diff --git a/.env.example b/.env.example
index e2300a0..dd809b5 100644
--- a/.env.example
+++ b/.env.example
@@ -1,8 +1,22 @@
 
 # API CONFIGURATION
 # URL where the API can be accessed by the browser
-# Default: http://localhost:5055 (works for most Docker setups)
-# Change this if you're running on a different host/port (e.g., http://your-server-ip:5055)
+# This setting allows the frontend to connect to the API at runtime (no rebuild needed!)
+#
+# IMPORTANT: Do NOT include /api at the end - it will be added automatically!
+#
+# Common scenarios:
+# - Docker on localhost: http://localhost:5055 (default, works for most cases)
+# - Docker on LAN/remote server: http://192.168.1.100:5055 or http://your-server-ip:5055
+# - Behind reverse proxy with custom domain: https://your-domain.com
+# - Behind reverse proxy with subdomain: https://api.your-domain.com
+#
+# Examples for reverse proxy users:
+# - API_URL=https://notebook.example.com  (frontend will call https://notebook.example.com/api/*)
+# - API_URL=https://api.example.com       (frontend will call https://api.example.com/api/*)
+#
+# Note: If not set, the system will auto-detect based on the incoming request.
+# Only set this if you need to override the auto-detection (e.g., reverse proxy scenarios).
 API_URL=http://localhost:5055
 
 # SECURITY
diff --git a/Dockerfile b/Dockerfile
index 047f248..2f59089 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -84,7 +84,14 @@ COPY supervisord.conf /etc/supervisor/conf.d/supervisord.conf
 # Create log directories
 RUN mkdir -p /var/log/supervisor
 
-# No default API_URL - the API will auto-detect from incoming requests
-# Users can still override by setting API_URL environment variable if needed
+# Runtime API URL Configuration
+# The API_URL environment variable can be set at container runtime to configure
+# where the frontend should connect to the API. This allows the same Docker image
+# to work in different deployment scenarios without rebuilding.
+#
+# If not set, the system will auto-detect based on incoming requests.
+# Set API_URL when using reverse proxies or custom domains.
+#
+# Example: docker run -e API_URL=https://your-domain.com/api ...
 
 CMD ["/usr/bin/supervisord", "-c", "/etc/supervisor/conf.d/supervisord.conf"]
diff --git a/Dockerfile.single b/Dockerfile.single
index c78c605..b99e7d4 100644
--- a/Dockerfile.single
+++ b/Dockerfile.single
@@ -88,7 +88,14 @@ COPY supervisord.single.conf /etc/supervisor/conf.d/supervisord.conf
 # Create log directories
 RUN mkdir -p /var/log/supervisor
 
-# No default API_URL - the API will auto-detect from incoming requests
-# Users can still override by setting API_URL environment variable if needed
+# Runtime API URL Configuration
+# The API_URL environment variable can be set at container runtime to configure
+# where the frontend should connect to the API. This allows the same Docker image
+# to work in different deployment scenarios without rebuilding.
+#
+# If not set, the system will auto-detect based on incoming requests.
+# Set API_URL when using reverse proxies or custom domains.
+#
+# Example: docker run -e API_URL=https://your-domain.com/api ...
 
 CMD ["/usr/bin/supervisord", "-c", "/etc/supervisor/conf.d/supervisord.conf"]
\ No newline at end of file
diff --git a/docs/deployment/index.md b/docs/deployment/index.md
index 45055cd..60506c4 100644
--- a/docs/deployment/index.md
+++ b/docs/deployment/index.md
@@ -29,7 +29,14 @@ This section provides comprehensive guides for deploying Open Notebook in differ
 - Development tools and debugging
 - Contributing to the project
 
-### 4. [Security Configuration](security.md)
+### 4. [Reverse Proxy Configuration](reverse-proxy.md)
+**For production deployments with custom domains**
+- nginx, Caddy, Traefik configurations
+- Custom domain setup
+- SSL/HTTPS configuration
+- Runtime API URL configuration
+
+### 5. [Security Configuration](security.md)
 **Essential for public deployments**
 - Password protection setup
 - Security best practices
@@ -50,6 +57,12 @@ This section provides comprehensive guides for deploying Open Notebook in differ
 - You have resource constraints
 - You don't need to scale services independently
 
