diff --git a/Gemfile b/Gemfile
index 52ad3538..a94359cb 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,7 +2,7 @@ source "https://rubygems.org"
 
 ruby file: ".ruby-version"
 
-gem "rails", github: "rails/rails"
+gem "rails", github: "rails/rails", ref: "f32d09e2e8228c720a49c368de578559e37d7731"
 
 # Drivers
 gem "sqlite3", "~> 2.5"
diff --git a/Gemfile.lock b/Gemfile.lock
index a0cae4e8..fd6e412f 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -6,31 +6,32 @@ GIT
 
 GIT
   remote: https://github.com/rails/rails.git
-  revision: 13d5f87208921cc5139cd53b280c42f23c334826
+  revision: f32d09e2e8228c720a49c368de578559e37d7731
+  ref: f32d09e2e8228c720a49c368de578559e37d7731
   specs:
-    actioncable (8.0.0.beta1)
-      actionpack (= 8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    actioncable (8.1.0.alpha)
+      actionpack (= 8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       nio4r (~> 2.0)
       websocket-driver (>= 0.6.1)
       zeitwerk (~> 2.6)
-    actionmailbox (8.0.0.beta1)
-      actionpack (= 8.0.0.beta1)
-      activejob (= 8.0.0.beta1)
-      activerecord (= 8.0.0.beta1)
-      activestorage (= 8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    actionmailbox (8.1.0.alpha)
+      actionpack (= 8.1.0.alpha)
+      activejob (= 8.1.0.alpha)
+      activerecord (= 8.1.0.alpha)
+      activestorage (= 8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       mail (>= 2.8.0)
-    actionmailer (8.0.0.beta1)
-      actionpack (= 8.0.0.beta1)
-      actionview (= 8.0.0.beta1)
-      activejob (= 8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    actionmailer (8.1.0.alpha)
+      actionpack (= 8.1.0.alpha)
+      actionview (= 8.1.0.alpha)
+      activejob (= 8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       mail (>= 2.8.0)
       rails-dom-testing (~> 2.2)
-    actionpack (8.0.0.beta1)
-      actionview (= 8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    actionpack (8.1.0.alpha)
+      actionview (= 8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       nokogiri (>= 1.8.5)
       rack (>= 2.2.4)
       rack-session (>= 1.0.1)
@@ -38,35 +39,36 @@ GIT
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
       useragent (~> 0.16)
-    actiontext (8.0.0.beta1)
-      actionpack (= 8.0.0.beta1)
-      activerecord (= 8.0.0.beta1)
-      activestorage (= 8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    actiontext (8.1.0.alpha)
+      action_text-trix (~> 2.1.15)
+      actionpack (= 8.1.0.alpha)
+      activerecord (= 8.1.0.alpha)
+      activestorage (= 8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       globalid (>= 0.6.0)
       nokogiri (>= 1.8.5)
-    actionview (8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    actionview (8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       builder (~> 3.1)
       erubi (~> 1.11)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
-    activejob (8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    activejob (8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       globalid (>= 0.3.6)
-    activemodel (8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
-    activerecord (8.0.0.beta1)
-      activemodel (= 8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    activemodel (8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
+    activerecord (8.1.0.alpha)
+      activemodel (= 8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       timeout (>= 0.4.0)
-    activestorage (8.0.0.beta1)
-      actionpack (= 8.0.0.beta1)
-      activejob (= 8.0.0.beta1)
-      activerecord (= 8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    activestorage (8.1.0.alpha)
+      actionpack (= 8.1.0.alpha)
+      activejob (= 8.1.0.alpha)
+      activerecord (= 8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       marcel (~> 1.0)
-    activesupport (8.0.0.beta1)
+    activesupport (8.1.0.alpha)
       base64
       benchmark (>= 0.3)
       bigdecimal
@@ -79,41 +81,44 @@ GIT
       securerandom (>= 0.3)
       tzinfo (~> 2.0, >= 2.0.5)
       uri (>= 0.13.1)
-    rails (8.0.0.beta1)
-      actioncable (= 8.0.0.beta1)
-      actionmailbox (= 8.0.0.beta1)
-      actionmailer (= 8.0.0.beta1)
-      actionpack (= 8.0.0.beta1)
-      actiontext (= 8.0.0.beta1)
-      actionview (= 8.0.0.beta1)
-      activejob (= 8.0.0.beta1)
-      activemodel (= 8.0.0.beta1)
-      activerecord (= 8.0.0.beta1)
-      activestorage (= 8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+    rails (8.1.0.alpha)
+      actioncable (= 8.1.0.alpha)
+      actionmailbox (= 8.1.0.alpha)
+      actionmailer (= 8.1.0.alpha)
+      actionpack (= 8.1.0.alpha)
+      actiontext (= 8.1.0.alpha)
+      actionview (= 8.1.0.alpha)
+      activejob (= 8.1.0.alpha)
+      activemodel (= 8.1.0.alpha)
+      activerecord (= 8.1.0.alpha)
+      activestorage (= 8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       bundler (>= 1.15.0)
-      railties (= 8.0.0.beta1)
-    railties (8.0.0.beta1)
-      actionpack (= 8.0.0.beta1)
-      activesupport (= 8.0.0.beta1)
+      railties (= 8.1.0.alpha)
+    railties (8.1.0.alpha)
+      actionpack (= 8.1.0.alpha)
+      activesupport (= 8.1.0.alpha)
       irb (~> 1.13)
       rackup (>= 1.0.0)
       rake (>= 12.2)
       thor (~> 1.0, >= 1.2.2)
+      tsort (>= 0.2)
       zeitwerk (~> 2.6)
 
