diff --git a/common/build/build-debian-iso.sh b/common/build/build-debian-iso.sh
new file mode 100644
index 0000000..5565ff8
--- /dev/null
+++ b/common/build/build-debian-iso.sh
@@ -0,0 +1,326 @@
+#!/usr/bin/env bash
+# build-debian-iso.sh — Build all Debian amd64 BD ISOs from jigdo files
+# Source: https://cdimage.debian.org/debian-cd/current/amd64/jigdo-bd/
+#
+# Requirements:
+#   sudo apt install jigdo-file wget
+
+set -euo pipefail
+
+JIGDO_URL="https://cdimage.debian.org/debian-cd/current/amd64/jigdo-bd"
+DEFAULT_MIRROR="https://deb.debian.org/debian"
+OUTPUT_DIR="${OUTPUT_DIR:-./debian-isos}"
+MIRROR="$DEFAULT_MIRROR"
+SCAN_DIR=""
+CACHE_NAME="jigdo-file-cache.db"
+FETCH_BATCH_SIZE="${FETCH_BATCH_SIZE:-30}"
+WGET_ARGS=(
+    --continue
+    --tries=5
+    --retry-connrefused
+    --waitretry=1
+    --timeout=30
+)
+
+die() { echo "ERROR: $*" >&2; exit 1; }
+
+usage() {
+    cat <<EOF
+Usage: $(basename "$0") [OPTIONS]
+
+Build all Debian amd64 BD ISOs from jigdo files without using jigdo-lite.
+
+Options:
+  -o DIR   Output directory  (default: ./debian-isos, or \$OUTPUT_DIR)
+  -m URL   Debian mirror     (default: https://deb.debian.org/debian)
+  -s DIR   Scan DIR for locally cached .deb packages to reuse
+  -h       Show this help
+
+Environment:
+  FETCH_BATCH_SIZE  Number of package URLs fetched per batch (default: 30)
+
+Examples:
+  $(basename "$0")
+  $(basename "$0") -o /data/isos
+  $(basename "$0") -s /var/cache/apt/archives
+  $(basename "$0") -m http://ftp.de.debian.org/debian
+EOF
+}
+
+check_deps() {
+    local missing=()
+    command -v jigdo-file &>/dev/null || missing+=("jigdo-file  (sudo apt install jigdo-file)")
+    command -v wget       &>/dev/null || missing+=("wget        (sudo apt install wget)")
+    command -v gzip       &>/dev/null || missing+=("gzip")
+    command -v grep       &>/dev/null || missing+=("grep")
+    command -v sed        &>/dev/null || missing+=("sed")
+    command -v awk        &>/dev/null || missing+=("awk")
+    (( ${#missing[@]} == 0 )) || { printf 'Missing: %s\n' "${missing[@]}" >&2; exit 1; }
+}
+
+normalize_mirror() {
+    local url="$1"
+    printf '%s/\n' "${url%/}"
+}
+
+fetch_metadata() {
+    local base="$1"
+    local jigdo="${OUTPUT_DIR}/${base}.jigdo"
+    local jigdo_unpacked="${OUTPUT_DIR}/${base}.jigdo.unpacked"
+    local template="${OUTPUT_DIR}/${base}.template"
+
+    [[ -s "$jigdo" ]] || wget -qO "$jigdo" "${JIGDO_URL}/${base}.jigdo"
+    [[ -s "$template" ]] || wget -qO "$template" "${JIGDO_URL}/${base}.template"
+
+    if [[ ! -s "$jigdo_unpacked" || "$jigdo_unpacked" -ot "$jigdo" ]]; then
+        if gzip -cd "$jigdo" >"${jigdo_unpacked}.tmp" 2>/dev/null; then
+            mv "${jigdo_unpacked}.tmp" "$jigdo_unpacked"
+        else
+            cp "$jigdo" "$jigdo_unpacked"
+        fi
+    fi
+}
+
+run_make_image() {
+    local iso="$1"
+    local jigdo="$2"
+    local template="$3"
+    local input_path="$4"
+    local rc=0
+
+    jigdo-file make-image \
+        --image="$iso" \
+        --jigdo="$jigdo" \
+        --template="$template" \
+        --cache="${OUTPUT_DIR}/${CACHE_NAME}" \
+        "$input_path" || rc=$?