+### Use Reverse Proxy Setup if:
+- You're deploying with a custom domain
+- You need HTTPS/SSL encryption
+- You're using nginx, Caddy, or Traefik
+- You want to expose only specific ports publicly
+
 ### Use Development Setup if:
 - You want to contribute to the project
 - You need to modify the source code
diff --git a/docs/deployment/reverse-proxy.md b/docs/deployment/reverse-proxy.md
new file mode 100644
index 0000000..92faa76
--- /dev/null
+++ b/docs/deployment/reverse-proxy.md
@@ -0,0 +1,304 @@
+# Reverse Proxy Configuration
+
+This guide helps you deploy Open Notebook behind a reverse proxy (nginx, Caddy, Traefik, etc.) or with a custom domain.
+
+## The API_URL Environment Variable
+
+Starting with v1.0+, Open Notebook supports runtime configuration of the API URL through the `API_URL` environment variable. This means you can use the same Docker image in different deployment scenarios without rebuilding.
+
+### How It Works
+
+The frontend uses a three-tier priority system to determine the API URL:
+
+1. **Runtime Configuration** (Highest Priority): `API_URL` environment variable set at container runtime
+2. **Build-time Configuration**: `NEXT_PUBLIC_API_URL` baked into the Docker image
+3. **Auto-detection** (Fallback): Infers from the incoming HTTP request
+
+## Common Scenarios
+
+### Scenario 1: Docker on Localhost (Default)
+
+No configuration needed! The system auto-detects.
+
+```bash
+docker run -d \
+  --name open-notebook \
+  -p 8502:8502 -p 5055:5055 \
+  -v ./notebook_data:/app/data \
+  -v ./surreal_data:/mydata \
+  lfnovo/open_notebook:v1-latest-single
+```
+
+### Scenario 2: Docker on Remote Server (LAN/VPS)
+
+Access via IP address - auto-detection works, but you can be explicit:
+
+```bash
+docker run -d \
+  --name open-notebook \
+  -p 8502:8502 -p 5055:5055 \
+  -e API_URL=http://192.168.1.100:5055 \
+  -v ./notebook_data:/app/data \
+  -v ./surreal_data:/mydata \
+  lfnovo/open_notebook:v1-latest-single
+```
+
+> **Note**: Don't include `/api` at the end - the system adds this automatically!
+
+### Scenario 3: Behind Reverse Proxy with Custom Domain
+
+This is where `API_URL` is **essential**. Your reverse proxy handles HTTPS and routing.
+
+> **Important**: If your reverse proxy forwards `/api` requests to the backend, set `API_URL` to just the domain (without `/api` suffix). The frontend will append `/api` automatically.
+
+#### Example: nginx + Docker Compose
+
+**docker-compose.yml:**
+```yaml
+version: '3.8'
+
+services:
+  open-notebook:
+    image: lfnovo/open_notebook:v1-latest-single
+    container_name: open-notebook
+    environment:
+      - API_URL=https://notebook.example.com
+      - OPENAI_API_KEY=${OPENAI_API_KEY}
+    volumes:
+      - ./notebook_data:/app/data
+      - ./surreal_data:/mydata
+    ports:
+      - "8502:8502"  # Frontend
+      - "5055:5055"  # API
+    restart: unless-stopped
+
+  nginx:
+    image: nginx:alpine
+    container_name: nginx-proxy
+    ports:
+      - "80:80"
+      - "443:443"
+    volumes:
+      - ./nginx.conf:/etc/nginx/nginx.conf:ro
+      - ./ssl:/etc/nginx/ssl:ro
+    depends_on:
+      - open-notebook
+    restart: unless-stopped
+```
+
+**nginx.conf:**
+```nginx
+http {
+    upstream frontend {
+        server open-notebook:8502;
+    }
+
+    upstream api {
+        server open-notebook:5055;
+    }
+
+    server {
+        listen 80;
+        server_name notebook.example.com;
+        return 301 https://$server_name$request_uri;
+    }
+
+    server {
+        listen 443 ssl http2;
+        server_name notebook.example.com;
+
+        ssl_certificate /etc/nginx/ssl/fullchain.pem;
+        ssl_certificate_key /etc/nginx/ssl/privkey.pem;
+
+        # Frontend
+        location / {
+            proxy_pass http://frontend;
+            proxy_http_version 1.1;
+            proxy_set_header Upgrade $http_upgrade;
+            proxy_set_header Connection 'upgrade';
+            proxy_set_header Host $host;
+            proxy_set_header X-Real-IP $remote_addr;
+            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+            proxy_set_header X-Forwarded-Proto $scheme;
+            proxy_cache_bypass $http_upgrade;
+        }
+
+        # API
+        location /api/ {
+            proxy_pass http://api/api/;
+            proxy_http_version 1.1;
+            proxy_set_header Host $host;
+            proxy_set_header X-Real-IP $remote_addr;
+            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+            proxy_set_header X-Forwarded-Proto $scheme;
+        }
+    }
+}
+```
+
+### Scenario 4: Behind Reverse Proxy with Subdomain
+
+If you want API on a separate subdomain:
+
+**docker-compose.yml:**
+```yaml
+services:
+  open-notebook:
+    image: lfnovo/open_notebook:v1-latest-single
+    environment:
+      - API_URL=https://api.notebook.example.com
+      # ... other env vars
+```
+
+**nginx.conf:**
+```nginx
+# Frontend server
+server {
+    listen 443 ssl http2;
+    server_name notebook.example.com;
+
+    location / {
+        proxy_pass http://open-notebook:8502;
+        # ... proxy headers
+    }
+}
+
+# API server
+server {
+    listen 443 ssl http2;
+    server_name api.notebook.example.com;
+
+    location / {
+        proxy_pass http://open-notebook:5055;
+        # ... proxy headers
+    }
+}
+```
+