 GEM
   remote: https://rubygems.org/
   specs:
-    addressable (2.8.6)
-      public_suffix (>= 2.0.2, < 6.0)
-    ast (2.4.2)
-    base64 (0.2.0)
+    action_text-trix (2.1.15)
+      railties
+    addressable (2.8.7)
+      public_suffix (>= 2.0.2, < 7.0)
+    ast (2.4.3)
+    base64 (0.3.0)
     bcrypt (3.1.20)
-    benchmark (0.3.0)
-    bigdecimal (3.1.8)
+    benchmark (0.4.1)
+    bigdecimal (3.2.2)
     bindex (0.8.1)
-    brakeman (7.0.2)
+    brakeman (7.1.0)
       racc
     builder (3.3.0)
     capybara (3.40.0)
@@ -126,47 +131,49 @@ GEM
       regexp_parser (>= 1.5, < 3.0)
       xpath (~> 3.2)
     chunky_png (1.4.0)
-    concurrent-ruby (1.3.4)
-    connection_pool (2.4.1)
+    concurrent-ruby (1.3.5)
+    connection_pool (2.5.3)
     crass (1.0.6)
     date (3.4.1)
-    debug (1.10.0)
+    debug (1.11.0)
       irb (~> 1.10)
       reline (>= 0.3.8)
-    drb (2.2.1)
-    erubi (1.13.0)
-    faker (3.5.1)
+    drb (2.2.3)
+    erb (5.0.2)
+    erubi (1.13.1)
+    faker (3.5.2)
       i18n (>= 1.8.11, < 2)
-    ffi (1.17.0-aarch64-linux-gnu)
-    ffi (1.17.0-arm-linux-gnu)
-    ffi (1.17.0-arm64-darwin)
-    ffi (1.17.0-x86-linux-gnu)
-    ffi (1.17.0-x86_64-darwin)
-    ffi (1.17.0-x86_64-linux-gnu)
+    ffi (1.17.2-aarch64-linux-gnu)
+    ffi (1.17.2-arm-linux-gnu)
+    ffi (1.17.2-arm64-darwin)
+    ffi (1.17.2-x86-linux-gnu)
+    ffi (1.17.2-x86_64-darwin)
+    ffi (1.17.2-x86_64-linux-gnu)
     front_matter_parser (1.0.1)
     globalid (1.2.1)
       activesupport (>= 6.1)
-    i18n (1.14.6)
+    i18n (1.14.7)
       concurrent-ruby (~> 1.0)
-    image_processing (1.13.0)
-      mini_magick (>= 4.9.5, < 5)
+    image_processing (1.14.0)
+      mini_magick (>= 4.9.5, < 6)
       ruby-vips (>= 2.0.17, < 3)
-    importmap-rails (2.0.1)
+    importmap-rails (2.2.2)
       actionpack (>= 6.0.0)
       activesupport (>= 6.0.0)
       railties (>= 6.0.0)
-    io-console (0.8.0)
-    irb (1.15.1)
+    io-console (0.8.1)
+    irb (1.15.2)
       pp (>= 0.6.0)
       rdoc (>= 4.0.0)
       reline (>= 0.4.2)
-    jbuilder (2.13.0)
-      actionview (>= 5.0.0)
-      activesupport (>= 5.0.0)
-    json (2.7.2)
-    language_server-protocol (3.17.0.3)
-    logger (1.6.5)
-    loofah (2.23.1)
+    jbuilder (2.14.1)
+      actionview (>= 7.0.0)
+      activesupport (>= 7.0.0)
+    json (2.13.2)
+    language_server-protocol (3.17.0.5)
+    lint_roller (1.1.0)
+    logger (1.7.0)
+    loofah (2.24.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.12.0)
     mail (2.8.1)
@@ -175,89 +182,91 @@ GEM
       net-pop
       net-smtp
     marcel (1.0.4)
-    matrix (0.4.2)
-    mini_magick (4.13.2)
+    matrix (0.4.3)
+    mini_magick (5.3.0)
+      logger
     mini_mime (1.1.5)
-    mini_portile2 (2.8.8)
-    minitest (5.25.1)
+    mini_portile2 (2.8.9)
+    minitest (5.25.5)
     mono_logger (1.1.2)
-    multi_json (1.15.0)
-    mustermann (3.0.3)
+    multi_json (1.17.0)
+    mustermann (3.0.4)
       ruby2_keywords (~> 0.0.1)
-    net-imap (0.4.19)
+    net-imap (0.5.9)
       date
       net-protocol
     net-pop (0.1.2)
       net-protocol
     net-protocol (0.2.2)
       timeout
-    net-smtp (0.5.0)
+    net-smtp (0.5.1)
       net-protocol
     nio4r (2.7.4)
-    nokogiri (1.18.8)
+    nokogiri (1.18.9)
       mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
-    nokogiri (1.18.8-aarch64-linux-gnu)
