diff --git a/.github/workflows/prototyping.yml b/.github/workflows/prototyping.yml
index 495642f3..deb81567 100644
--- a/.github/workflows/prototyping.yml
+++ b/.github/workflows/prototyping.yml
@@ -11,6 +11,7 @@ jobs:
     strategy:
       matrix:
         agda: [2.6.2.1]
+        bytestring: [0.11.1.0]
         scientific: [0.3.7.0]
         vector: [0.12.3.1]
         aeson: [2.0.3.0]
@@ -36,7 +37,7 @@ jobs:
       working-directory: prototyping
       run: |
         cabal install Agda-${{ matrix.agda }}
-        cabal install --lib scientific-${{ matrix.scientific }} vector-${{ matrix.vector }} aeson-${{ matrix.aeson }} --package-env .
+        cabal install --lib bytestring-{{ matrix.bytestring }} scientific-${{ matrix.scientific }} vector-${{ matrix.vector }} aeson-${{ matrix.aeson }} --package-env .
     - name: check targets
       working-directory: prototyping
       run: |