+
+    case "$rc" in
+        0|1) return "$rc" ;;
+        2) die "jigdo-file reported a recoverable error while processing '$input_path'" ;;
+        *) die "jigdo-file failed while processing '$input_path' (exit $rc)" ;;
+    esac
+}
+
+write_missing_list() {
+    local iso="$1"
+    local jigdo="$2"
+    local jigdo_unpacked="$3"
+    local template="$4"
+    local list_file="$5"
+    local checksums_file="${list_file}.checksums"
+    local template_source="$template"
+
+    [[ -f "${iso}.tmp" ]] && template_source="${iso}.tmp"
+
+    jigdo-file list-template --template="$template_source" \
+        | awk '$1 ~ /^need-file-/ { print $4 }' >"$checksums_file"
+
+    awk -v mirror="$(normalize_mirror "$MIRROR")" '
+        function trim(s) {
+            sub(/^[[:space:]]+/, "", s)
+            sub(/[[:space:]]+$/, "", s)
+            return s
+        }
+
+        NR == FNR {
+            if ($1 != "") {
+                wanted[$1] = 1
+                wanted_count++
+            }
+            next
+        }
+
+        /^\[/ {
+            section = $0
+            next
+        }
+
+        section != "[Parts]" {
+            next
+        }
+
+        /^[[:space:]]*#/ {
+            next
+        }
+
+        {
+            pos = index($0, "=")
+            if (!pos) {
+                next
+            }
+
+            key = trim(substr($0, 1, pos - 1))
+            if (!(key in wanted)) {
+                next
+            }
+
+            value = trim(substr($0, pos + 1))
+
+            if (value ~ /^[A-Za-z][A-Za-z0-9+.-]*:\/\// || value ~ /^file:/) {
+                print value
+                found[key] = 1
+                found_count++
+                next
+            }
+
+            split(value, parts, ":")
+            label = parts[1]
+            path = substr(value, length(label) + 2)
+
+            if (label == "Debian" || label == "Non-US") {
+                print mirror path
+                found[key] = 1
+                found_count++
+            }
+        }
+
+        END {
+            if (wanted_count != found_count) {
+                for (key in wanted) {
+                    if (!(key in found)) {
+                        printf "Unresolved jigdo part checksum: %s\n", key > "/dev/stderr"
+                    }
+                }
+                exit 2
+            }
+        }
+    ' "$checksums_file" "$jigdo_unpacked" >"$list_file"
+
+    rm -f "$checksums_file"
+}
+
+download_batch() {
+    local list_file="$1"
+    local batch_dir="$2"
+
+    rm -rf "$batch_dir"
+    mkdir -p "$batch_dir"
+
+    wget "${WGET_ARGS[@]}" \
+        --input-file="$list_file" \
+        --force-directories \
+        --directory-prefix="$batch_dir"
+}
+
+build_image() {
+    local base="$1"
+    local iso="${OUTPUT_DIR}/${base}.iso"
+    local jigdo="${OUTPUT_DIR}/${base}.jigdo"
+    local jigdo_unpacked="${OUTPUT_DIR}/${base}.jigdo.unpacked"
+    local template="${OUTPUT_DIR}/${base}.template"
+    local batch_dir="${OUTPUT_DIR}/${base}.download"
+    local list_file="${OUTPUT_DIR}/${base}.missing"
+    local batch_file="${OUTPUT_DIR}/${base}.batch"
+    local fetched_any=0
+
+    echo ""
+    echo "--- $base ---"
+
