diff --git a/Caddyfile b/Caddyfile
index f7d9564b..1dda17ff 100644
--- a/Caddyfile
+++ b/Caddyfile
@@ -2,18 +2,24 @@
 #
 # - gendsgn.ru — main production site, auto-TLS via Let's Encrypt.
 # - www.gendsgn.ru — 301 redirect to apex (canonical URL).
-# - :80 — fallback for raw IP access. Will be removed once everyone uses the domain.
+# - :80 — fallback for raw IP access. Closed by same auth gate (pilot phase).
 #
 # `handle /api/*` (NOT `handle_path`) — we keep the /api prefix because
 # the FastAPI router is mounted at /api/v1/*.
+#
+# Auth gate: basic_auth for pilot phase (2026-05-23).
+# Users managed via caddy/users.caddy.snippet (git history = audit trail).
+# Public exclusions: /health (liveness probe), /preview/* (static mockups).
 
 gendsgn.ru {
     encode zstd gzip
 
-    handle /api/* {
-        reverse_proxy backend:8000
+    log {
+        output file /var/log/caddy/gendsgn.ru.log
+        format json
     }
 
+    # Liveness probe — public, before auth (GHA deploy smoke check).
     handle /health {
         reverse_proxy backend:8000
     }
@@ -25,6 +31,9 @@ gendsgn.ru {
         file_server browse
     }
 
+    # Auth gate (applies to all routes not matched above).
+    import caddy/users.caddy.snippet
+
     # Trade-In MVP subproject (tradein-mvp/) — gendesign-tradein docker stack,
     # подключен через gendesign_shared network. Routes ДО универсального handle
     # потому что Caddy матчит handle-блоки сверху вниз.
@@ -45,6 +54,10 @@ gendsgn.ru {
         reverse_proxy tradein-frontend:3000
     }
 
+    handle /api/* {
+        reverse_proxy backend:8000
+    }
+
     handle {
         reverse_proxy frontend:3000
     }
@@ -99,16 +112,19 @@ git.gendsgn.ru {
     }
 }
 
-# Plain HTTP by IP — kept for ssh-tunnel / debugging.
-# Caddy issues no TLS here (no hostname).
+# Plain HTTP by IP — closed by same auth gate (prevent bypass via direct IP / SSH tunnel).
+# Caddy issues no TLS here (no hostname). /health remains public.
 :80 {
     encode zstd gzip
 
-    handle /api/* {
+    handle /health {
         reverse_proxy backend:8000
     }
 
-    handle /health {
+    # Auth gate (same snippet as gendsgn.ru).
+    import caddy/users.caddy.snippet
+
+    handle /api/* {
         reverse_proxy backend:8000
     }
 
