diff --git a/readme.md b/readme.md
index c8ab4a9..8bb324b 100644
--- a/readme.md
+++ b/readme.md
@@ -217,11 +217,18 @@ Handle project workflows in a unified way:
   * constants for characters
   * dynamic substeps
 * comment
-* review repositories handling for systems
-  * opensuse
-    * codecs repository
-    * disable & enable https
+* frame corners
+* packages
+  * configure
+    * apk
+    * pacman
+    * zypper
+  * repositories
+    * opensuse
+      * codecs repository
+      * disable & enable https
 * test
+* underscore internals
 
 ### Shell → Python
 
diff --git a/spcd/bootstrap.sh b/spcd/bootstrap.sh
index c2320ba..db3dcb3 100644
--- a/spcd/bootstrap.sh
+++ b/spcd/bootstrap.sh
@@ -405,11 +405,6 @@ SPCD_OS_OPENSUSE="opensuse"
 SPCD_OS_ROCKY="rocky"
 SPCD_OS_UBUNTU="ubuntu"
 
-SPCD_PF_APK="apk"
-SPCD_PF_DEB="deb"
-SPCD_PF_PKG="pkg"
-SPCD_PF_RPM="rpm"
-
 SPCD_PM_APK="apk"
 SPCD_PM_APT="apt"
 SPCD_PM_DNF="dnf"
@@ -596,39 +591,9 @@ ${SPCD_PROJECT_ROOT}$(basename "${GITHUB_SERVER_URL}")"
     spcd_os_printenv "SPCD_OS_ID" "SPCD_OS_VERSION"
     # universal
     SPCD_DNS_FILE="/etc/resolv.conf"
-    SPCD_PKG_CA="ca-certificates"
-    SPCD_PKG_DOS2UNIX="dos2unix"
-    SPCD_PKG_GIT="git"
     SPCD_PYTHON_ALIAS="python3"
     spcd_split
-    spcd_os_printenv "SPCD_DNS_FILE" \
-        "SPCD_PKG_CA" "SPCD_PKG_DOS2UNIX" "SPCD_PKG_GIT" "SPCD_PYTHON_ALIAS"
-    # set ca command & root
-    case "${SPCD_OS_ID}" in
-    "${SPCD_OS_ALMA}" | "${SPCD_OS_FEDORA}" | "${SPCD_OS_ROCKY}")
-        SPCD_CA_ROOT="/etc/pki/ca-trust/source/anchors"
-        SPCD_CMD_CA="update-ca-trust"
-        ;;
-    "${SPCD_OS_ALPINE}")
-        SPCD_CA_ROOT="/usr/local/share/ca-certificates"
-        SPCD_CMD_CA="update-ca-certificates"
-        ;;
-    "${SPCD_OS_ARCH}")
-        SPCD_CA_ROOT="/etc/ca-certificates/trust-source/anchors"
-        SPCD_CMD_CA="update-ca-trust"
-        ;;
-    "${SPCD_OS_DEBIAN}" | "${SPCD_OS_UBUNTU}")
-        SPCD_CA_ROOT="/usr/local/share/ca-certificates"
-        SPCD_CMD_CA="update-ca-certificates"
-        ;;
-    "${SPCD_OS_OPENSUSE}")
-        SPCD_CA_ROOT="/etc/pki/trust/anchors"
-        SPCD_CMD_CA="update-ca-certificates"
-        ;;
-    *) ;;
-    esac
-    spcd_split
-    spcd_os_printenv "SPCD_CA_ROOT" "SPCD_CMD_CA"
+    spcd_os_printenv "SPCD_DNS_FILE" "SPCD_PYTHON_ALIAS"
     # set package manager
     case "${SPCD_OS_ID}" in
     "${SPCD_OS_ALPINE}")
@@ -648,105 +613,35 @@ ${SPCD_PROJECT_ROOT}$(basename "${GITHUB_SERVER_URL}")"
         ;;
     *) ;;
     esac
-    # set package format
-    case "${SPCD_PM}" in
-    "${SPCD_PM_APK}")
-        SPCD_PF="${SPCD_PF_APK}"
-        ;;
-    "${SPCD_PM_APT}")
-        SPCD_PF="${SPCD_PF_DEB}"
-        ;;
-    "${SPCD_PM_PACMAN}")
-        SPCD_PF="${SPCD_PF_PKG}"
-        ;;
-    "${SPCD_PM_DNF}" | "${SPCD_PM_ZYPPER}")
-        SPCD_PF="${SPCD_PF_RPM}"
-        ;;
-    *) ;;
-    esac
     # set package manager variables
     spcd_split
-    spcd_os_printenv "SPCD_PF" "SPCD_PM"
+    spcd_os_printenv "SPCD_PM"
     case "${SPCD_PM}" in
     "${SPCD_PM_DNF}")
-        SPCD_PM_CLEAN="dnf clean all"
-        SPCD_PM_INSTALL="dnf install --assumeyes"
-        SPCD_PM_QUERY="rpm --query"
-        SPCD_PM_UPDATE="dnf makecache"
-        SPCD_PM_UPGRADE="dnf upgrade --assumeyes"
-        SPCD_PKG_PKG=""
-        SPCD_PM_CONF_PATH="/etc/dnf/dnf.conf"
-        SPCD_PM_CONF_TEXT="\
-[main]
-best=True
-clean_requirements_on_remove=True
-gpgcheck=1
-installonly_limit=3
-skip_if_unavailable=False
-"
         SPCD_PM_HTTPS_PATH="/etc/dnf/dnf.conf.d/https.conf"
         SPCD_PM_HTTPS_TEXT="\
 sslverify=False
 "
         ;;
     "${SPCD_PM_APK}")
-        SPCD_PM_CLEAN="apk cache purge"
-        SPCD_PM_INSTALL="apk add"
-        SPCD_PM_QUERY="apk info"
-        SPCD_PM_UPDATE="apk update"
-        SPCD_PM_UPGRADE="apk upgrade"
-        SPCD_PKG_PKG=""
-        SPCD_PM_CONF_PATH=""
-        SPCD_PM_CONF_TEXT=""
         SPCD_PM_HTTPS_PATH="/etc/apk/repositories.d/https"
         SPCD_PM_HTTPS_TEXT="\
 --no-verify
 "
         ;;
     "${SPCD_PM_PACMAN}")
-        SPCD_PM_CLEAN="pacman --sync --clean --noconfirm"
-        SPCD_PM_INSTALL="pacman --sync --noconfirm"
-        SPCD_PM_QUERY="pacman --query"
-        SPCD_PM_UPDATE="pacman --sync --refresh"
-        SPCD_PM_UPGRADE="pacman --sync --sysupgrade --noconfirm"
-        SPCD_PKG_PKG=""
-        SPCD_PM_CONF_PATH=""
-        SPCD_PM_CONF_TEXT=""
         SPCD_PM_HTTPS_PATH="/etc/pacman.d/https.conf"
         SPCD_PM_HTTPS_TEXT="\
 SSLVerify = No
 "
         ;;
     "${SPCD_PM_APT}")
-        SPCD_PM_CLEAN="apt-get clean"
-        SPCD_PM_INSTALL="apt-get install --assume-yes"
-        SPCD_PM_QUERY="dpkg-query --show"
-        SPCD_PM_UPDATE="apt-get update"
-        SPCD_PM_UPGRADE="apt-get upgrade --assume-yes"
-        SPCD_PKG_PKG="apt-utils"
-        SPCD_PM_CONF_PATH="/etc/apt/apt.conf.d/apt.conf"
-        SPCD_PM_CONF_TEXT="\
-Acquire::Check-Valid-Until True;
-APT::Get::Show-Versions True;
-APT::Install-Recommends False;
-APT::Install-Suggests False;
-Dir::Etc::SourceParts \"\";
-"
         SPCD_PM_HTTPS_PATH="/etc/apt/apt.conf.d/https"
         SPCD_PM_HTTPS_TEXT="\
 Acquire::https::Verify-Peer False;
 "
         ;;
     "${SPCD_PM_ZYPPER}")
-        SPCD_PM_CLEAN="zypper clean"
-        SPCD_PM_INSTALL="zypper --non-interactive install"
-        SPCD_PM_QUERY="rpm --query"
-        SPCD_PM_UPDATE="zypper refresh"
-        SPCD_PM_UPGRADE="zypper --non-interactive update"
-        SPCD_PKG_PKG=""
-        SPCD_PM_CONF_PATH=""
-        SPCD_PM_CONF_TEXT="\
-"
         SPCD_PM_HTTPS_PATH=""
         SPCD_PM_HTTPS_TEXT="\
 "
@@ -754,10 +649,7 @@ Acquire::https::Verify-Peer False;
     *) ;;
     esac
     spcd_split
-    spcd_os_printenv "SPCD_PM_CLEAN" \
-        "SPCD_PM_INSTALL" "SPCD_PM_QUERY" "SPCD_PM_UPDATE" "SPCD_PM_UPGRADE"
-    spcd_split
-    spcd_os_printenv "SPCD_PKG_PKG" "SPCD_PM_CONF_PATH" "SPCD_PM_HTTPS_PATH"
+    spcd_os_printenv "SPCD_PM_HTTPS_PATH"
     # specific
     case "${SPCD_OS_ID}" in
     "${SPCD_OS_ALMA}")
@@ -895,13 +787,10 @@ Acquire::https::Verify-Peer False;
 ${SPCD_PYTHON_VENV}/lib/${SPCD_PYTHON_COMMAND}/site-packages"
     spcd_split
     spcd_os_printenv "SPCD_PYTHON_PACKAGES" "SPCD_PYTHON_VENV_PACKAGES"
-    # variables
-    # certificate authorities
-    [ -n "${SPCD_CA_1}" ] && SPCD_CA=true
     # downloads
     SPCD_DL="$(mktemp --directory)"
     spcd_split
-    spcd_os_printenv "SPCD_CA" "SPCD_DL"
+    spcd_os_printenv "SPCD_DL"
 }
 
 spcd_environment_list_workspace() {
@@ -914,12 +803,38 @@ spcd_environment_list_workspace() {
 # │ steps │ functions │
 # ╰───────┴───────────╯
 
+spcd_clean_cache() {
+    case "${SPCD_PM}" in
+    "${SPCD_PM_APK}") apk cache purge ;;
+    "${SPCD_PM_APT}") apt-get clean ;;
+    "${SPCD_PM_DNF}") dnf clean all ;;
+    "${SPCD_PM_PACMAN}") pacman --sync --clean --noconfirm ;;
+    "${SPCD_PM_ZYPPER}") zypper clean ;;
+    *) ;;
+    esac
+}
+
 spcd_install_package() {
-    spcd_install_package__name="${1}"
-    if [ -n "${spcd_install_package__name}" ]; then
-        ${SPCD_PM_INSTALL} "${spcd_install_package__name}"
-        ${SPCD_PM_CLEAN}
-    fi
+    case "${SPCD_PM}" in
+    "${SPCD_PM_APK}") apk add "${1}" ;;
+    "${SPCD_PM_APT}") apt-get install --assume-yes "${1}" ;;
+    "${SPCD_PM_DNF}") dnf install --assumeyes "${1}" ;;
+    "${SPCD_PM_PACMAN}") pacman --sync --noconfirm "${1}" ;;
+    "${SPCD_PM_ZYPPER}") zypper --non-interactive install "${1}" ;;
+    *) ;;
+    esac
+    spcd_clean_cache
+}
+
+spcd_query_package() {
+    case "${SPCD_PM}" in
+    "${SPCD_PM_APK}") apk info "${1}" ;;
+    "${SPCD_PM_APT}") dpkg-query --show "${1}" ;;
+    "${SPCD_PM_DNF}") rpm --query "${1}" ;;
+    "${SPCD_PM_PACMAN}") pacman --query "${1}" ;;
+    "${SPCD_PM_ZYPPER}") rpm --query "${1}" ;;
+    *) ;;
+    esac
 }
 
 # ╭───────┬─────╮
@@ -1012,7 +927,34 @@ deb ${SPCD_URL_CHOSEN} ${SPCD_OS_VERSION}-security main universe
 
 spcd_packages_set_configuration() {
     spcd_step "Set configuration"
-    spcd_os_write "${SPCD_PM_CONF_PATH}" "${SPCD_PM_CONF_TEXT}"
+    case "${SPCD_PM}" in
+    "${SPCD_PM_DNF}")
+        spcd_os_write "/etc/dnf/dnf.conf" "\
+[main]
+best=True
+clean_requirements_on_remove=True
+gpgcheck=1
+installonly_limit=3
+skip_if_unavailable=False
+"
+        ;;
+    "${SPCD_PM_APK}")
+        ;;
+    "${SPCD_PM_PACMAN}")
+        ;;
+    "${SPCD_PM_APT}")
+        spcd_os_write "/etc/apt/apt.conf.d/apt.conf" "\
+Acquire::Check-Valid-Until True;
+APT::Get::Show-Versions True;
+APT::Install-Recommends False;
+APT::Install-Suggests False;
+Dir::Etc::SourceParts \"\";
+"
+        ;;
+    "${SPCD_PM_ZYPPER}")
+        ;;
+    *) ;;
+    esac
     case "${SPCD_OS_ID}" in
     "${SPCD_OS_ARCH}")
         pacman-key --init
@@ -1026,7 +968,7 @@ spcd_packages_set_configuration() {
 
 spcd_packages_trust_https() {
     spcd_step "Trust HTTPS"
-    if [ -n "${SPCD_CA}" ] || [ "${SPCD_PM}" = "${SPCD_PM_APT}" ]; then
+    if [ -n "${SPCD_CA_1}" ] || [ "${SPCD_PM}" = "${SPCD_PM_APT}" ]; then
         spcd_os_mkdir "$(dirname "${SPCD_PM_HTTPS_PATH}")"
         spcd_os_write "${SPCD_PM_HTTPS_PATH}" "${SPCD_PM_HTTPS_TEXT}"
     fi
@@ -1034,12 +976,22 @@ spcd_packages_trust_https() {
 
 spcd_packages_update_catalog() {
     spcd_step "Update catalog"
-    ${SPCD_PM_UPDATE}
+    case "${SPCD_PM}" in
+    "${SPCD_PM_APK}") apk update ;;
+    "${SPCD_PM_APT}") apt-get update ;;
+    "${SPCD_PM_DNF}") dnf makecache ;;
+    "${SPCD_PM_PACMAN}") pacman --sync --refresh ;;
+    "${SPCD_PM_ZYPPER}") zypper refresh ;;
+    *) ;;
+    esac
 }
 
 spcd_packages_install_tools() {
     spcd_step "Install tools"
-    spcd_install_package "${SPCD_PKG_PKG}"
+    case "${SPCD_PM}" in
+    "${SPCD_PM_APT}") spcd_install_package "apt-utils" ;;
+    *) ;;
+    esac
 }
 
 # ╭───────┬────╮
@@ -1048,17 +1000,32 @@ spcd_packages_install_tools() {
 
 spcd_ca_install_package() {
     spcd_step "Install package"
-    spcd_install_package "${SPCD_PKG_CA}"
+    spcd_install_package "ca-certificates"
 }
 
 spcd_ca_write_certificates() {
     spcd_step "Write certificates"
-    spcd_os_mkdir "${SPCD_CA_ROOT}"
+    case "${SPCD_OS_ID}" in
+    "${SPCD_OS_ALMA}" | "${SPCD_OS_FEDORA}" | "${SPCD_OS_ROCKY}")
+        spcd_wcc__root="/etc/pki/ca-trust/source/anchors"
+        ;;
+    "${SPCD_OS_ALPINE}" | "${SPCD_OS_DEBIAN}" | "${SPCD_OS_UBUNTU}")
+        spcd_wcc__root="/usr/local/share/ca-certificates"
+        ;;
+    "${SPCD_OS_ARCH}")
+        spcd_wcc__root="/etc/ca-certificates/trust-source/anchors"
+        ;;
+    "${SPCD_OS_OPENSUSE}")
+        spcd_wcc__root="/etc/pki/trust/anchors"
+        ;;
+    *) ;;
+    esac
+    spcd_os_mkdir "${spcd_wcc__root}"
     while true; do
         spcd_wcc__index=$((spcd_wcc__index + 1))
         eval "spcd_wcc__text=\"\${SPCD_CA_${spcd_wcc__index}}\""
         [ -n "${spcd_wcc__text}" ] || break
-        spcd_wcc__path="${SPCD_CA_ROOT}/${spcd_wcc__index}.crt"
+        spcd_wcc__path="${spcd_wcc__root}/${spcd_wcc__index}.crt"
         spcd_split
         spcd_os_write "${spcd_wcc__path}" "${spcd_wcc__text}"
         spcd_openssl_x509 "${spcd_wcc__path}"
@@ -1067,7 +1034,21 @@ spcd_ca_write_certificates() {
 
 spcd_ca_update_certificates() {
     spcd_step "Update certificates"
-    ${SPCD_CMD_CA}
+    case "${SPCD_OS_ID}" in
+    "${SPCD_OS_ARCH}" | \
+        "${SPCD_OS_ALMA}" | \
+        "${SPCD_OS_FEDORA}" | \
+        "${SPCD_OS_ROCKY}")
+        update-ca-trust
+        ;;
+    "${SPCD_OS_ALPINE}" | \
+        "${SPCD_OS_DEBIAN}" | \
+        "${SPCD_OS_OPENSUSE}" | \
+        "${SPCD_OS_UBUNTU}")
+        update-ca-certificates
+        ;;
+    *) ;;
+    esac
 }
 
 # ╭───────┬──────────╮
@@ -1081,17 +1062,24 @@ spcd_packages_verify_https() {
 
 spcd_packages_upgrade_system() {
     spcd_step "Upgrade system"
-    ${SPCD_PM_UPGRADE}
+    case "${SPCD_PM}" in
+    "${SPCD_PM_APK}") apk upgrade ;;
+    "${SPCD_PM_APT}") apt-get upgrade --assume-yes ;;
+    "${SPCD_PM_DNF}") dnf upgrade --assumeyes ;;
+    "${SPCD_PM_PACMAN}") pacman --sync --sysupgrade --noconfirm ;;
+    "${SPCD_PM_ZYPPER}") zypper --non-interactive update ;;
+    *) ;;
+    esac
 }
 
 spcd_packages_install_dos2unix() {
     spcd_step "Install dos2unix"
-    spcd_install_package "${SPCD_PKG_DOS2UNIX}"
+    spcd_install_package "dos2unix"
 }
 
 spcd_packages_install_git() {
     spcd_step "Install Git"
-    spcd_install_package "${SPCD_PKG_GIT}"
+    spcd_install_package "git"
 }
 
 # ╭───────┬────────╮
@@ -1166,9 +1154,6 @@ spcd_install_packages() {
         ;;
     *) ;;
     esac
-    # bats
-    spcd_step "BATS"
-    spcd_install_package "bats"
     # graphviz
     spcd_step "GraphViz"
     spcd_install_package "graphviz"
@@ -1192,8 +1177,8 @@ spcd_install_packages() {
     spcd_install_package "rsync"
     # shell check
     spcd_step "ShellCheck"
-    case "${SPCD_PF}" in
-    "${SPCD_PF_RPM}")
+    case "${SPCD_PM}" in
+    "${SPCD_PM_DNF}" | "${SPCD_PM_ZYPPER}")
         spcd_install_package "ShellCheck"
         ;;
     *) spcd_install_package "shellcheck" ;;
@@ -1224,7 +1209,7 @@ spcd_python_write_module() {
         spcd_wpm__text="${spcd_wpm__text}${spcd_wpm__value}
 "
     done
-    eval "spcd_wpm__index=\$((SPCD_STEP_${SPCD_STEP_LEVEL}_INDEX + 1))"
+    spcd_wpm__index=$((SPCD_STEP_1_INDEX + 1))
     for spcd_wpm__root in \
         "${SPCD_PYTHON_PACKAGES}" "${SPCD_PYTHON_VENV_PACKAGES}"; do
         spcd_os_write "${spcd_wpm__root}/env.py" "${spcd_wpm__text}