diff --git a/Gemfile.lock b/Gemfile.lock
index b29cf9d..27cd766 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -36,7 +36,7 @@ GIT
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (7.1.3.2)
+    activesupport (7.1.3.3)
       base64
       bigdecimal
       concurrent-ruby (~> 1.0, >= 1.0.2)
@@ -53,8 +53,10 @@ GEM
     ast (2.4.2)
     babosa (2.0.0)
     base64 (0.2.0)
-    bcrypt_pbkdf (1.1.0)
-    bigdecimal (3.1.7)
+    bcrypt_pbkdf (1.1.1)
+    bcrypt_pbkdf (1.1.1-arm64-darwin)
+    bcrypt_pbkdf (1.1.1-x86_64-darwin)
+    bigdecimal (3.1.8)
     bskyrb (0.5.3)
       date (>= 3.3.3)
       httparty (>= 0.21.0)
@@ -87,7 +89,7 @@ GEM
     date (3.3.4)
     diff-lcs (1.5.1)
     domain_name (0.6.20240107)
-    dotenv (3.1.0)
+    dotenv (3.1.2)
     down (5.4.2)
       addressable (~> 2.8)
     drb (2.2.1)
@@ -107,7 +109,7 @@ GEM
     dry-files (1.1.0)
     dry-inflector (1.0.0)
     dry-initializer (3.1.1)
-    dry-logger (1.0.3)
+    dry-logger (1.0.4)
     dry-logic (1.5.0)
       concurrent-ruby (~> 1.0)
       dry-core (~> 1.0, < 2)
@@ -122,7 +124,7 @@ GEM
       dry-configurable (~> 1.0, < 2)
       dry-core (~> 1.0, < 2)
       dry-events (~> 1.0, < 2)
-    dry-schema (1.13.3)
+    dry-schema (1.13.4)
       concurrent-ruby (~> 1.0)
       dry-configurable (~> 1.0, >= 1.0.1)
       dry-core (~> 1.0, < 2)
@@ -260,18 +262,19 @@ GEM
     http-accept (1.7.0)
     http-cookie (1.0.5)
       domain_name (~> 0.5)
-    httparty (0.21.0)
+    httparty (0.22.0)
+      csv
       mini_mime (>= 1.0.0)
       multi_xml (>= 0.5.2)
-    i18n (1.14.4)
+    i18n (1.14.5)
       concurrent-ruby (~> 1.0)
     ice_nine (0.11.2)
     image_processing (1.12.2)
       mini_magick (>= 4.9.5, < 5)
       ruby-vips (>= 2.0.17, < 3)
     io-console (0.7.2)
-    irb (1.12.0)
-      rdoc
+    irb (1.13.1)
+      rdoc (>= 4.0.0)
       reline (>= 0.4.2)
     json (2.7.2)
     jwt (2.8.1)
@@ -294,12 +297,13 @@ GEM
     method_source (1.1.0)
     mime-types (3.5.2)
       mime-types-data (~> 3.2015)
-    mime-types-data (3.2024.0305)
+    mime-types-data (3.2024.0507)
     mini_magick (4.12.0)
     mini_mime (1.1.5)
-    minitest (5.22.3)
-    multi_xml (0.6.0)
-    multipart-post (2.4.0)
+    minitest (5.23.1)
+    multi_xml (0.7.1)
+      bigdecimal (~> 3.1)
+    multipart-post (2.4.1)
     mustermann (3.0.0)
       ruby2_keywords (~> 0.0.1)
     mustermann-contrib (3.0.0)
@@ -307,7 +311,7 @@ GEM
       mustermann (= 3.0.0)
     mutex_m (0.2.0)
     nenv (0.3.0)
-    net-imap (0.4.10)
+    net-imap (0.4.11)
       date
       net-protocol
     net-pop (0.1.2)
@@ -322,12 +326,12 @@ GEM
       net-protocol
     net-ssh (7.2.3)
     netrc (0.11.0)
-    nio4r (2.7.1)
-    nokogiri (1.16.4-arm64-darwin)
+    nio4r (2.7.3)
+    nokogiri (1.16.5-arm64-darwin)
       racc (~> 1.4)
-    nokogiri (1.16.4-x86_64-darwin)
+    nokogiri (1.16.5-x86_64-darwin)
       racc (~> 1.4)
-    nokogiri (1.16.4-x86_64-linux)
+    nokogiri (1.16.5-x86_64-linux)
       racc (~> 1.4)
     notiffany (0.1.3)
       nenv (~> 0.1)
@@ -346,7 +350,7 @@ GEM
       activesupport
       httparty
     parallel (1.24.0)
-    parser (3.3.0.5)
+    parser (3.3.1.0)
       ast (~> 2.4.1)
       racc
     pg (1.5.6)
@@ -359,9 +363,9 @@ GEM
     puma (6.4.2)
       nio4r (~> 2.0)
     que (2.3.0)
-    racc (1.7.3)
+    racc (1.8.0)
     rack (2.2.9)
-    rack-contrib (2.4.0)
+    rack-contrib (2.5.0)
       rack (< 4)
     rack-rewrite (1.5.1)
     rack-session (1.0.2)
@@ -371,17 +375,17 @@ GEM
     rainbow (3.1.1)
     rake (13.2.1)
     rb-fsevent (0.11.2)
-    rb-inotify (0.10.1)
+    rb-inotify (0.11.1)
       ffi (~> 1.0)
-    rdoc (6.6.3.1)
+    rdoc (6.7.0)