+    nokogiri (1.18.9-aarch64-linux-gnu)
       racc (~> 1.4)
-    nokogiri (1.18.8-arm-linux-gnu)
+    nokogiri (1.18.9-arm-linux-gnu)
       racc (~> 1.4)
-    nokogiri (1.18.8-arm64-darwin)
+    nokogiri (1.18.9-arm64-darwin)
       racc (~> 1.4)
-    nokogiri (1.18.8-x86_64-darwin)
+    nokogiri (1.18.9-x86_64-darwin)
       racc (~> 1.4)
-    nokogiri (1.18.8-x86_64-linux-gnu)
+    nokogiri (1.18.9-x86_64-linux-gnu)
       racc (~> 1.4)
-    parallel (1.25.1)
-    parser (3.3.3.0)
+    parallel (1.27.0)
+    parser (3.3.9.0)
       ast (~> 2.4.1)
       racc
     pp (0.6.2)
       prettyprint
     prettyprint (0.2.0)
-    propshaft (1.0.0)
+    prism (1.4.0)
+    propshaft (1.2.1)
       actionpack (>= 7.0.0)
       activesupport (>= 7.0.0)
       rack
-      railties (>= 7.0.0)
-    psych (5.2.3)
+    psych (5.2.6)
       date
       stringio
-    public_suffix (5.0.5)
-    puma (6.6.0)
+    public_suffix (6.0.2)
+    puma (6.6.1)
       nio4r (~> 2.0)
     racc (1.8.1)
-    rack (3.1.11)
-    rack-protection (4.1.0)
+    rack (3.2.0)
+    rack-protection (4.1.1)
       base64 (>= 0.1.0)
       logger (>= 1.6.0)
       rack (>= 3.0.0, < 4)
-    rack-session (2.0.0)
+    rack-session (2.1.1)
+      base64 (>= 0.1.0)
       rack (>= 3.0.0)
-    rack-test (2.1.0)
+    rack-test (2.2.0)
       rack (>= 1.3)
-    rackup (2.1.0)
+    rackup (2.2.1)
       rack (>= 3)
-      webrick (~> 1.8)
-    rails-dom-testing (2.2.0)
+    rails-dom-testing (2.3.0)
       activesupport (>= 5.0.0)
       minitest
       nokogiri (>= 1.6)
-    rails-html-sanitizer (1.6.1)
+    rails-html-sanitizer (1.6.2)
       loofah (~> 2.21)
       nokogiri (>= 1.15.7, != 1.16.7, != 1.16.6, != 1.16.5, != 1.16.4, != 1.16.3, != 1.16.2, != 1.16.1, != 1.16.0.rc1, != 1.16.0)
     rainbow (3.1.1)
-    rake (13.2.1)
-    rdoc (6.11.0)
+    rake (13.3.0)
+    rdoc (6.14.2)
+      erb
       psych (>= 4.0.0)
-    redcarpet (3.6.0)
-    redis (5.3.0)
+    redcarpet (3.6.1)
+    redis (5.4.1)
       redis-client (>= 0.22.0)
-    redis-client (0.22.2)
+    redis-client (0.25.2)
       connection_pool
     redis-namespace (1.11.0)
       redis (>= 4)
-    regexp_parser (2.9.2)
-    reline (0.6.0)
+    regexp_parser (2.11.2)
+    reline (0.6.2)
       io-console (~> 0.5)
     resque (2.6.0)
       mono_logger (~> 1.0)
@@ -267,98 +276,100 @@ GEM
     resque-pool (0.7.1)
       rake (>= 10.0, < 14.0)
       resque (>= 1.22, < 3)
-    rexml (3.4.0)
-    rouge (4.5.1)
-    rqrcode (2.2.0)
+    rexml (3.4.1)
+    rouge (4.6.0)
+    rqrcode (3.1.0)
       chunky_png (~> 1.0)
-      rqrcode_core (~> 1.0)
-    rqrcode_core (1.2.0)
-    rubocop (1.64.1)
+      rqrcode_core (~> 2.0)
+    rqrcode_core (2.0.0)
+    rubocop (1.79.2)
       json (~> 2.3)
-      language_server-protocol (>= 3.17.0)
+      language_server-protocol (~> 3.17.0.2)
+      lint_roller (~> 1.1.0)
       parallel (~> 1.10)
       parser (>= 3.3.0.2)
       rainbow (>= 2.2.2, < 4.0)
-      regexp_parser (>= 1.8, < 3.0)
-      rexml (>= 3.2.5, < 4.0)
-      rubocop-ast (>= 1.31.1, < 2.0)
+      regexp_parser (>= 2.9.3, < 3.0)
+      rubocop-ast (>= 1.46.0, < 2.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 2.4.0, < 3.0)
-    rubocop-ast (1.31.3)
-      parser (>= 3.3.1.0)
-    rubocop-minitest (0.35.0)
-      rubocop (>= 1.61, < 2.0)
-      rubocop-ast (>= 1.31.1, < 2.0)