diff --git a/caddy/users.caddy.snippet b/caddy/users.caddy.snippet
new file mode 100644
index 00000000..9b37ebb7
--- /dev/null
+++ b/caddy/users.caddy.snippet
@@ -0,0 +1,22 @@
+# GenDesign Pilot — basic_auth users gate
+# Last updated: 2026-05-23
+# Add/remove via scripts/auth/add_user.sh / remove_user.sh, then PR.
+#
+# Format: username  bcrypt_hash_base64  # comment
+# Hash generation: caddy hash-password --plaintext <pass> | tr -d '\n' | base64 -w 0
+# Caddy 2.11+ requires base64-encoded bcrypt hashes in Caddyfile basic_auth.
+# Realm is set as argument to basic_auth, not as subdirective.
+
+basic_auth bcrypt "GenDesign Pilot" {
+    admin  JDJhJDE0JHVXRGpmWFBMMmNZd1duQUFJVWFkRi5RVy4xbHBVL3BPaTF6dFBvbUJ5enZvaXQ3bnZ0eGU2  # internal master (qa-tester + health checks, 2026-05-23)
+    user1  JDJhJDE0JGVHLi5XYUtnUnI5TTUweDBYNGpxQXV5OTNtWFlkYkZQRzJXVzlhSWxRMnhFN25vVDhleE11  # TBD (2026-05-23)
+    user2  JDJhJDE0JHl1Vk1HL1ZJQlY5R0FJQndtSzRBcU8wQ0kxUjdicXpHRldBR2JLQmkvUlJ6aWp0Z0EvMjYu  # TBD (2026-05-23)
+    user3  JDJhJDE0JGFOeEwwdnFaUjZiWWpkckVkWFdvT2VMVTkubWZrMVBtQlNmcmg4ZS9qU01OYndPVXRzT1Iy  # TBD (2026-05-23)
+    user4  JDJhJDE0JDJWbkY0YWNIRGhCMlFGekhFM2tVSHVxY0JEWm9UOVNqRTBMbGYzbERHcE5sQjF3Znd6QkNh  # TBD (2026-05-23)
+    user5  JDJhJDE0JDAzTEhkd25STjdUTUtUQkdaREdkSU9mdmlVWEI0d1NxTTRkQnhydklDLk5kT3c2MGdOZnA2  # TBD (2026-05-23)
+    user6  JDJhJDE0JC9vZnZaUU5TVkNUNnRiU3F3QjhYTXVCb2xaSWlzb3U5aUVtY29jSlRyMExOVGdpOHhYc3ky  # TBD (2026-05-23)
+    user7  JDJhJDE0JFlFSDJRV1hsb0kyUmYuMjdMd1FuTHVObC9yQUNNQy9WRGZWMnlUc2wuRUFDOEV6SEJrbkou  # TBD (2026-05-23)
+    user8  JDJhJDE0JFd0alo2VmZYWDlCcHFqellTWC9RSi44WVhQUi5hVFk5djd4emlwcWVvMDExcEU1MVpDL1Yu  # TBD (2026-05-23)
+    user9  JDJhJDE0JHRPZzVEd2ZKaldUWXFSUzI5c3RHTE9NVnp1amRFVkVMTHRFMGF2eUgzbzk2SEJvekdLQ3ZT  # TBD (2026-05-23)
+    user10 JDJhJDE0JEo1QVRUTk1wejgucUI1ZFAzTEE0WWVxQk55c29hTGlHZ243RVhUc2F1aldIc0pSSHVIOUxL  # TBD (2026-05-23)
+}
diff --git a/docker-compose.prod.yml b/docker-compose.prod.yml
index 7434fe4c..37506d2d 100644
--- a/docker-compose.prod.yml
+++ b/docker-compose.prod.yml
@@ -185,9 +185,11 @@ services:
       - "443:443"
     volumes:
       - ./Caddyfile:/etc/caddy/Caddyfile:ro
+      - ./caddy/users.caddy.snippet:/etc/caddy/caddy/users.caddy.snippet:ro
       - ./preview:/srv/preview:ro
       - caddy_data:/data
       - caddy_config:/config
+      - caddy_logs:/var/log/caddy
     # backend: service_healthy — backend имеет /health endpoint, готов до Caddy.
     # frontend: service_started — НЕ service_healthy: даже если frontend healthcheck
     # дребезжит, Caddy всё равно стартует (можно отдавать 502 для /, но
@@ -209,6 +211,7 @@ volumes:
   redis_data:
   caddy_data:
   caddy_config:
+  caddy_logs:
 
