diff --git a/postgres-dump-zstd-docker-sock.sh b/postgres-dump-zstd-docker-sock.sh
index 58a37ed..d30fb8c 100755
--- a/postgres-dump-zstd-docker-sock.sh
+++ b/postgres-dump-zstd-docker-sock.sh
@@ -2,12 +2,23 @@
 set -eu
 
 # PostgreSQL backup triggered through the Docker Engine unix socket.
-# Example: ./postgres-dump-zstd-docker-sock.sh --socket=/var/run/docker.sock --api-version=v1.51 --backup-dir=/backups --container=postgres17 --backup-prefix=pgvector17_all_databases_zstd_
-# Remote example: curl -fsSL https://git.1-h.cc/Scripts/Linux/raw/branch/main/postgres-dump-zstd-docker-sock.sh | sh -s -- --socket=/var/run/docker.sock --api-version=v1.51 --backup-dir=/backups --container=postgres17 --backup-prefix=pgvector17_all_databases_zstd_
+# Example: ./postgres-dump-zstd-docker-sock.sh --container=postgres17 --backup-prefix=pgvector17_all_databases_zstd_ --socket=/var/run/docker.sock --api-version=v1.51 --backup-dir=/backups
+# Remote example: curl -fsSL https://git.1-h.cc/Scripts/Linux/raw/branch/main/postgres-dump-zstd-docker-sock.sh | sh -s -- --container=postgres17 --backup-prefix=pgvector17_all_databases_zstd_ --socket=/var/run/docker.sock --api-version=v1.51 --backup-dir=/backups
 log() {
   printf '%s\n' "[cron] $(date -u '+%Y-%m-%dT%H:%M:%SZ') $*"
 }
 
+log_stream() {
+  log_stream_prefix=$1
+  log_stream_payload=$2
+
+  if [ -n "$log_stream_payload" ]; then
+    printf '%s\n' "$log_stream_payload" | while IFS= read -r log_stream_line; do
+      log "$log_stream_prefix: $log_stream_line"
+    done
+  fi
+}
+
 print_usage() {
   cat <<EOF >&2
 Usage: $0 [--socket=PATH] [--api-version=VERSION] --container=NAME [--backup-dir=DIR] --backup-prefix=PREFIX
@@ -28,12 +39,75 @@ PG_CONTAINER_NAME=""
 BACKUP_DIR="/backups"
 BACKUP_PREFIX=""
 
+require_command() {
+  if ! command -v "$1" >/dev/null 2>&1; then
+    printf '%s requires %s in PATH\n' "$0" "$1" >&2
+    exit 1
+  fi
+}
+
 missing_value() {
   printf 'Missing value for %s\n' "$1" >&2
   print_usage
   exit 1
 }
 
