diff --git a/pkgs/development/python-modules/awslambdaric/default.nix b/pkgs/development/python-modules/awslambdaric/default.nix
index db55543ca5a3..6bb6702b1e2b 100644
--- a/pkgs/development/python-modules/awslambdaric/default.nix
+++ b/pkgs/development/python-modules/awslambdaric/default.nix
@@ -3,14 +3,14 @@
 
 buildPythonPackage rec {
   pname = "awslambdaric";
-  version = "1.1.1";
+  version = "1.2.0";
   disabled = isPy27;
 
   src = fetchFromGitHub {
     owner = "aws";
     repo = "aws-lambda-python-runtime-interface-client";
     rev = version;
-    sha256 = "1f8828y32yrf87bc933jhmjrvj746baibvpn0w21x3ji81vf6mri";
+    sha256 = "120qar8iaxj6dmnhjw1c40n2w06f1nyxy57dwh06xdiany698fg4";
   };
 
   propagatedBuildInputs = [ simplejson ];
@@ -21,6 +21,10 @@ buildPythonPackage rec {
 
   dontUseCmakeConfigure = true;
 
+  preBuild = ''
+    substituteInPlace requirements/base.txt --replace 'simplejson==3' 'simplejson~=3'
+  '';
+
   checkInputs = [ pytestCheckHook ];
 
   pythonImportsCheck = [ "awslambdaric" "runtime_client" ];