+### Scenario 5: Traefik
+
+**docker-compose.yml:**
+```yaml
+version: '3.8'
+
+services:
+  open-notebook:
+    image: lfnovo/open_notebook:v1-latest-single
+    environment:
+      - API_URL=https://notebook.example.com
+    labels:
+      # Frontend
+      - "traefik.enable=true"
+      - "traefik.http.routers.notebook-frontend.rule=Host(`notebook.example.com`)"
+      - "traefik.http.routers.notebook-frontend.entrypoints=websecure"
+      - "traefik.http.routers.notebook-frontend.tls.certresolver=myresolver"
+      - "traefik.http.services.notebook-frontend.loadbalancer.server.port=8502"
+
+      # API
+      - "traefik.http.routers.notebook-api.rule=Host(`notebook.example.com`) && PathPrefix(`/api`)"
+      - "traefik.http.routers.notebook-api.entrypoints=websecure"
+      - "traefik.http.routers.notebook-api.tls.certresolver=myresolver"
+      - "traefik.http.services.notebook-api.loadbalancer.server.port=5055"
+    networks:
+      - traefik-network
+
+networks:
+  traefik-network:
+    external: true
+```
+
+### Scenario 6: Caddy
+
+**Caddyfile:**
+```caddy
+notebook.example.com {
+    # Frontend
+    reverse_proxy / open-notebook:8502
+
+    # API
+    reverse_proxy /api/* open-notebook:5055
+}
+```
+
+**docker-compose.yml:**
+```yaml
+services:
+  open-notebook:
+    image: lfnovo/open_notebook:v1-latest-single
+    environment:
+      - API_URL=https://notebook.example.com
+    # No need to expose ports if using Caddy in same network
+```
+
+## Troubleshooting
+
+### Connection Error: Unable to connect to server
+
+**Symptoms**: Frontend displays "Unable to connect to server. Please check if the API is running."
+
+**Possible Causes**:
+
+1. **API_URL not set correctly** for your reverse proxy setup
+   - Check browser console (F12) for connection errors
+   - Look for logs showing what URL the frontend is trying
+
+2. **Reverse proxy not forwarding to correct port**
+   - API should be accessible at the URL specified in `API_URL`
+   - Test: `curl https://your-domain.com/api/config` should return JSON
+
+3. **CORS issues**
+   - Ensure `X-Forwarded-Proto` and `X-Forwarded-For` headers are set in proxy config
+   - Check API logs for CORS errors
+
+4. **SSL/TLS certificate issues**
+   - Ensure your reverse proxy has valid SSL certificates
+   - Mixed content errors (HTTPS frontend trying to reach HTTP API)
+
+### How to Debug
+
+1. **Check browser console** (F12 → Console tab):
+   - Look for messages starting with `🔧 [Config]`
+   - These show the configuration detection process
+   - You'll see which API URL is being used
+
+2. **Test API directly**:
+   ```bash
+   # Should return JSON config
+   curl https://your-domain.com/api/config
+   ```
+
+3. **Check Docker logs**:
+   ```bash
+   docker logs open-notebook
+   ```
+   - Look for frontend and API startup messages
+   - Check for connection errors
+
+4. **Verify environment variable**:
+   ```bash
+   docker exec open-notebook env | grep API_URL
+   ```
+
+### Missing Authorization Header
+
+**Symptoms**: API returns `{"detail": "Missing authorization header"}`
+
+This happens when:
+- You have set `OPEN_NOTEBOOK_PASSWORD` for authentication
+- You're trying to access `/api/config` directly without logging in first
+
+**Solution**: This is expected behavior! The frontend handles this automatically. Just access the frontend URL and log in through the UI.
+
+## Best Practices
+
+1. **Always use HTTPS** in production with reverse proxies
+2. **Set `API_URL` explicitly** when using reverse proxies to avoid auto-detection issues
+3. **Use environment files** (`.env` or `docker.env`) to manage configuration
+4. **Test your setup** by accessing the frontend and checking browser console logs
+5. **Keep ports 5055 and 8502 accessible** from your reverse proxy container
+
+## Additional Resources
+
+- [Docker Deployment Guide](./docker.md)
+- [Security Guide](./security.md)
+- [Troubleshooting](../troubleshooting/common-issues.md)
diff --git a/frontend/src/app/api/runtime-config/route.ts b/frontend/src/app/api/runtime-config/route.ts
new file mode 100644
index 0000000..deb8811
--- /dev/null
+++ b/frontend/src/app/api/runtime-config/route.ts
@@ -0,0 +1,22 @@
+import { NextResponse } from 'next/server'
+
+/**
+ * Runtime Configuration Endpoint
+ *
+ * This endpoint provides server-side environment variables to the client at runtime.
+ * This solves the NEXT_PUBLIC_* limitation where variables are baked into the build.
+ *
+ * Users can now set API_URL in their docker.env and it will be picked up at runtime,
+ * allowing the same Docker image to work in different deployment scenarios.
+ */
+export async function GET() {
+  // Priority:
+  // 1. API_URL from environment (set by user at runtime)
+  // 2. NEXT_PUBLIC_API_URL from build time (fallback)
+  // 3. Default to localhost:5055
+  const apiUrl = process.env.API_URL || process.env.NEXT_PUBLIC_API_URL || 'http://localhost:5055'
+
+  return NextResponse.json({
+    apiUrl,
+  })
+}
diff --git a/frontend/src/lib/config.ts b/frontend/src/lib/config.ts
index 0d50fbc..8b965dc 100644
--- a/frontend/src/lib/config.ts
+++ b/frontend/src/lib/config.ts
@@ -60,11 +60,30 @@ async function fetchConfig(): Promise<AppConfig> {
   console.log('🔧 [Config] Starting configuration detection...')
   console.log('🔧 [Config] Build time:', BUILD_TIME)
 