 networks:
   # Внешняя сеть, создаётся вне compose (см. docs/obsidian-livesync.md).
diff --git a/docs/PILOT_ACCESS.md b/docs/PILOT_ACCESS.md
new file mode 100644
index 00000000..ef8e9b1c
--- /dev/null
+++ b/docs/PILOT_ACCESS.md
@@ -0,0 +1,11 @@
+# Доступ к GenDesign Pilot
+
+**URL**: https://gendsgn.ru/
+**Логин**: {USERNAME}
+**Пароль**: {PASSWORD}
+
+При первом заходе браузер запросит данные — введите выше.
+Credentials кэшируются до закрытия окна браузера.
+
+Если забыли пароль — напишите claudestars@proton.me, мы выпустим новый.
+По завершении пилота доступ будет отозван.
diff --git a/docs/runbooks/basic_auth_management.md b/docs/runbooks/basic_auth_management.md
new file mode 100644
index 00000000..718a1de2
--- /dev/null
+++ b/docs/runbooks/basic_auth_management.md
@@ -0,0 +1,64 @@
+# Caddy basic_auth — управление пользователями
+
+Snippet: `caddy/users.caddy.snippet`
+Scripts: `scripts/auth/{add,remove,list}_user.sh`
+Git history = audit trail для всех изменений пользователей.
+
+## Добавить юзера
+
+1. `./scripts/auth/add_user.sh <username> "<comment>"`
+2. Скрипт сгенерит 16-char password, забери его в безопасное место
+3. Commit `caddy/users.caddy.snippet` → PR → merge → GHA deploy → Caddy reload
+4. Выдай username/password стейкхолдеру через защищённый канал (Telegram secret chat / Signal)
+
+Шаблон письма: `docs/PILOT_ACCESS.md`
+
+## Удалить юзера
+
+1. `./scripts/auth/remove_user.sh <username>`
+2. Commit → PR → merge → deploy
+
+Caddy начнёт отклонять запросы этого юзера сразу после reload (через ~1 мин после merge).
+
+## Сменить пароль юзеру
+
+1. `./scripts/auth/remove_user.sh <username>` + `./scripts/auth/add_user.sh <username> "<comment>"` в одном PR
+
+## Посмотреть текущих юзеров
+
+```bash
+./scripts/auth/list_users.sh
+```
+
+## В случае утечки credentials
+
+1. `./scripts/auth/remove_user.sh <affected_username>` СРАЗУ
+2. Force-commit + push → merge ASAP (reviewer быстрее через personal DM)
+3. Caddy reload проверить вручную: `docker compose -f docker-compose.prod.yml exec caddy caddy reload --config /etc/caddy/Caddyfile`
+4. Уведомить остальных стейкхолдеров
+
+## Аудит логи
+
+- Access log: `/var/log/caddy/gendsgn.ru.log` (все запросы, JSON)
+- Auth audit: `/var/log/caddy/auth_audit.log` (authentication events, JSON)
+
+```bash
+# Просмотр auth событий в реальном времени
+docker compose -f docker-compose.prod.yml exec caddy tail -f /var/log/caddy/auth_audit.log | jq
+
+# Посмотреть кто логинился сегодня
+docker compose -f docker-compose.prod.yml exec caddy grep "$(date +%Y-%m-%d)" /var/log/caddy/auth_audit.log | jq '.user_id'
+```
+
+## Caddy reload после ручной правки на VPS
+
+```bash
+# Если snippet изменён вручную на VPS (минуя GHA):
+docker compose -f docker-compose.prod.yml exec caddy caddy reload --config /etc/caddy/Caddyfile
+```
+
+Стандартный путь (через PR + GHA deploy) делает reload автоматически.
+
+## Phase 2 (TODO)
+
+GlitchTip forwarder sidecar — отдельный PR. Будет парсить `auth_audit.log` и отправлять события в GlitchTip для dashboard + alerting при brute-force.
diff --git a/scripts/auth/add_user.sh b/scripts/auth/add_user.sh
new file mode 100644
index 00000000..b0584a5f
--- /dev/null
+++ b/scripts/auth/add_user.sh
@@ -0,0 +1,98 @@
+#!/usr/bin/env bash
+# add_user.sh — добавить пользователя в caddy/users.caddy.snippet
+# Usage: ./scripts/auth/add_user.sh <username> "<comment>"
+#
+# - Читает пароль из stdin (pipe) или генерирует 16-char random если интерактивен.
+# - Bcrypt через `docker run --rm caddy:2 caddy hash-password`.
+# - Печатает plain password на stdout ОДИН РАЗ.
+# - НЕ коммитит изменения — это задача разработчика.
+set -euo pipefail
+
+SNIPPET="$(dirname "$(dirname "$(realpath "$0")")")/caddy/users.caddy.snippet"
+
+usage() {
+    echo "Usage: $0 <username> \"<comment>\"" >&2
+    exit 1
+}
+
+# ─── args ────────────────────────────────────────────────────────────────────
+
+[[ $# -lt 2 ]] && usage
+
+USERNAME="$1"
+COMMENT="$2"
+DATE="$(date -u +%Y-%m-%d)"
+
+# Validate username: ^[a-z][a-z0-9-]{2,30}$
+if ! [[ "$USERNAME" =~ ^[a-z][a-z0-9-]{2,30}$ ]]; then
+    echo "ERROR: invalid username '$USERNAME'. Must match ^[a-z][a-z0-9-]{2,30}$" >&2
+    exit 1
+fi
+
+# ─── idempotency guard ────────────────────────────────────────────────────────
+
+if grep -qP "^\s+${USERNAME}\s" "$SNIPPET" 2>/dev/null; then
+    echo "ERROR: user '$USERNAME' already exists in $SNIPPET. Remove first with remove_user.sh." >&2
+    exit 1
+fi
+
