diff --git a/.woodpecker/build_bin.yml b/.woodpecker/build_bin.yml
index 5de56b2..4ce4725 100644
--- a/.woodpecker/build_bin.yml
+++ b/.woodpecker/build_bin.yml
@@ -1,9 +1,13 @@
 pipeline:
   bin-pack:
-    image: debian:stable-slim
+    image: debian-pack:0.1
+    secrets:
+      - WEBDAV_USER
+      - WEBDAV_PASS
+      - WEBDAV_HOST
+      - WEBDAV_REPOPATH
     commands:
-      - source script/build_single.sh
-      - build_single ${BIN_PACK}
+      - ./script/build_single.sh $BIN_PACK
 
 matrix:
   BIN_PACK:
diff --git a/.woodpecker/build_other.yml b/.woodpecker/build_other.yml
index 1f00c3f..3904905 100644
--- a/.woodpecker/build_other.yml
+++ b/.woodpecker/build_other.yml
@@ -1,13 +1,21 @@
 pipeline:
   dendrite:
     image: golang
+    secrets:
+      - WEBDAV_USER
+      - WEBDAV_PASS
+      - WEBDAV_HOST
+      - WEBDAV_REPOPATH
     commands:
-      - source script/build_single.sh
-      - build_single dendrite
+      - ./script/build_single.sh dendrite
 
   static-deployer-git:
-    image: debian:stable-slim
+    image: debian-pack:0.1
+    secrets:
+      - WEBDAV_USER
+      - WEBDAV_PASS
+      - WEBDAV_HOST
+      - WEBDAV_REPOPATH
     commands:
-      - source script/build_single.sh
-      - build_single static-deployer-git
+      - ./script/build_single.sh static-deployer-git
 
diff --git a/.woodpecker/debian-pack.df b/.woodpecker/debian-pack.df
new file mode 100644
index 0000000..57748af
--- /dev/null
+++ b/.woodpecker/debian-pack.df
@@ -0,0 +1,6 @@
+FROM debian:bullseye-slim
+
+RUN apt update && \
+    apt install --yes curl ca-certificates && \
+    apt clean && \
+    rm -rf /var/lib/apt/lists/*
diff --git a/script/build_all.sh b/script/build_all.sh
old mode 100644
new mode 100755
index f5a9377..e4b9445
--- a/script/build_all.sh
+++ b/script/build_all.sh
@@ -1,53 +1,6 @@
 #!/usr/bin/evn bash
-#
-set -o pipefail
-set -o errexit
-set -o errtrace
-
-WEBDAV_USER=${WEBDAV_USER:?WEBDAV_USER not set}
-WEBDAV_PASS=${WEBDAV_PASS:?WEBDAV_PASS not set}
-WEBDAV_HOST=${WEBDAV_HOST:?WEBDAV_HOST not set}
-WEBDAV_REPOPATH=${WEBDAV_REPOPATH:?WEBDAV_REPOPATH not set}
-
-function curl_alias {
-    curl --show-error --silent --user "${WEBDAV_USER}:${WEBDAV_PASS}" "$@"
-}
-
-function webdav_is_file_exists {
-    local target="${1%/}"
-    local target="${target#/}"
-    local resp=$(curl_alias --head --write-out "%{http_code}" "${WEBDAV_HOST}/${WEBDAV_REPOPATH}/${target}" | tail -n 1)
-    [[ "${resp}" == "200" ]]
-}
-
-function webdav_mkcol {
-    local dirname="${1#/}"
-    curl_alias --request MKCOL "${WEBDAV_HOST}/${dirname}"
-}
-
-function webdav_upload_file {
-    curl_alias --silent --upload-file "$1" "${WEBDAV_HOST}/${WEBDAV_REPOPATH}/$2"
-    echo "file $1 uploaded to ${WEBDAV_HOST}/${WEBDAV_REPOPATH}/$2"
-}
-
-function build_single {
-    (
-        local package_name="$1"
-        local package_path="$(realpath "$1")"
-        cd "$package_path"
-        local target_filename="$(../makedeb/makedeb -STF | tail -n 1)"
-
-        if webdav_is_file_exists "${target_filename}" ; then
-            echo "${package_name} already built, skipped."
-            return
-        fi
-
-        ../makedeb/makedeb
-
-        webdav_upload_file "${target_filename}" "${target_filename}"
-    )
-}
 
+source $(dirname $0)/util.sh
 
 for i in $(find . -maxdepth 1 -mindepth 1 -type d -not -path './script' -not -path './makedeb' -not -name '.*')
 do
diff --git a/script/build_single.sh b/script/build_single.sh
new file mode 100755
index 0000000..0a44f67
--- /dev/null
+++ b/script/build_single.sh
@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+
+source $(dirname $0)/util.sh
+
+build_single $1
diff --git a/script/util.sh b/script/util.sh
new file mode 100644
index 0000000..8abae24
--- /dev/null
+++ b/script/util.sh
@@ -0,0 +1,49 @@
+#!/usr/bin/evn bash
+#
+set -o pipefail
+set -o errexit
+set -o errtrace
+
+WEBDAV_USER=${WEBDAV_USER:?WEBDAV_USER not set}
+WEBDAV_PASS=${WEBDAV_PASS:?WEBDAV_PASS not set}
+WEBDAV_HOST=${WEBDAV_HOST:?WEBDAV_HOST not set}
+WEBDAV_REPOPATH=${WEBDAV_REPOPATH:?WEBDAV_REPOPATH not set}
+
+function curl_alias {
+    curl --show-error --silent --user "${WEBDAV_USER}:${WEBDAV_PASS}" "$@"
+}
+
+function webdav_is_file_exists {
+    local target="${1%/}"
+    local target="${target#/}"
+    local resp=$(curl_alias --head --write-out "%{http_code}" "${WEBDAV_HOST}/${WEBDAV_REPOPATH}/${target}" | tail -n 1)
+    [[ "${resp}" == "200" ]]
+}
+
+function webdav_mkcol {
+    local dirname="${1#/}"
+    curl_alias --request MKCOL "${WEBDAV_HOST}/${dirname}"
+}
+
+function webdav_upload_file {
+    curl_alias --silent --upload-file "$1" "${WEBDAV_HOST}/${WEBDAV_REPOPATH}/$2"
+    echo "file $1 uploaded to ${WEBDAV_HOST}/${WEBDAV_REPOPATH}/$2"
+}
+
+function build_single {
+    (
+        local package_name="$1"
+        local package_path="$(realpath "$1")"
+        cd "$package_path"
+        local target_filename="$(../makedeb/makedeb -STF | tail -n 1)"
+
+        if webdav_is_file_exists "${target_filename}" ; then
+            echo "${package_name} already built, skipped."
+            return
+        fi
+
+        ../makedeb/makedeb
+
+        webdav_upload_file "${target_filename}" "${target_filename}"
+    )
+}