       psych (>= 4.0.0)
     redcarpet (3.6.0)
     redis (5.2.0)
       redis-client (>= 0.22.0)
-    redis-client (0.22.1)
+    redis-client (0.22.2)
       connection_pool
-    regexp_parser (2.9.0)
-    reline (0.5.2)
+    regexp_parser (2.9.2)
+    reline (0.5.7)
       io-console (~> 0.5)
     rest-client (2.1.0)
       http-accept (>= 1.7.0, < 2.0)
@@ -390,16 +394,17 @@ GEM
       netrc (~> 0.8)
     reverse_markdown (2.1.1)
       nokogiri
-    rexml (3.2.6)
-    rom (5.3.0)
+    rexml (3.2.8)
+      strscan (>= 3.0.9)
+    rom (5.3.2)
       rom-changeset (~> 5.3, >= 5.3.0)
-      rom-core (~> 5.3, >= 5.3.0)
+      rom-core (~> 5.3, >= 5.3.2)
       rom-repository (~> 5.3, >= 5.3.0)
     rom-changeset (5.3.0)
       dry-core (~> 1.0)
       rom-core (~> 5.3)
       transproc (~> 1.0, >= 1.1.0)
-    rom-core (5.3.1)
+    rom-core (5.3.2)
       concurrent-ruby (~> 1.1)
       dry-configurable (~> 1.0)
       dry-core (~> 1.0)
@@ -418,7 +423,7 @@ GEM
       dry-core (~> 1.0)
       dry-initializer (~> 3.0, >= 3.0.1)
       rom-core (~> 5.3, >= 5.3.0)
-    rom-sql (3.6.2)
+    rom-sql (3.6.3)
       dry-core (~> 1.0)
       dry-types (~> 1.0)
       rom (~> 5.2, >= 5.2.1)
@@ -432,11 +437,11 @@ GEM
     rspec-expectations (3.13.0)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-mocks (3.13.0)
+    rspec-mocks (3.13.1)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
     rspec-support (3.13.1)
-    rubocop (1.62.1)
+    rubocop (1.63.5)
       json (~> 2.3)
       language_server-protocol (>= 3.17.0)
       parallel (~> 1.10)
@@ -447,11 +452,11 @@ GEM
       rubocop-ast (>= 1.31.1, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 2.4.0, < 3.0)
-    rubocop-ast (1.31.2)
-      parser (>= 3.3.0.4)
-    rubocop-performance (1.20.2)
+    rubocop-ast (1.31.3)
+      parser (>= 3.3.1.0)
+    rubocop-performance (1.21.0)
       rubocop (>= 1.48.1, < 2.0)
-      rubocop-ast (>= 1.30.0, < 2.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
     ruby-progressbar (1.13.0)
     ruby-readability (0.7.0)
       guess_html_encoding (>= 0.0.4)
@@ -462,7 +467,7 @@ GEM
     sanitize (6.1.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.12.0)
-    sequel (5.79.0)
+    sequel (5.80.0)
       bigdecimal
     shellany (0.0.1)
     simple-rss (1.3.3)
@@ -472,29 +477,30 @@ GEM
     snaky_hash (2.0.1)
       hashie
       version_gem (~> 1.1, >= 1.1.1)
-    sshkit (1.22.1)
+    sshkit (1.22.2)
       base64
       mutex_m
       net-scp (>= 1.1.2)
       net-sftp (>= 2.1.2)
       net-ssh (>= 2.8.0)
-    standard (1.35.1)
+    standard (1.36.0)
       language_server-protocol (~> 3.17.0.2)
       lint_roller (~> 1.0)
-      rubocop (~> 1.62.0)
+      rubocop (~> 1.63.0)
       standard-custom (~> 1.0.0)
-      standard-performance (~> 1.3)
+      standard-performance (~> 1.4)
     standard-custom (1.0.2)
       lint_roller (~> 1.0)
       rubocop (~> 1.50)
-    standard-performance (1.3.1)
+    standard-performance (1.4.0)
       lint_roller (~> 1.1)
-      rubocop-performance (~> 1.20.2)
+      rubocop-performance (~> 1.21.0)
     standardrb (1.0.1)
       standard
     steam-api (1.2.0)
       faraday (~> 1.0)
     stringio (3.1.0)
+    strscan (3.1.0)
     temple (0.10.3)
     thor (1.3.1)
     tilt (2.3.0)
@@ -508,9 +514,9 @@ GEM
     unicode-emoji (3.4.0)
       unicode-version (~> 1.0)
     unicode-version (1.4.0)
-    vernier (0.7.0)
+    vernier (1.0.1)
     version_gem (1.1.4)
-    warning (1.3.0)
+    warning (1.4.0)
     whenever (1.0.0)
       chronic (>= 0.6.3)
     xml-simple (1.1.9)
@@ -519,7 +525,7 @@ GEM
       date
       httparty
       json (>= 2.0)
-    zeitwerk (2.6.13)
+    zeitwerk (2.6.15)
 