+# ─── password ─────────────────────────────────────────────────────────────────
+
+if [ -t 0 ]; then
+    # Interactive — generate random password
+    PLAIN_PASS="$(LC_ALL=C tr -dc 'A-Za-z0-9' </dev/urandom | head -c 16)"
+else
+    # Piped input
+    read -r PLAIN_PASS
+fi
+
+if [[ -z "$PLAIN_PASS" ]]; then
+    echo "ERROR: empty password" >&2
+    exit 1
+fi
+
+# ─── bcrypt via caddy container ───────────────────────────────────────────────
+# Caddy 2.11+ requires base64-encoded bcrypt in Caddyfile basic_auth.
+# Password passed via stdin to avoid exposure in process list.
+
+HASH="$(printf '%s' "$PLAIN_PASS" | docker run --rm -i caddy:2 sh -c 'read -r p; caddy hash-password --plaintext "$p" | tr -d "\n" | base64 -w 0')"
+
+if [[ -z "$HASH" ]]; then
+    echo "ERROR: caddy hash-password returned empty hash" >&2
+    exit 1
+fi
+
+# ─── insert into snippet ─────────────────────────────────────────────────────
+# Insert before the closing brace of basic_auth block
+
+if ! grep -q '^}' "$SNIPPET"; then
+    echo "ERROR: cannot find closing brace in $SNIPPET" >&2
+    exit 1
+fi
+
+# Use a temp file for safe in-place edit
+TMP="$(mktemp)"
+trap 'rm -f "$TMP"' EXIT
+
+# Insert new user line before the last closing `}` of the basic_auth block
+awk -v user="$USERNAME" -v hash="$HASH" -v comment="$COMMENT" -v date="$DATE" '
+/^}/ && !done {
+    printf "    %-7s %s  # %s (%s)\n", user, hash, comment, date
+    done=1
+}
+{ print }
+' "$SNIPPET" > "$TMP"
+
+mv "$TMP" "$SNIPPET"
+
+# ─── output ───────────────────────────────────────────────────────────────────
+
+echo "Added user '$USERNAME' to $SNIPPET"
+echo ""
+echo "Plain password (save now — not stored anywhere):"
+echo "$PLAIN_PASS"
+echo ""
+echo "Next steps:"
+echo "  1. Commit caddy/users.caddy.snippet → PR → merge → GHA deploy"
+echo "  2. After deploy, Caddy auto-reloads (deploy.yml does caddy reload)"
+echo "  3. Send username + password to stakeholder via secure channel"
diff --git a/scripts/auth/list_users.sh b/scripts/auth/list_users.sh
new file mode 100644
index 00000000..102d9f1b
--- /dev/null
+++ b/scripts/auth/list_users.sh
@@ -0,0 +1,28 @@
+#!/usr/bin/env bash
+# list_users.sh — показать текущих пользователей (имена + comment, без хешей)
+# Usage: ./scripts/auth/list_users.sh
+set -euo pipefail
+
+SNIPPET="$(dirname "$(dirname "$(realpath "$0")")")/caddy/users.caddy.snippet"
+
+if [[ ! -f "$SNIPPET" ]]; then
+    echo "ERROR: snippet not found at $SNIPPET" >&2
+    exit 1
+fi
+
+echo "Users in $SNIPPET:"
+echo ""
+printf "%-12s %s\n" "USERNAME" "COMMENT"
+printf "%-12s %s\n" "--------" "-------"
+
+# Extract lines that look like user entries (indented username + base64 hash + optional comment)
+# Format: <spaces> username  <base64_hash>  # comment
+grep -P '^\s+[a-z][a-z0-9-]+\s+[A-Za-z0-9+/]+=*' "$SNIPPET" | \
+    sed -E 's/^\s+([a-z][a-z0-9-]+)\s+\S+\s*(#\s*)?(.*)$/\1\t\3/' | \
+    while IFS=$'\t' read -r user comment; do
+        printf "%-12s %s\n" "$user" "$comment"
+    done
+
+echo ""
+TOTAL=$(grep -cP '^\s+[a-z][a-z0-9-]+\s+[A-Za-z0-9+/]+=*' "$SNIPPET" || true)
+echo "Total: $TOTAL user(s)"
diff --git a/scripts/auth/remove_user.sh b/scripts/auth/remove_user.sh
new file mode 100644
index 00000000..8787a5aa
--- /dev/null
+++ b/scripts/auth/remove_user.sh
@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+# remove_user.sh — удалить пользователя из caddy/users.caddy.snippet
+# Usage: ./scripts/auth/remove_user.sh <username>
+#
+# НЕ коммитит изменения — это задача разработчика.
+set -euo pipefail
+
+SNIPPET="$(dirname "$(dirname "$(realpath "$0")")")/caddy/users.caddy.snippet"
+
+usage() {
+    echo "Usage: $0 <username>" >&2
+    exit 1
+}
+
+[[ $# -lt 1 ]] && usage
+
+USERNAME="$1"
+
+# Validate username format
+if ! [[ "$USERNAME" =~ ^[a-z][a-z0-9-]{2,30}$ ]]; then
+    echo "ERROR: invalid username '$USERNAME'. Must match ^[a-z][a-z0-9-]{2,30}$" >&2
+    exit 1
+fi
+
+# Check user exists
+if ! grep -qP "^\s+${USERNAME}\s" "$SNIPPET" 2>/dev/null; then
+    echo "ERROR: user '$USERNAME' not found in $SNIPPET" >&2
+    exit 1
+fi
+
+# Remove the line with this username (safe in-place via temp file)
+TMP="$(mktemp)"
+trap 'rm -f "$TMP"' EXIT
+
+grep -vP "^\s+${USERNAME}\s" "$SNIPPET" > "$TMP"
+mv "$TMP" "$SNIPPET"
+
+echo "Removed user '$USERNAME' from $SNIPPET"
+echo ""
+echo "Next steps:"
+echo "  1. Commit caddy/users.caddy.snippet → PR → merge → GHA deploy"
+echo "  2. After deploy, Caddy auto-reloads — user access revoked"