Custom Docker Container with SSL

Custom Docker Container with SSL

If you want to run a Node.js app, a Python API, or any other web application on the same server as your WordPress sites — without juggling separate hosting accounts — custom Docker containers are your answer. FlyWP handles the SSL certificate (the padlock that enables secure HTTPS connections) and the reverse proxy (the traffic router that connects your domain to your app) automatically, so you can focus on your application instead of server configuration.

Tip

This feature is for developers who want to host custom applications alongside WordPress. If you need popular self-hosted tools like phpMyAdmin, n8n, or Nextcloud, check One-Click Apps first — they are preconfigured and ready to deploy in one step.

How It Works

When you deploy a custom Docker container (Docker is a system for packaging applications and their dependencies into portable, self-contained units called containers) on a FlyWP server, the platform:

1. Runs your container with the specified image and configuration
2. Provisions an SSL certificate for your chosen domain via Let’s Encrypt (a free, widely trusted certificate authority)
3. Configures NGINX (a high-performance web server that also acts as a reverse proxy) to route traffic from your domain to your container’s internal port

Your application becomes accessible over HTTPS without any manual certificate management or server configuration on your part.

Setting Up a Custom Container

Prerequisites

Before deploying, make sure you have:

• A FlyWP server with available resources (CPU, memory, disk)
• A domain or subdomain with its DNS (Domain Name System — the system that maps domain names to IP addresses) pointed to your server’s IP address
• The Docker image you want to deploy, available from Docker Hub or a private registry

Deployment Steps

1. Navigate to your server in the FlyWP dashboard.
2. Create a new site using the domain you want your application to run on.
3. Configure the Docker image and port mapping for your application.
4. FlyWP provisions the container, SSL certificate, and reverse proxy automatically.

Port Mapping

Your container listens on an internal port, and NGINX forwards incoming web traffic to it. FlyWP maps the domain’s traffic through NGINX like this:

Client (HTTPS:443) -> NGINX -> Your Container (internal port)

Note

Only HTTP-based applications can be routed through NGINX this way. If your application uses a non-HTTP protocol (such as raw TCP), you may need to expose the port directly through the server’s firewall instead.

SSL Certificates

FlyWP automatically provisions Let’s Encrypt SSL certificates for custom containers. Certificates are:

• Issued automatically when the site is created
• Renewed automatically before expiration
• Terminated at the NGINX level — your container receives plain HTTP traffic internally, keeping the setup lean

Use Cases

Not sure if this feature applies to you? Here are the most common reasons developers reach for custom containers:

• Custom web applications — Node.js, Python, Go, or Ruby apps that need their own domain
• APIs and microservices — backend services that should be accessible over HTTPS
• Admin tools — self-hosted dashboards, monitoring UIs, or internal tools
• Headless CMS — a headless WordPress or other CMS running alongside your main site

Custom containers share server resources with your WordPress sites. Monitor CPU and memory usage to avoid your custom applications degrading WordPress performance.

Related Pages

• One-Click Apps
• Managing Services
• SSL Certificates
• Firewall