+docker_exec_create() {
+  docker_exec_create_desc=$1
+  docker_exec_create_cmd=$2
+  docker_exec_create_payload=$(jq -n --arg cmd "$docker_exec_create_cmd" '{
+    AttachStdin: false,
+    AttachStdout: true,
+    AttachStderr: true,
+    Tty: true,
+    Cmd: ["bash", "-lc", $cmd]
+  }')
+
+  DOCKER_LAST_RESPONSE=$(curl --fail --silent --show-error --unix-socket "$DOCKER_SOCKET" \
+    -X POST \
+    -H "Content-Type: application/json" \
+    -d "$docker_exec_create_payload" \
+    "$exec_create_endpoint")
+
+  docker_exec_create_id=$(printf '%s' "$DOCKER_LAST_RESPONSE" | jq -r '.Id // empty')
+
+  if [ -z "$docker_exec_create_id" ]; then
+    log "failed to create $docker_exec_create_desc exec for $PG_CONTAINER_NAME"
+    log "docker response: $DOCKER_LAST_RESPONSE"
+    return 1
+  fi
+
+  printf '%s' "$docker_exec_create_id"
+}
+
+docker_exec_start() {
+  docker_exec_start_id=$1
+  docker_exec_start_desc=$2
+  docker_exec_start_endpoint="${docker_api_base}/exec/${docker_exec_start_id}/start"
+  DOCKER_LAST_RESPONSE=$(curl --fail --show-error --silent --unix-socket "$DOCKER_SOCKET" \
+    -X POST \
+    -H "Content-Type: application/json" \
+    -d '{"Detach": false, "Tty": true}' \
+    "$docker_exec_start_endpoint")
+
+  log_stream "$docker_exec_start_desc output" "$DOCKER_LAST_RESPONSE"
+
+  printf '%s' "$DOCKER_LAST_RESPONSE"
+}
+
+docker_exec_exit_code() {
+  docker_exec_exit_id=$1
+  docker_exec_inspect_endpoint="${docker_api_base}/exec/${docker_exec_exit_id}/json"
+  DOCKER_LAST_RESPONSE=$(curl --fail --silent --show-error --unix-socket "$DOCKER_SOCKET" "$docker_exec_inspect_endpoint")
+  docker_exec_exit_code_value=$(printf '%s' "$DOCKER_LAST_RESPONSE" | jq -r '.ExitCode // empty')
+
+  if [ -z "$docker_exec_exit_code_value" ]; then
+    return 1
+  fi
+
+  printf '%s' "$docker_exec_exit_code_value"
+}
+
 while [ "$#" -gt 0 ]; do
   case $1 in
     --socket=*)
@@ -110,6 +184,9 @@ if [ "$#" -gt 0 ]; then
   exit 1
 fi
 
+require_command curl
+require_command jq
+
 if [ -z "$DOCKER_SOCKET" ] || [ -z "$DOCKER_API_VERSION" ] || [ -z "$PG_CONTAINER_NAME" ] || [ -z "$BACKUP_DIR" ] || [ -z "$BACKUP_PREFIX" ]; then
   print_usage
   exit 1
@@ -128,57 +205,26 @@ exec_create_endpoint="${docker_api_base}/containers/${PG_CONTAINER_NAME}/exec"
 log "preparing database backup at $backup_path via docker unix socket"
 
 cmd="set -o pipefail && pg_dumpall --username=\"\${POSTGRES_USER:-postgres}\" --clean | zstd > ${backup_path}"
-create_payload=$(jq -n --arg cmd "$cmd" '{
-  AttachStdin: false,
-  AttachStdout: true,
-  AttachStderr: true,
-  Tty: true,
-  Cmd: ["bash", "-lc", $cmd]
-}')
 
-create_response=$(curl --fail --silent --show-error --unix-socket "$DOCKER_SOCKET" \
-  -X POST \
-  -H "Content-Type: application/json" \
-  -d "$create_payload" \
-  "$exec_create_endpoint")
-
-exec_id=$(printf '%s' "$create_response" | jq -r '.Id // empty')
-
-if [ -z "$exec_id" ]; then
-  log "failed to create exec for $PG_CONTAINER_NAME"
-  log "docker response: $create_response"
+if ! exec_id=$(docker_exec_create "backup" "$cmd"); then
   exit 1
 fi
 
 log "starting exec $exec_id"
 
-exec_start_endpoint="${docker_api_base}/exec/${exec_id}/start"
-start_output=$(curl --fail --show-error --silent --unix-socket "$DOCKER_SOCKET" \
-  -X POST \
-  -H "Content-Type: application/json" \
-  -d '{"Detach": false, "Tty": true}' \
-  "$exec_start_endpoint")
-
-if [ -n "$start_output" ]; then
-  printf '%s\n' "$start_output" | while IFS= read -r line; do
-    log "exec output: $line"
-  done
+if ! start_output=$(docker_exec_start "$exec_id" "exec"); then
+  exit 1
 fi
 
