diff --git a/circle.yml b/circle.yml
index 9b56ce82..9e8c3986 100644
--- a/circle.yml
+++ b/circle.yml
@@ -19,9 +19,9 @@ commands:
 
 jobs:
 
-  go120:
+  go121:
     docker:
-      - image: cimg/go:1.20
+      - image: cimg/go:1.21
     steps:
       - run:
           name: "Install tools"
@@ -76,6 +76,13 @@ jobs:
           name: "Test (PPC64 emulation)"
           command: qemu-ppc64-static uint256.test.ppc64 -test.v
 
+  go120:
+    docker:
+      - image: cimg/go:1.20
+    steps:
+      - checkout
+      - test
+
   go119:
     docker:
       - image: cimg/go:1.19
@@ -85,13 +92,13 @@ jobs:
 
 
 
-
 workflows:
   version: 2
   uint256:
     jobs:
+      - go121
       - go120
       - go119
       - bigendian:
           requires:
-            - go120
+            - go121
diff --git a/go.mod b/go.mod
index 26425ac6..92c444c8 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,3 @@
 module github.com/holiman/uint256
 
-go 1.18
+go 1.19