diff --git a/util/bats-assert/Dockerfile b/util/bats-assert/Dockerfile
index 1f6d6ba..f7f0551 100644
--- a/util/bats-assert/Dockerfile
+++ b/util/bats-assert/Dockerfile
@@ -1,7 +1,9 @@
 #syntax=docker/dockerfile:1.8
 #check=error=true
 
-FROM --platform=$BUILDPLATFORM alpine AS build
+ARG ALPINE_VERSION=3.20
+
+FROM --platform=$BUILDPLATFORM alpine:${ALPINE_VERSION} AS build
 RUN apk add --no-cache git
 WORKDIR /work
 RUN git clone --bare https://github.com/ztombol/bats-support && \
@@ -19,7 +21,7 @@ RUN echo 'source "$(dirname "${BASH_SOURCE[0]}")/bats-support/load.bash"' > /out
 FROM scratch AS release
 COPY --from=build /out /
 
-FROM alpine:3.19 AS test-gen
+FROM alpine:${ALPINE_VERSION} AS test-gen
 RUN apk add --no-cache bats
 WORKDIR /work
 COPY --from=release . .
diff --git a/util/bats-assert/test.bats.golden b/util/bats-assert/test.bats.golden
index 13e8830..f7f3aa9 100644
--- a/util/bats-assert/test.bats.golden
+++ b/util/bats-assert/test.bats.golden
@@ -27,5 +27,5 @@ not ok 5 run-fail
 
 The following warnings were encountered during tests:
 BW01: `run`'s command `./foobar` exited with code 127, indicating 'Command not found'. Use run's return code checks, e.g. `run -127`, to fix this message.
-      (from function `run' in file /usr/lib/bats-core/test_functions.bash, line 421,
+      (from function `run' in file /usr/lib/bats-core/test_functions.bash, line 426,
        in test file test.bats, line 15)