diff --git a/horizon.dhall b/horizon.dhall
index ba1e46b35dd639bda8d19bfdf974a1e7b2889963..dc283af89594a3ed0f0fffec53f28cec71e89c4a 100644
--- a/horizon.dhall
+++ b/horizon.dhall
@@ -784,6 +784,7 @@ let packages =
       , string-qq = H.callHackage "string-qq" "0.0.4"
       , stringbuilder = H.callHackage "stringbuilder" "0.5.1"
       , stringsearch = H.callHackage "stringsearch" "0.3.6.6"
+      , sundown = H.callHackage "sundown" "0.6"
       , swagger2 = H.callHackage "swagger2" "2.8.5"
       , syb = H.callHackage "syb" "0.7.2.1"
       , sydtest = H.callHackage "sydtest" "0.13.0.0"
diff --git a/initial-packages.nix b/initial-packages.nix
index b6df5aba39c84bc65715b7c6dd78a6dca8348d4e..eae597b2ed35e11751d95ea8f714de93c1f55830 100644
--- a/initial-packages.nix
+++ b/initial-packages.nix
@@ -1285,6 +1285,8 @@ self: with pkgs.haskell.lib; {
 
   stringsearch = self.callPackage (./pkgs/stringsearch.nix) { };
 
+  sundown = self.callPackage (./pkgs/sundown.nix) { };
+
   swagger2 = self.callPackage (./pkgs/swagger2.nix) { };
 
   syb = self.callPackage (./pkgs/syb.nix) { };
diff --git a/pkgs/sundown.nix b/pkgs/sundown.nix
new file mode 100644
index 0000000000000000000000000000000000000000..5228731ca447b71997f030e6c9686521189f7e93
--- /dev/null
+++ b/pkgs/sundown.nix
@@ -0,0 +1,21 @@
+{ mkDerivation, base, bytestring, lib, text }:
+mkDerivation {
+  pname = "sundown";
+  version = "0.6";
+  sha256 = "cb9b7e98138311375148ffe0fa4c4b04eb7a9f8ec2ae13a674d465e5d71db027";
+  isLibrary = true;
+  isExecutable = false;
+  enableSeparateDataOutput = false;
+  libraryHaskellDepends = [ base bytestring text ];
+  enableLibraryProfiling = true;
+  enableExecutableProfiling = true;
+  doHaddock = false;
+  jailbreak = true;
+  doCheck = false;
+  doBenchmark = false;
+  hyperlinkSource = false;
+  homepage = "https://github.com/bitonic/sundown";
+  description = "Bindings to the sundown markdown library";
+  license = lib.licenses.publicDomain;
+  broken = false;
+}