diff --git a/pkgs/by-name/sm/smtp4dev/deps.json b/pkgs/by-name/sm/smtp4dev/deps.json
index 40de6f06d71f..9b2004233e86 100644
--- a/pkgs/by-name/sm/smtp4dev/deps.json
+++ b/pkgs/by-name/sm/smtp4dev/deps.json
@@ -51,13 +51,13 @@
   },
   {
     "pname": "FSharp.Core",
-    "version": "8.0.200",
-    "hash": "sha256-wjYiedFiqOTKaM4mF6uT9kc/yKDJ78mqfw9qLoBFHOw="
+    "version": "8.0.301",
+    "hash": "sha256-LyP+zHxXFNksSQ/ExQ9CGkQYGvld8W6JNmxMg6lTRCs="
   },
   {
     "pname": "Html2Markdown",
-    "version": "6.1.0.2",
-    "hash": "sha256-r8tXLN6rkOCW+Tae+etAgP3MGkW8mQFQetR1ual6trM="
+    "version": "6.2.5.7",
+    "hash": "sha256-9uoXng20APzOMAE1iuJ/I4mb3YE5IDhWTv1eMAMVeRE="
   },
   {
     "pname": "HtmlAgilityPack",
@@ -69,6 +69,11 @@
     "version": "2.14.1",
     "hash": "sha256-EXvojddPu+9JKgOG9NSQgUTfWq1RpOYw7adxDPKDJ6o="
   },
+  {
+    "pname": "JetBrains.Annotations",
+    "version": "2024.2.0",
+    "hash": "sha256-OgtW4wIqo5d3q6NSiYrUm4KkUdUHEWFyvlbtoQJjDwU="
+  },
   {
     "pname": "Jint",
     "version": "3.0.1",
@@ -76,8 +81,8 @@
   },
   {
     "pname": "Linq.Expression.Optimizer",
-    "version": "1.0.29",
-    "hash": "sha256-F0ZvZ6hbdnjkuNuSoFzSjYUgG/hEHuG7o8wExDS1LLo="
+    "version": "1.0.34",
+    "hash": "sha256-CrDmtcpwFDZ/mAj/urtLWXM1ZDTr/msjZPT48YZGleI="
   },
   {
     "pname": "LinqKit",
@@ -1046,8 +1051,8 @@
   },
   {
     "pname": "Serilog.Sinks.Console",
-    "version": "6.0.0",
-    "hash": "sha256-QH8ykDkLssJ99Fgl+ZBFBr+RQRl0wRTkeccQuuGLyro="
+    "version": "6.1.1",
+    "hash": "sha256-CfIg4Us4kSMQAn6rU2rsAeE22g6MpFiZdhoZWySpZeY="
   },
   {
     "pname": "Serilog.Sinks.Debug",
@@ -1061,8 +1066,8 @@
   },
   {
     "pname": "Serilog.Sinks.File",
-    "version": "6.0.0",
-    "hash": "sha256-KQmlUpG9ovRpNqKhKe6rz3XMLUjkBqjyQhEm2hV5Sow="
+    "version": "7.0.0",
+    "hash": "sha256-LxZYUoUPkCjIIVarJilnXnqQiMrFNJtoRilmzTNtUjo="
   },
   {
     "pname": "SQLitePCLRaw.bundle_e_sqlite3",
@@ -1421,8 +1426,8 @@
   },
   {
     "pname": "System.Linq.Dynamic.Core",
-    "version": "1.6.4",
-    "hash": "sha256-Mpp+3UYARo+Hnh3ybtHtdN0LI5HQV07CBZP7jRnVk10="
+    "version": "1.7.1",
+    "hash": "sha256-IOBL8cg9TektJlinbpb9w4scifbFcNiZ7D66NDXthxw="
   },
   {
     "pname": "System.Linq.Expressions",
@@ -1496,8 +1501,8 @@
   },
   {
     "pname": "System.Reactive",
-    "version": "6.0.1",
-    "hash": "sha256-Lo5UMqp8DsbVSUxa2UpClR1GoYzqQQcSxkfyFqB/d4Q="
+    "version": "6.1.0",
+    "hash": "sha256-zACYoZmKxHo0qKY8FOVa7jIsw7dN7WjdXdRRV95qY2Y="
   },
   {
     "pname": "System.Reflection",
diff --git a/pkgs/by-name/sm/smtp4dev/package.nix b/pkgs/by-name/sm/smtp4dev/package.nix
index fae45b8cb86d..5a5242481e10 100644
--- a/pkgs/by-name/sm/smtp4dev/package.nix
+++ b/pkgs/by-name/sm/smtp4dev/package.nix
@@ -11,13 +11,13 @@
 
 buildDotnetModule (finalAttrs: {
   pname = "smtp4dev";
-  version = "3.11.0";
+  version = "3.12.0";
 
   src = fetchFromGitHub {
     owner = "rnwood";
     repo = "smtp4dev";
     tag = finalAttrs.version;
-    hash = "sha256-+6UIfttIjBbsxptc1uI7K8golGwl+Fw6f5kCl89NPDA=";
+    hash = "sha256-1dzK0IHdjEppV62tE4Ywqs8WihLJUY4bhzJPQ1A/Eog=";
   };
 
   patches = [ ./smtp4dev-npm-packages.patch ];
@@ -33,7 +33,7 @@ buildDotnetModule (finalAttrs: {
 
   npmDeps = fetchNpmDeps {
     inherit (finalAttrs) src patches;
-    hash = "sha256-+rKqiGiIQAYCY/3z1m9cQI0WgtdX8UTr70v7nTtgkt0=";
+    hash = "sha256-lJyjoTTgum67j1qPtkLFGYO2sTpvN7ug0Q1jJw/Se/c=";
     postPatch = "cd ${finalAttrs.npmRoot}";
   };