.5)
     sassc (2.4.0)
       ffi (~> 1.9)
@@ -322,6 +331,7 @@ DEPENDENCIES
   pg (~> 1.1)
   puma (~> 5.0)
   rails (~> 7.0.3, >= 7.0.3.1)
+  rails-erd (~> 1.7)
   redis (~> 4.0)
   rspec-rails (~> 5.1)
   sassc-rails
diff --git a/erd.svg b/erd.svg
new file mode 100644
index 0000000..1f5f115
--- /dev/null
+++ b/erd.svg
@@ -0,0 +1,52 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
+ "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<!-- Generated by graphviz version 4.0.0 (0)
+ -->
+<!-- Title: ProgressTest Pages: 1 -->
+<svg width="416pt" height="204pt"
+ viewBox="0.00 0.00 416.10 203.60" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
+<g id="graph0" class="graph" transform="scale(1 1) rotate(0) translate(28.8 174.8)">
+<title>ProgressTest</title>
+<polygon fill="white" stroke="transparent" points="-28.8,28.8 -28.8,-174.8 387.3,-174.8 387.3,28.8 -28.8,28.8"/>
+<text text-anchor="middle" x="179.25" y="-131.6" font-family="Arial Bold" font-size="13.00">Progress Test &#45; Models</text>
+<!-- m_ActiveAdmin::Comment -->
+<g id="node1" class="node">
+<title>m_ActiveAdmin::Comment</title>
+<path fill="none" stroke="black" d="M12,-0.5C12,-0.5 132,-0.5 132,-0.5 138,-0.5 144,-6.5 144,-12.5 144,-12.5 144,-96.5 144,-96.5 144,-102.5 138,-108.5 132,-108.5 132,-108.5 12,-108.5 12,-108.5 6,-108.5 0,-102.5 0,-96.5 0,-96.5 0,-12.5 0,-12.5 0,-6.5 6,-0.5 12,-0.5"/>
+<text text-anchor="start" x="6.5" y="-95.7" font-family="Arial Bold" font-size="11.00">ActiveAdmin::Comment</text>
+<polyline fill="none" stroke="black" points="0,-88.5 144,-88.5 "/>
+<text text-anchor="start" x="7" y="-75.5" font-family="Arial" font-size="10.00">author_id </text>
+<text text-anchor="start" x="50" y="-75.5" font-family="Arial Italic" font-size="10.00" fill="#999999">integer (8)</text>
+<text text-anchor="start" x="7" y="-62.5" font-family="Arial" font-size="10.00">author_type </text>
+<text text-anchor="start" x="62" y="-62.5" font-family="Arial Italic" font-size="10.00" fill="#999999">string</text>
+<text text-anchor="start" x="7" y="-49.5" font-family="Arial" font-size="10.00">body </text>
+<text text-anchor="start" x="32" y="-49.5" font-family="Arial Italic" font-size="10.00" fill="#999999">text ∗</text>
+<text text-anchor="start" x="7" y="-36.5" font-family="Arial" font-size="10.00">namespace </text>
+<text text-anchor="start" x="61" y="-36.5" font-family="Arial Italic" font-size="10.00" fill="#999999">string ∗</text>
+<text text-anchor="start" x="7" y="-23.5" font-family="Arial" font-size="10.00">resource_id </text>
+<text text-anchor="start" x="61" y="-23.5" font-family="Arial Italic" font-size="10.00" fill="#999999">integer (8)</text>
+<text text-anchor="start" x="7" y="-10.5" font-family="Arial" font-size="10.00">resource_type </text>
+<text text-anchor="start" x="72" y="-10.5" font-family="Arial Italic" font-size="10.00" fill="#999999">string</text>
+</g>
+<!-- m_User -->
+<g id="node2" class="node">
+<title>m_User</title>
+<path fill="none" stroke="black" d="M185.5,-0.5C185.5,-0.5 346.5,-0.5 346.5,-0.5 352.5,-0.5 358.5,-6.5 358.5,-12.5 358.5,-12.5 358.5,-96.5 358.5,-96.5 358.5,-102.5 352.5,-108.5 346.5,-108.5 346.5,-108.5 185.5,-108.5 185.5,-108.5 179.5,-108.5 173.5,-102.5 173.5,-96.5 173.5,-96.5 173.5,-12.5 173.5,-12.5 173.5,-6.5 179.5,-0.5 185.5,-0.5"/>
+<text text-anchor="start" x="251.5" y="-95.7" font-family="Arial Bold" font-size="11.00">User</text>
+<polyline fill="none" stroke="black" points="173.5,-88.5 358.5,-88.5 "/>
+<text text-anchor="start" x="181" y="-75.5" font-family="Arial" font-size="10.00">email </text>
+<text text-anchor="start" x="208" y="-75.5" font-family="Arial Italic" font-size="10.00" fill="#999999">string ∗ U</text>
+<text text-anchor="start" x="181" y="-62.5" font-family="Arial" font-size="10.00">encrypted_password </text>
+<text text-anchor="start" x="275" y="-62.5" font-family="Arial Italic" font-size="10.00" fill="#999999">string ∗</text>
+<text text-anchor="start" x="181" y="-49.5" font-family="Arial" font-size="10.00">name </text>
+<text text-anchor="start" x="209" y="-49.5" font-family="Arial Italic" font-size="10.00" fill="#999999">string ∗</text>
+<text text-anchor="start" x="181" y="-36.5" font-family="Arial" font-size="10.00">remember_created_at </text>
+<text text-anchor="start" x="279" y="-36.5" font-family="Arial Italic" font-size="10.00" fill="#999999">datetime (6,0)</text>
+<text text-anchor="start" x="181" y="-23.5" font-family="Arial" font-size="10.00">reset_password_sent_at </text>
+<text text-anchor="start" x="291" y="-23.5" font-family="Arial Italic" font-size="10.00" fill="#999999">datetime (6,0)</text>
+<text text-anchor="start" x="181" y="-10.5" font-family="Arial" font-size="10.00">reset_password_token </text>
+<text text-anchor="start" x="283" y="-10.5" font-family="Arial Italic" font-size="10.00" fill="#999999">string</text>
+</g>
+</g>
+</svg>