-    rubocop-performance (1.21.0)
-      rubocop (>= 1.48.1, < 2.0)
-      rubocop-ast (>= 1.31.1, < 2.0)
-    rubocop-rails (2.25.0)
+      unicode-display_width (>= 2.4.0, < 4.0)
+    rubocop-ast (1.46.0)
+      parser (>= 3.3.7.2)
+      prism (~> 1.4)
+    rubocop-performance (1.25.0)
+      lint_roller (~> 1.1)
+      rubocop (>= 1.75.0, < 2.0)
+      rubocop-ast (>= 1.38.0, < 2.0)
+    rubocop-rails (2.33.3)
       activesupport (>= 4.2.0)
+      lint_roller (~> 1.1)
       rack (>= 1.1)
-      rubocop (>= 1.33.0, < 2.0)
-      rubocop-ast (>= 1.31.1, < 2.0)
-    rubocop-rails-omakase (1.0.0)
-      rubocop
-      rubocop-minitest
-      rubocop-performance
-      rubocop-rails
+      rubocop (>= 1.75.0, < 2.0)
+      rubocop-ast (>= 1.44.0, < 2.0)
+    rubocop-rails-omakase (1.1.0)
+      rubocop (>= 1.72)
+      rubocop-performance (>= 1.24)
+      rubocop-rails (>= 2.30)
     ruby-progressbar (1.13.0)
-    ruby-vips (2.2.2)
+    ruby-vips (2.2.4)
       ffi (~> 1.12)
       logger
     ruby2_keywords (0.0.5)
-    rubyzip (2.4.1)
-    securerandom (0.3.1)
-    selenium-webdriver (4.28.0)
+    rubyzip (3.0.1)
+    securerandom (0.4.1)
+    selenium-webdriver (4.35.0)
       base64 (~> 0.2)
       logger (~> 1.4)
       rexml (~> 3.2, >= 3.2.5)
-      rubyzip (>= 1.2.2, < 3.0)
+      rubyzip (>= 1.2.2, < 4.0)
       websocket (~> 1.0)
-    sinatra (4.1.0)
+    sinatra (4.1.1)
       logger (>= 1.6.0)
       mustermann (~> 3.0)
       rack (>= 3.0.0, < 4)
-      rack-protection (= 4.1.0)
+      rack-protection (= 4.1.1)
       rack-session (>= 2.0.0, < 3)
       tilt (~> 2.0)
-    sqlite3 (2.5.0-aarch64-linux-gnu)
-    sqlite3 (2.5.0-arm-linux-gnu)
-    sqlite3 (2.5.0-arm64-darwin)
-    sqlite3 (2.5.0-x86-linux-gnu)
-    sqlite3 (2.5.0-x86_64-darwin)
-    sqlite3 (2.5.0-x86_64-linux-gnu)
+    sqlite3 (2.7.3-aarch64-linux-gnu)
+    sqlite3 (2.7.3-arm-linux-gnu)
+    sqlite3 (2.7.3-arm64-darwin)
+    sqlite3 (2.7.3-x86-linux-gnu)
+    sqlite3 (2.7.3-x86_64-darwin)
+    sqlite3 (2.7.3-x86_64-linux-gnu)
     stimulus-rails (1.3.4)
       railties (>= 6.0.0)
-    stringio (3.1.2)
-    thor (1.3.2)
-    thruster (0.1.9)
-    thruster (0.1.9-aarch64-linux)
-    thruster (0.1.9-arm64-darwin)
-    thruster (0.1.9-x86_64-darwin)
-    thruster (0.1.9-x86_64-linux)
-    tilt (2.4.0)
+    stringio (3.1.7)
+    thor (1.4.0)
+    thruster (0.1.15)
+    thruster (0.1.15-aarch64-linux)
+    thruster (0.1.15-arm64-darwin)
+    thruster (0.1.15-x86_64-darwin)
+    thruster (0.1.15-x86_64-linux)
+    tilt (2.6.1)
     timeout (0.4.3)
-    turbo-rails (2.0.11)
-      actionpack (>= 6.0.0)
-      railties (>= 6.0.0)
+    tsort (0.2.0)
+    turbo-rails (2.0.16)
+      actionpack (>= 7.1.0)
+      railties (>= 7.1.0)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
-    unicode-display_width (2.5.0)
-    uri (0.13.2)
+    unicode-display_width (3.1.5)
+      unicode-emoji (~> 4.0, >= 4.0.4)
+    unicode-emoji (4.0.4)
+    uri (1.0.3)
     web-console (4.2.1)
       actionview (>= 6.0.0)
       activemodel (>= 6.0.0)
       bindex (>= 0.4.0)
       railties (>= 6.0.0)
-    webrick (1.8.2)
     websocket (1.2.11)
-    websocket-driver (0.7.6)
+    websocket-driver (0.8.0)
+      base64
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.5)
     xpath (3.2.0)
       nokogiri (~> 1.8)
-    zeitwerk (2.7.1)
+    zeitwerk (2.7.3)
 