-  // Try to get from environment variable first (for development)
+  // STEP 1: Try to get runtime config from Next.js server-side API route
+  // This allows API_URL to be set at runtime (not baked into build)
+  let runtimeApiUrl: string | null = null
+  try {
+    console.log('🔧 [Config] Attempting to fetch runtime config from Next.js API route...')
+    const runtimeResponse = await fetch('/api/runtime-config', {
+      cache: 'no-store',
+    })
+    if (runtimeResponse.ok) {
+      const runtimeData = await runtimeResponse.json()
+      runtimeApiUrl = runtimeData.apiUrl
+      console.log('✅ [Config] Runtime API URL from server:', runtimeApiUrl)
+    } else {
+      console.log('⚠️ [Config] Runtime config endpoint returned status:', runtimeResponse.status)
+    }
+  } catch (error) {
+    console.log('⚠️ [Config] Could not fetch runtime config:', error)
+  }
+
+  // STEP 2: Fallback to build-time environment variable
   const envApiUrl = process.env.NEXT_PUBLIC_API_URL
   console.log('🔧 [Config] NEXT_PUBLIC_API_URL from build:', envApiUrl || '(not set)')
 
-  // Smart default: infer API URL from current frontend URL
+  // STEP 3: Smart default - infer API URL from current frontend URL
   // If frontend is at http://10.20.30.20:8502, API should be at http://10.20.30.20:5055
   let defaultApiUrl = 'http://localhost:5055'
 
@@ -82,13 +101,16 @@ async function fetchConfig(): Promise<AppConfig> {
     }
   }
 
