diff --git a/ci/alpine/Dockerfile b/ci/alpine/Dockerfile
index 30676c3c4d..ce82ab708f 100644
--- a/ci/alpine/Dockerfile
+++ b/ci/alpine/Dockerfile
@@ -12,6 +12,7 @@ RUN apk add --no-cache \
   cmake \
   curl \
   diffutils \
+  dnsmasq \
   flex-dev \
   musl-fts-dev \
   g++ \
diff --git a/ci/debian-12/Dockerfile b/ci/debian-12/Dockerfile
index f989f4e28a..c3ae4339b7 100644
--- a/ci/debian-12/Dockerfile
+++ b/ci/debian-12/Dockerfile
@@ -12,6 +12,7 @@ RUN apt-get update && apt-get -y install \
     ccache \
     cmake \
     curl \
+    dnsmasq \
     flex \
     g++ \
     gcc \
diff --git a/ci/fedora-40/Dockerfile b/ci/fedora-40/Dockerfile
index f292e11ece..45f209dbec 100644
--- a/ci/fedora-40/Dockerfile
+++ b/ci/fedora-40/Dockerfile
@@ -9,6 +9,7 @@ RUN dnf -y install \
     ccache \
     cmake \
     diffutils \
+    dnsmasq \
     flex \
     gcc \
     gcc-c++ \
diff --git a/ci/freebsd/prepare.sh b/ci/freebsd/prepare.sh
index 629ed3c513..5051084ac3 100755
--- a/ci/freebsd/prepare.sh
+++ b/ci/freebsd/prepare.sh
@@ -6,7 +6,7 @@ set -e
 set -x
 
 env ASSUME_ALWAYS_YES=YES pkg bootstrap
-pkg install -y bash git cmake swig bison python3 base64 flex ccache jq
+pkg install -y bash git cmake swig bison python3 base64 flex ccache jq dnsmasq
 pkg upgrade -y curl
 pyver=$(python3 -c 'import sys; print(f"py{sys.version_info[0]}{sys.version_info[1]}")')
 pkg install -y $pyver-sqlite3
@@ -17,3 +17,6 @@ python -m pip install websockets junit2html
 # Spicy detects whether it is run from build directory via `/proc`.
 echo "proc /proc procfs rw,noauto 0 0" >>/etc/fstab
 mount /proc
+
+# dnsmasq is in /usr/local/sbin and that's not in the PATH by default
+ln -s /usr/local/sbin/dnsmasq /usr/local/bin/dnsmasq
diff --git a/ci/macos/prepare.sh b/ci/macos/prepare.sh
index a96833f75f..7cc3e69cac 100755
--- a/ci/macos/prepare.sh
+++ b/ci/macos/prepare.sh
@@ -7,7 +7,7 @@ set -x
 
 brew update
 brew upgrade cmake
-brew install openssl@3 swig bison flex ccache libmaxminddb
+brew install openssl@3 swig bison flex ccache libmaxminddb dnsmasq
 
 if [ $(sw_vers -productVersion | cut -d '.' -f 1) -lt 14 ]; then
     python3 -m pip install --upgrade pip
diff --git a/ci/opensuse-leap-15.6/Dockerfile b/ci/opensuse-leap-15.6/Dockerfile
index 359c282f01..a40405e855 100644
--- a/ci/opensuse-leap-15.6/Dockerfile
+++ b/ci/opensuse-leap-15.6/Dockerfile
@@ -11,6 +11,7 @@ RUN zypper addrepo https://download.opensuse.org/repositories/openSUSE:Leap:15.6
     ccache \
     cmake \
     curl \
+    dnsmasq \
     flex \
     gcc12 \
     gcc12-c++ \
diff --git a/ci/opensuse-tumbleweed/Dockerfile b/ci/opensuse-tumbleweed/Dockerfile
index 911f7af96b..c35a80205a 100644
--- a/ci/opensuse-tumbleweed/Dockerfile
+++ b/ci/opensuse-tumbleweed/Dockerfile
@@ -16,6 +16,7 @@ RUN zypper refresh \
     cmake \
     curl \
     diffutils \
+    dnsmasq \
     findutils \
     flex \
     gcc \
diff --git a/ci/ubuntu-24.04/Dockerfile b/ci/ubuntu-24.04/Dockerfile
index 13dbac92cf..89d999d19c 100644
--- a/ci/ubuntu-24.04/Dockerfile
+++ b/ci/ubuntu-24.04/Dockerfile
@@ -15,6 +15,7 @@ RUN apt-get update && apt-get -y install \
     clang++-18 \
     cmake \
     curl \
+    dnsmasq \
     flex \
     g++ \
     gcc \