 PLATFORMS
   aarch64-linux
diff --git a/app/controllers/leafables_controller.rb b/app/controllers/leafables_controller.rb
index bf472599..c2a300a4 100644
--- a/app/controllers/leafables_controller.rb
+++ b/app/controllers/leafables_controller.rb
@@ -16,6 +16,10 @@ def create
   end
 
   def show
+    respond_to do |format|
+      format.html
+      format.md { render markdown: @leaf.leafable }
+    end
   end
 
   def edit
diff --git a/app/models/book.rb b/app/models/book.rb
index 93de9985..234461d3 100644
--- a/app/models/book.rb
+++ b/app/models/book.rb
@@ -12,4 +12,10 @@ class Book < ApplicationRecord
   def press(leafable, leaf_params)
     leaves.create! leaf_params.merge(leafable: leafable)
   end
+
+  def to_markdown
+    leaves.active.with_leafables.positioned \
+      .collect { |leaf| leaf.leafable.to_markdown }
+      .join("\n\n")
+  end
 end
diff --git a/app/models/leafable.rb b/app/models/leafable.rb
index 6d90efd5..0e6185dc 100644
--- a/app/models/leafable.rb
+++ b/app/models/leafable.rb
@@ -11,7 +11,9 @@ module Leafable
   end
 
