diff --git a/.circleci/config.yml b/.circleci/config.yml
index 8f88565d..12666ec4 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -16,7 +16,7 @@ version: 2.1
 
 orbs:
   # Get easier access to the Windows machine executor.
-  win: "circleci/windows@4.1.1"
+  win: "circleci/windows@5.0"
 
 aliases:
   - &PREPARE_VIRTUALENV
@@ -81,7 +81,7 @@ jobs:
       size: "medium"
       # The default Windows machine image changes from time to time - which
       # often breaks things.  Avoid that.
-      version: "2022.08.1"
+      # version: "2022.08.1"
 
     steps:
       # Commands are run in a Windows virtual machine environment
@@ -507,7 +507,7 @@ workflows:
               - "3.9"
               - "3.10"
             xcode-version:
-              - "12.5.1"
+              - "13.4.1"
 
     - "windows-tests":
         matrix:
@@ -523,7 +523,7 @@ workflows:
           - "linux-tests-39-dev"
           - "linux-tests-310-1_17_1"
           - "linux-tests-310-dev"
-          - "macos-tests-3.9-12.5.1"
-          - "macos-tests-3.10-12.5.1"
+          - "macos-tests-3.9-13.4.1"
+          - "macos-tests-3.10-13.4.1"
           - "windows-tests-3.9"
           - "windows-tests-3.10"
diff --git a/setup.cfg b/setup.cfg
index a90b6386..ae995224 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -52,7 +52,7 @@ install_requires =
     # basically no wiggle room here.  We use a tiny range that just covers
     # what we test plus a little because our Nix packaging provides a
     # Tahoe-LAFS with a .postNNN version.
-    tahoe-lafs >=1.17.1,<1.18.1
+    tahoe-lafs >=1.17.1,<1.19.1
     treq
     pyutil
     prometheus-client