diff --git a/.circleci/config.yml b/.circleci/config.yml
index 3625ecd43..4971f6d75 100755
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -69,7 +69,7 @@ executors:
       #
       # It runs as uid 1000 "heroku" with no sudo, so every step below
       # must work unelevated. That is why Ruby goes in $HOME.
-      - image: heroku/heroku:24-build@sha256:a6e743f508a2f37f90ddd551587c3a0776529219ae427296db8836fa9a680275
+      - image: heroku/heroku:26-build@sha256:2c501bb3e9aba5b6c44c4dac9a867a6b6d72032b29e556c7d41241c411059798
         environment:
           PG_HOST: localhost
           PG_USER: ubuntu
@@ -150,7 +150,7 @@ executors:
   # sharing the prepare_ruby command.
   ruby-only:
     docker:
-      - image: heroku/heroku:24-build@sha256:a6e743f508a2f37f90ddd551587c3a0776529219ae427296db8836fa9a680275
+      - image: heroku/heroku:26-build@sha256:2c501bb3e9aba5b6c44c4dac9a867a6b6d72032b29e556c7d41241c411059798
         environment:
           RAILS_ENV: test
           RACK_ENV: test