The version is a string.

4f33208a · Jean-Paul Calderone · b8336503 · 4f33208a
Commit 4f33208a authored 3 years ago by Jean-Paul Calderone
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -182,7 +182,7 @@ jobs:
            nix-build \
              --argstr hypothesisProfile ci \
              --arg collectCoverage true \
-              --arg tahoe-lafs << parameters.tahoe-version >> \
+              --argstr tahoe-lafs << parameters.tahoe-version >> \
              --attr doc

      - run: