diff --git a/spcd/bootstrap.sh b/spcd/main.sh
similarity index 92%
rename from spcd/bootstrap.sh
rename to spcd/main.sh
index 93709b0..6481aa0 100644
--- a/spcd/bootstrap.sh
+++ b/spcd/main.sh
@@ -1,5 +1,7 @@
 #! /usr/bin/env sh
 
+#╶──────────────────────────────────────╴
+
 # ╭──────────╮
 # │ defaults │
 # ╰──────────╯
@@ -182,7 +184,7 @@ spcd_os_cat() {
     spcd_cat__file="${1}"
     if [ -n "${spcd_cat__file}" ]; then
         spcd_frame_open "${spcd_cat__file}"
-        cat "${spcd_cat__file}"
+        cat "${spcd_cat__file}" || exit
         spcd_frame_shut "${spcd_cat__file}"
     fi
 }
@@ -249,19 +251,6 @@ spcd_git_url() {
     fi
 }
 
-# ╭───────────┬─────────╮
-# │ functions │ openssl │
-# ╰───────────┴─────────╯
-
-spcd_openssl_x509() {
-    spcd_openssl_x509__file="${1}"
-    if [ -f "${spcd_openssl_x509__file}" ]; then
-        openssl x509 \
-            -in "${spcd_openssl_x509__file}" \
-            -noout -text
-    fi
-}
-
 # ╭───────────┬────╮
 # │ functions │ os │
 # ╰───────────┴────╯
@@ -305,7 +294,7 @@ spcd_os_rm() {
     spcd_os_rm__path="${1}"
     if [ -e "${spcd_os_rm__path}" ]; then
         echo "← ${spcd_os_rm__path}"
-        rm -r "${spcd_os_rm__path}"
+        rm -r "${spcd_os_rm__path}" || exit
     fi
 }
 
@@ -342,7 +331,7 @@ spcd_python_ln() {
     if [ -n "${spcd_python_ln__command}" ]; then
         echo "→ ${SPCD_PYTHON_ALIAS} → ${spcd_python_ln__command}"
         ln -f -s "${spcd_python_ln__command}" \
-            "/usr/bin/${SPCD_PYTHON_ALIAS}"
+            "/usr/bin/${SPCD_PYTHON_ALIAS}" || exit
     fi
 }
 
@@ -419,12 +408,12 @@ SPCD_PM_ZYPPER="zypper"
 SPCD_PYTHON_VENV="/opt/venv"
 SPCD_PYTHON_VENV_BINARIES="${SPCD_PYTHON_VENV}/bin"
 
-# ╭───────┬─────────────╮
-# │ steps │ environment │
-# ╰───────┴─────────────╯
+# ╭───────┬─────╮
+# │ steps │ env │
+# ╰───────┴─────╯
 
-spcd_environment_set_variables() {
-    spcd_step "Set variables"
+spcd_set_environment_variables() {
+    spcd_step "Set environment variables"
     # check script first
     [ -n "${SPCD}" ] || spcd_error_ci "SPCD"
     # continuous integration / github → gitea → forgejo
@@ -904,47 +893,18 @@ ${SPCD_PYTHON_VENV}/lib/${SPCD_PYTHON_COMMAND}/site-packages"
     spcd_os_printenv "SPCD_CA" "SPCD_DL"
 }
 
-spcd_environment_list_workspace() {
-    spcd_step "List workspace"
+spcd_list_working_directory() {
+    spcd_step "List working directory"
     spcd_lwd__path="$(realpath .)"
     spcd_os_ls "${spcd_lwd__path}"
 }
 
-# ╭───────┬───────────╮
-# │ steps │ functions │
-# ╰───────┴───────────╯
-
-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
-}
-
 # ╭───────┬─────╮
-# │ steps │ dns │
+# │ steps │ pkg │
 # ╰───────┴─────╯
 
-spcd_dns() {
-    spcd_step "DNS"
-    while true; do
-        spcd_sdr__index=$((spcd_sdr__index + 1))
-        eval "spcd_sdr__value=\"\${SPCD_DNS_${spcd_sdr__index}}\""
-        [ -n "${spcd_sdr__value}" ] || break
-        spcd_sdr__text="${spcd_sdr__text}\
-nameserver ${spcd_sdr__value}
-"
-    done
-    spcd_os_write "${SPCD_DNS_FILE}" "${spcd_sdr__text}"
-}
-
-# ╭───────┬──────────╮
-# │ steps │ packages │
-# ╰───────┴──────────╯
-
-spcd_packages_set_repositories() {
-    spcd_step "Set repositories"
+spcd_set_packages_repositories() {
+    spcd_step "Set packages repositories"
     case "${SPCD_OS_ID}" in
     "${SPCD_OS_ALMA}")
         case "${SPCD_OS_VERSION}" in
@@ -1010,8 +970,8 @@ deb ${SPCD_URL_CHOSEN} ${SPCD_OS_VERSION}-security main universe
     esac
 }
 
-spcd_packages_set_configuration() {
-    spcd_step "Set configuration"
+spcd_set_packages_configuration() {
+    spcd_step "Set packages configuration"
     spcd_os_write "${SPCD_PM_CONF_PATH}" "${SPCD_PM_CONF_TEXT}"
     case "${SPCD_OS_ID}" in
     "${SPCD_OS_ARCH}")
@@ -1024,21 +984,36 @@ spcd_packages_set_configuration() {
     esac
 }
 
-spcd_packages_trust_https() {
-    spcd_step "Trust HTTPS"
+# agnostic steps
+
+spcd_set_https_verification_off() {
     if [ -n "${SPCD_CA}" ] || [ "${SPCD_PM}" = "${SPCD_PM_APT}" ]; then
+        spcd_step "Set HTTPS verification off"
         spcd_os_mkdir "$(dirname "${SPCD_PM_HTTPS_PATH}")"
         spcd_os_write "${SPCD_PM_HTTPS_PATH}" "${SPCD_PM_HTTPS_TEXT}"
     fi
 }
 
-spcd_packages_update_catalog() {
-    spcd_step "Update catalog"
-    ${SPCD_PM_UPDATE}
+spcd_set_dns_resolving() {
+    spcd_step "Set DNS resolving"
+    while true; do
+        spcd_sdr__index=$((spcd_sdr__index + 1))
+        eval "spcd_sdr__value=\"\${SPCD_DNS_${spcd_sdr__index}}\""
+        [ -n "${spcd_sdr__value}" ] || break
+        spcd_sdr__text="${spcd_sdr__text}\
+nameserver ${spcd_sdr__value}
+"
+    done
+    spcd_os_write "${SPCD_DNS_FILE}" "${spcd_sdr__text}"
 }
 
-spcd_packages_install_tools() {
-    spcd_step "Install tools"
+spcd_update_packages_catalog() {
+    spcd_step "Update packages catalog"
+    ${SPCD_PM_UPDATE} || exit
+}
+
+spcd_install_packages_tools() {
+    spcd_step "Install packages tools"
     spcd_install_package "${SPCD_PKG_PKG}"
 }
 
@@ -1061,35 +1036,35 @@ spcd_write_ca_certificates() {
         spcd_wcc__path="${SPCD_CA_ROOT}/${spcd_wcc__index}.crt"
         spcd_split
         spcd_os_write "${spcd_wcc__path}" "${spcd_wcc__text}"
-        spcd_openssl_x509 "${spcd_wcc__path}"
+        spcd_openssl "${spcd_wcc__path}"
     done
 }
 
 spcd_update_ca_certificates() {
     spcd_step "Update CA certificates"
-    ${SPCD_CMD_CA}
+    ${SPCD_CMD_CA} || exit
 }
 
-# ╭───────┬──────────╮
-# │ steps │ packages │
-# ╰───────┴──────────╯
+# ╭───────┬─────╮
+# │ steps │ pkg │
+# ╰───────┴─────╯
 
-spcd_packages_verify_https() {
-    spcd_step "Verify HTTPS"
+spcd_set_https_verification_on() {
+    spcd_step "Set HTTPS verification on"
     spcd_os_rm "${SPCD_PM_HTTPS_PATH}"
 }
 
-spcd_packages_upgrade_system() {
-    spcd_step "Upgrade system"
-    ${SPCD_PM_UPGRADE}
+spcd_upgrade_packages() {
+    spcd_step "Upgrade packages"
+    ${SPCD_PM_UPGRADE} || exit
 }
 
-spcd_packages_install_dos2unix() {
+spcd_install_dos2unix() {
     spcd_step "Install dos2unix"
     spcd_install_package "${SPCD_PKG_DOS2UNIX}"
 }
 
-spcd_packages_install_git() {
+spcd_install_git() {
     spcd_step "Install Git"
     spcd_install_package "${SPCD_PKG_GIT}"
 }
@@ -1098,8 +1073,8 @@ spcd_packages_install_git() {
 # │ steps │ python │
 # ╰───────┴────────╯
 
-spcd_python_install() {
-    spcd_step "Install package"
+spcd_install_python() {
+    spcd_step_in "Install Python"
     spcd_install_package "${SPCD_PYTHON_PACKAGE}"
     spcd_step "Link alias to command"
     spcd_python_ln "${SPCD_PYTHON_COMMAND}"
@@ -1123,10 +1098,11 @@ index-url = ${SPCD_URL_PYTHON}
     export PATH="${SPCD_PYTHON_VENV_BINARIES}:${PATH}"
     export VIRTUAL_ENV="${SPCD_PYTHON_VENV}"
     spcd_step_out
+    spcd_step_out
 }
 
-spcd_python_modules() {
-    spcd_step_in "Modules"
+spcd_install_python_modules() {
+    spcd_step_in "Python modules"
     spcd_ipm__target="${SPCD_PYTHON_VENV_PACKAGES}"
     spcd_step "List"
     spcd_os_ls "${spcd_ipm__target}"
@@ -1134,7 +1110,7 @@ spcd_python_modules() {
     spcd_ipm__path="$(spcd_python_pip "${SPCD_GIT_MAIN}")"
     # check matching of file and variable
     spcd_step "Check"
-    spcd_ipm__script="${spcd_ipm__path}/bootstrap.sh"
+    spcd_ipm__script="${spcd_ipm__path}/main.sh"
     ls -l "${spcd_ipm__script}"
     spcd_ipm__check="${spcd_ipm__script}.${SPCD_CMD_SUM}"
     "${SPCD_CMD_SUM}" "${spcd_ipm__script}" >"${spcd_ipm__check}"
@@ -1213,8 +1189,8 @@ spcd_install_packages() {
     spcd_step_out
 }
 
-spcd_python_write_module() {
-    spcd_step "Write module"
+spcd_write_python_module() {
+    spcd_step "Write Python module"
     for spcd_wpm__variable in \
         OS_ID OS_VERSION \
         PROJECT_ROOT PROJECT_PATH PROJECT_NAME \
@@ -1232,8 +1208,8 @@ SPCD_STEP = $((SPCD_STEP + 1))
     done
 }
 
-spcd_python_switch() {
-    spcd_step "Switch"
+spcd_switch_to_python() {
+    spcd_step "Switch to Python"
     spcd_stp__name="$(basename "${SPCD_GIT_MAIN}")"
     echo "\
 ${SPCD_PATH}
@@ -1244,45 +1220,62 @@ ${SPCD_PYTHON_ALIAS} / ${spcd_stp__name}"
 
 #╶──────────────────────────────────────╴
 
+# ╭───────────╮
+# │ functions │
+# ╰───────────╯
+
+spcd_install_package() {
+    spcd_install_package__name="${1}"
+    if [ -n "${spcd_install_package__name}" ]; then
+        ${SPCD_PM_INSTALL} "${spcd_install_package__name}" || exit
+        ${SPCD_PM_CLEAN} || exit
+    fi
+}
+
+spcd_openssl() {
+    spcd_openssl__file="${1}"
+    if [ -f "${spcd_openssl__file}" ]; then
+        openssl x509 \
+            -in "${spcd_openssl__file}" \
+            -noout -text ||
+            exit
+    fi
+}
+
+#╶──────────────────────────────────────╴
+
 # ╭──────╮
 # │ main │
 # ╰──────╯
 
 spcd_main() {
-    # environment
-    spcd_step_in "Environment"
-    spcd_environment_set_variables
-    spcd_environment_list_workspace
-    spcd_step_out
-    # dns
-    spcd_dns
-    # packages
-    spcd_step_in "Packages"
-    spcd_packages_set_repositories
-    spcd_packages_set_configuration
-    spcd_packages_trust_https
-    spcd_packages_update_catalog
-    spcd_packages_install_tools
-    spcd_step_out
+    # env
+    spcd_set_environment_variables
+    spcd_list_working_directory
+    # pkg
+    spcd_set_packages_repositories
+    spcd_set_packages_configuration
+    #
+    spcd_set_https_verification_off
+    spcd_set_dns_resolving
+    spcd_update_packages_catalog
+    spcd_install_packages_tools
     # ca
     spcd_install_ca_certificates
     spcd_write_ca_certificates
     spcd_update_ca_certificates
-    # packages
-    spcd_step_in "Packages"
-    spcd_packages_verify_https
-    spcd_packages_update_catalog
-    spcd_packages_upgrade_system
-    spcd_packages_install_dos2unix
-    spcd_packages_install_git
-    spcd_step_out
+    # pkg
+    spcd_set_https_verification_on
+    spcd_update_packages_catalog
+    spcd_upgrade_packages
+    spcd_install_dos2unix
+    spcd_install_git
     # python
-    spcd_step_in "Python"
-    spcd_python_install
-    spcd_python_modules
+    spcd_install_python
+    spcd_install_python_modules
     spcd_install_packages
-    spcd_python_write_module
-    spcd_python_switch
+    spcd_write_python_module
+    spcd_switch_to_python
 }
 
 spcd_main