diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 606284d1..f5f0150b 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -16,7 +16,7 @@ jobs:
       - name: Install dependencies
         run: |
           apt update
-          apt install make gcc sdcc xxd python-is-python3 libjson-c-dev -y
+          apt install make gcc sdcc xxd python-is-python3 libjson-c-dev zlib1g-dev -y
       - name: Check if machine.c can be compiled for all machines
         run: make machine_check
       - name: Make project