   def searchable_content
-    nil
+  end
+
+  def to_markdown
   end
 
   class_methods do
diff --git a/app/models/page.rb b/app/models/page.rb
index 5b4adba8..3585bdeb 100644
--- a/app/models/page.rb
+++ b/app/models/page.rb
@@ -16,6 +16,10 @@ def html_preview
     rendered_html(markdown_source.first(1024))
   end
 
+  def to_markdown
+    body.content
+  end
+
   private
     def plain_text
       html_body = rendered_html(markdown_source)
diff --git a/app/models/picture.rb b/app/models/picture.rb
index 1a2acde7..043b9afe 100644
--- a/app/models/picture.rb
+++ b/app/models/picture.rb
@@ -4,4 +4,8 @@ class Picture < ApplicationRecord
   has_one_attached :image do |attachable|
     attachable.variant :large, resize_to_limit: [ 1500, 1500 ]
   end
+
+  def to_markdown
+    "#{caption.presence || image&.attachment&.slug || "Image"}"
+  end
 end
diff --git a/app/models/section.rb b/app/models/section.rb
index f86f7046..a6fe574b 100644
--- a/app/models/section.rb
+++ b/app/models/section.rb
@@ -4,4 +4,8 @@ class Section < ApplicationRecord
   def searchable_content
     body
   end
+
+  def to_markdown
+    "# #{body}"
+  end
 end
diff --git a/test/controllers/leafables_controller_test.rb b/test/controllers/leafables_controller_test.rb
index 9fa0c8ff..24d8d14f 100644
--- a/test/controllers/leafables_controller_test.rb
+++ b/test/controllers/leafables_controller_test.rb
@@ -12,6 +12,13 @@ class LeafablesControllerTest < ActionDispatch::IntegrationTest
     assert_select "p", "This is such a great handbook."
   end
 
+  test "show markdown" do
+    get leafable_slug_path(leaves(:welcome_page), format: "md")
+
+    assert_response :success
+    assert_equal "This is _such_ a great handbook.", @response.body
+  end
+
   test "show with public access to a published book" do
     sign_out
     books(:handbook).update!(published: true)