-  // Use env var if available, otherwise smart default
-  const baseUrl = envApiUrl || defaultApiUrl
+  // Priority: Runtime config > Build-time env var > Smart default
+  const baseUrl = runtimeApiUrl || envApiUrl || defaultApiUrl
   console.log('🔧 [Config] Final base URL to try:', baseUrl)
+  console.log('🔧 [Config] Selection priority: runtime=' + (runtimeApiUrl ? '✅' : '❌') +
+              ', build-time=' + (envApiUrl ? '✅' : '❌') +
+              ', smart-default=' + (!runtimeApiUrl && !envApiUrl ? '✅' : '❌'))
 
   try {
-    console.log('🔧 [Config] Fetching runtime config from:', `${baseUrl}/api/config`)
-    // Try to fetch runtime config from API
+    console.log('🔧 [Config] Fetching backend config from:', `${baseUrl}/api/config`)
+    // Try to fetch runtime config from backend API
     const response = await fetch(`${baseUrl}/api/config`, {
       cache: 'no-store',
     })
diff --git a/pyproject.toml b/pyproject.toml
index fe22779..f415e30 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "open-notebook"
-version = "1.0.1"
+version = "1.0.2"
 description = "An open source implementation of a research assistant, inspired by Google Notebook LM"
 authors = [
     {name = "Luis Novo", email = "lfnovo@gmail.com"}
diff --git a/supervisord.conf b/supervisord.conf
index 4566751..91949c3 100644
--- a/supervisord.conf
+++ b/supervisord.conf
@@ -28,7 +28,7 @@ startsecs=3
 [program:frontend]
 command=npm run start
 directory=/app/frontend
-environment=NODE_ENV="production",PORT="8502"
+environment=NODE_ENV="production",PORT="8502",API_URL="%(ENV_API_URL)s"
 stdout_logfile=/dev/stdout
 stdout_logfile_maxbytes=0
 stderr_logfile=/dev/stderr
diff --git a/supervisord.single.conf b/supervisord.single.conf
index b9fda4e..707ca8a 100644
--- a/supervisord.single.conf
+++ b/supervisord.single.conf
@@ -40,7 +40,7 @@ startsecs=3
 [program:frontend]
 command=npm run start
 directory=/app/frontend
-environment=NODE_ENV="production",PORT="8502"
+environment=NODE_ENV="production",PORT="8502",API_URL="%(ENV_API_URL)s"
 stdout_logfile=/dev/stdout
 stdout_logfile_maxbytes=0
 stderr_logfile=/dev/stderr
diff --git a/uv.lock b/uv.lock
index 40956ff..bd43de8 100644
--- a/uv.lock
+++ b/uv.lock
@@ -620,15 +620,15 @@ wheels = [
 
 [[package]]
 name = "esperanto"
-version = "2.7.0"
+version = "2.7.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "httpx" },
     { name = "pydantic" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/6d/cf/0da02a603a63b3850abd14d23629f101942db5c18840b0cc6f34d7db9a04/esperanto-2.7.0.tar.gz", hash = "sha256:3861e4e20697813b19f0070a1142934bd6792077c3c174a2c3dd4b6ca0676b06", size = 553433, upload-time = "2025-10-19T02:04:30.21Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/54/8c/a2a9c1e7428d700963e7450aba591b2f4fbcfa61bad88654af8d92df3a00/esperanto-2.7.1.tar.gz", hash = "sha256:a18abc38d30d38c496eac62f252a9c12d243fc49fef7cc92d9d23c5b5faee741", size = 554840, upload-time = "2025-10-19T02:30:45.251Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/14/9c/79827f246965ed66ae8d2f3e3937e552730eaf48b270dac852a4756c7bf4/esperanto-2.7.0-py3-none-any.whl", hash = "sha256:2ea3fa98d8622d08a18dc6701ad362461de02492a3252326c70c969b3aba3db6", size = 129524, upload-time = "2025-10-19T02:04:28.57Z" },
+    { url = "https://files.pythonhosted.org/packages/ee/91/a2c43a4eb3c56f349d59c656783cdd8cd13149a8e521e75f77e84dcd5ac0/esperanto-2.7.1-py3-none-any.whl", hash = "sha256:ea81e531085e32828b2ecd02680088801222dd21e7a73012efdb9b68fa627ed4", size = 129593, upload-time = "2025-10-19T02:30:44.149Z" },
 ]
 
 [[package]]
@@ -2199,7 +2199,7 @@ wheels = [
 
 [[package]]
 name = "open-notebook"
-version = "1.0.1"
+version = "1.0.2"
 source = { editable = "." }
 dependencies = [
     { name = "ai-prompter" },