+    if [[ -f "$iso" ]]; then
+        echo "Already exists, skipping. Delete to rebuild: rm '$iso'"
+        return 0
+    fi
+
+    fetch_metadata "$base"
+
+    if [[ -n "$SCAN_DIR" ]]; then
+        echo "Scanning local packages from: $SCAN_DIR"
+        if run_make_image "$iso" "$jigdo" "$template" "$SCAN_DIR"; then
+            :
+        fi
+        if [[ -f "$iso" ]]; then
+            echo "Done: $iso  ($(du -sh "$iso" | cut -f1))"
+            return 0
+        fi
+    fi
+
+    while true; do
+        write_missing_list "$iso" "$jigdo" "$jigdo_unpacked" "$template" "$list_file"
+        mapfile -t urls < <(grep -v '^$' "$list_file")
+
+        if (( ${#urls[@]} == 0 )); then
+            [[ -f "$iso" ]] && break
+            die "No missing URLs were returned for $base, but the ISO is still incomplete"
+        fi
+
+        echo "Missing files: ${#urls[@]}"
+
+        local offset=0
+        while (( offset < ${#urls[@]} )); do
+            local count=$FETCH_BATCH_SIZE
+            (( offset + count > ${#urls[@]} )) && count=$(( ${#urls[@]} - offset ))
+
+            printf '%s\n' "${urls[@]:offset:count}" >"$batch_file"
+
+            echo "Downloading batch: $((offset + 1))-$((offset + count)) / ${#urls[@]}"
+            download_batch "$batch_file" "$batch_dir"
+            fetched_any=1
+
+            if run_make_image "$iso" "$jigdo" "$template" "$batch_dir"; then
+                :
+            fi
+
+            rm -rf "$batch_dir"
+
+            if [[ -f "$iso" ]]; then
+                break 2
+            fi
+
+            offset=$((offset + count))
+        done
+
+        if (( fetched_any == 0 )); then
+            die "No files were downloaded for $base"
+        fi
+    done
+
+    rm -f "$list_file" "$batch_file"
+    jigdo-file verify --image="$iso" --template="$template" --report=quiet >/dev/null
+    echo "Done: $iso  ($(du -sh "$iso" | cut -f1))"
+}
+
+main() {
+    while [[ $# -gt 0 ]]; do
+        case "$1" in
+            -h|--help)   usage; exit 0 ;;
+            -o|--output) OUTPUT_DIR="$2"; shift 2 ;;
+            -m|--mirror) MIRROR="$2";     shift 2 ;;
+            -s|--scan)   SCAN_DIR="$2";   shift 2 ;;
+            *) die "Unknown option: $1" ;;
+        esac
+    done
+
+    check_deps
+    mkdir -p "$OUTPUT_DIR"
+    [[ -n "$SCAN_DIR" && ! -d "$SCAN_DIR" ]] && die "Scan directory not found: $SCAN_DIR"
+
+    local -a images=()
+    while IFS= read -r name; do
+        images+=("${name%.jigdo}")
+    done < <(
+        wget -qO- "${JIGDO_URL}/" \
+            | grep -oP 'href="debian-[^"]+BD-[0-9]+\.jigdo"' \
+            | grep -oP 'debian-[^"]+\.jigdo' \
+            | grep -v 'debian-edu' \
+            | sort -uV
+    )
+
+    (( ${#images[@]} > 0 )) || die "No BD jigdo files found at $JIGDO_URL"
+
+    echo "Mirror: $(normalize_mirror "$MIRROR")"
+    echo "Output: $OUTPUT_DIR"
+    [[ -n "$SCAN_DIR" ]] && echo "Scan  : $SCAN_DIR"
+    echo "Images: ${images[*]}"
+
+    local failed=0
+    for base in "${images[@]}"; do
+        build_image "$base" || (( ++failed ))
+    done
+
+    echo ""
+    (( failed == 0 )) || die "$failed image(s) failed."
+    echo "All done. ISOs in: $OUTPUT_DIR"
+}
+
+main "$@"