 PLATFORMS
   arm64-darwin-23
diff --git a/slices/micropub/commands/posts/update.rb b/slices/micropub/commands/posts/update.rb
index 7ed6909..36e3b87 100644
--- a/slices/micropub/commands/posts/update.rb
+++ b/slices/micropub/commands/posts/update.rb
@@ -5,7 +5,8 @@ module Micropub
         include Deps[
           "repos.post_repo",
           "renderers.markdown",
-          "commands.posts.add_syndication_source"
+          "commands.posts.add_syndication_source",
+          "queries.posts.syndication_url_to_source"
         ]
 
         def call(params:)
@@ -31,7 +32,8 @@ module Micropub
           if params.key? :add
             attrs_to_add = {}
 
-            syndication = params[:add].delete(:syndication)&.first
+            syndication_url = params[:add].delete(:syndication)&.first
+            syndication_source = syndication_url_to_source.call(url: syndication_url) if syndication_url && !syndication_url.empty?
             tags = params[:add].delete(:category)
             content = params[:add].delete(:content)&.first
             name = params[:add].delete(:name)
@@ -46,7 +48,7 @@ module Micropub
             post_repo.update(post.id, attrs_to_add) unless attrs_to_add.empty?
 
             post_repo.tag_post(post_id: post.id, tags: tags) if tags && !tags.empty?
-            add_syndication_source.call(post.id, "", syndication) if syndication && !syndication.empty?
+            add_syndication_source.call(post.id, syndication_source, syndication_url) if syndication_url && !syndication_url.empty?
 
             Success()
           end
diff --git a/slices/micropub/queries/posts/syndication_url_to_source.rb b/slices/micropub/queries/posts/syndication_url_to_source.rb
new file mode 100644
index 0000000..cc8a6d4
--- /dev/null
+++ b/slices/micropub/queries/posts/syndication_url_to_source.rb
@@ -0,0 +1,21 @@
+module Micropub
+  module Queries
+    module Posts
+      class SyndicationUrlToSource
+        def call(url:)
+          if url.match("https://social.dnitza.com")
+            return :mastodon
+          end
+
+          if url.match("https://bsky.social")
+            return :bluesky
+          end
+
+          if url.match("https://gist.github.com")
+            return :gist
+          end
+        end
+      end
+    end
+  end
+end