-exec_inspect_endpoint="${docker_api_base}/exec/${exec_id}/json"
-inspect_response=$(curl --fail --silent --show-error --unix-socket "$DOCKER_SOCKET" "$exec_inspect_endpoint")
-
-exit_code=$(printf '%s' "$inspect_response" | jq -r '.ExitCode // empty')
-
-if [ -z "$exit_code" ]; then
+if ! exit_code=$(docker_exec_exit_code "$exec_id"); then
   log "could not determine exec exit code"
-  log "docker inspect response: $inspect_response"
+  log "docker inspect response: $DOCKER_LAST_RESPONSE"
   exit 1
 fi
 
 if [ "$exit_code" != "0" ]; then
   log "backup exec exited with status $exit_code"
-  log "docker inspect response: $inspect_response"
+  log "docker inspect response: $DOCKER_LAST_RESPONSE"
   exit "$exit_code"
 fi
 
@@ -193,25 +239,8 @@ else
   log "backup file not found on host; verifying inside container $PG_CONTAINER_NAME"
 
   verify_cmd="set -eo pipefail && if [ -f \"${backup_path}\" ]; then du -h \"${backup_path}\" 2>/dev/null | awk 'NR==1{print \$1}' || printf 'exists'; else exit 44; fi"
-  verify_payload=$(jq -n --arg cmd "$verify_cmd" '{
-    AttachStdin: false,
-    AttachStdout: true,
-    AttachStderr: true,
-    Tty: true,
-    Cmd: ["bash", "-lc", $cmd]
-  }')
 
-  verify_create_response=$(curl --fail --silent --show-error --unix-socket "$DOCKER_SOCKET" \
-    -X POST \
-    -H "Content-Type: application/json" \
-    -d "$verify_payload" \
-    "$exec_create_endpoint")
-
-  verify_exec_id=$(printf '%s' "$verify_create_response" | jq -r '.Id // empty')
-
-  if [ -z "$verify_exec_id" ]; then
-    log "failed to create verification exec for $PG_CONTAINER_NAME"
-    log "docker response: $verify_create_response"
+  if ! verify_exec_id=$(docker_exec_create "verification" "$verify_cmd"); then
     log "backup command succeeded, but file $backup_path not found"
     log "database backup finished"
     exit 0
@@ -219,27 +248,15 @@ else
 
   log "starting verification exec $verify_exec_id"
 
-  verify_start_endpoint="${docker_api_base}/exec/${verify_exec_id}/start"
-  verify_start_output=$(curl --fail --show-error --silent --unix-socket "$DOCKER_SOCKET" \
-    -X POST \
-    -H "Content-Type: application/json" \
-    -d '{"Detach": false, "Tty": true}' \
-    "$verify_start_endpoint")
-
-  if [ -n "$verify_start_output" ]; then
-    printf '%s\n' "$verify_start_output" | while IFS= read -r line; do
-      log "verify output: $line"
-    done
+  if ! verify_start_output=$(docker_exec_start "$verify_exec_id" "verify"); then
+    log "backup command succeeded, but file $backup_path not confirmed"
+    log "database backup finished"
+    exit 0
   fi
 
-  verify_inspect_endpoint="${docker_api_base}/exec/${verify_exec_id}/json"
-  verify_inspect_response=$(curl --fail --silent --show-error --unix-socket "$DOCKER_SOCKET" "$verify_inspect_endpoint")
-
-  verify_exit_code=$(printf '%s' "$verify_inspect_response" | jq -r '.ExitCode // empty')
-
-  if [ -z "$verify_exit_code" ]; then
+  if ! verify_exit_code=$(docker_exec_exit_code "$verify_exec_id"); then
     log "could not determine verification exec exit code"
-    log "docker inspect response: $verify_inspect_response"
+    log "docker inspect response: $DOCKER_LAST_RESPONSE"
     log "backup command succeeded, but file $backup_path not found"
   elif [ "$verify_exit_code" = "0" ]; then
     verify_size=$(printf '%s' "$verify_start_output" | awk 'NF {last=$0} END {print last}')
@@ -253,7 +270,7 @@ else
     log "backup command succeeded, but file $backup_path not found inside container $PG_CONTAINER_NAME"
   else
     log "verification exec exited with status $verify_exit_code"
-    log "docker inspect response: $verify_inspect_response"
+    log "docker inspect response: $DOCKER_LAST_RESPONSE"
     log "backup command succeeded, but file $backup_path not confirmed"
   fi
 fi