diff --git a/pkgs/development/libraries/openfst/default.nix b/pkgs/development/libraries/openfst/default.nix
index 51e661eabb3b..08767680ffd6 100644
--- a/pkgs/development/libraries/openfst/default.nix
+++ b/pkgs/development/libraries/openfst/default.nix
@@ -2,11 +2,11 @@
 
 stdenv.mkDerivation rec {
   pname = "openfst";
-  version = "1.7.9";
+  version = "1.8.1";
 
   src = fetchurl {
     url = "http://www.openfst.org/twiki/pub/FST/FstDownload/${pname}-${version}.tar.gz";
-    sha256 = "1pmx1yhn2gknj0an0zwqmzgwjaycapi896244np50a8y3nrsw6ck";
+    sha256 = "sha256-JPtTtyu2h+P6julscqMf8pINmbmAoKj2HdpCb8pnE/A=";
   };
 
   configureFlags = [
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 2a4e05889920..741e8eed9c5f 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -32977,7 +32977,16 @@ with pkgs;
     python = python3;
   };
 
-  phonetisaurus = callPackage ../development/libraries/phonetisaurus {};
+  phonetisaurus = callPackage ../development/libraries/phonetisaurus {
+    # https://github.com/AdolfVonKleist/Phonetisaurus/issues/70
+    openfst = openfst.overrideAttrs (_: rec {
+      version = "1.7.9";
+      src = fetchurl {
+        url = "http://www.openfst.org/twiki/pub/FST/FstDownload/openfst-${version}.tar.gz";
+        sha256 = "1pmx1yhn2gknj0an0zwqmzgwjaycapi896244np50a8y3nrsw6ck";
+      };
+    });
+  };
 
   duti = callPackage ../os-specific/darwin/duti {
     inherit (darwin.apple_sdk.frameworks) ApplicationServices;