Map the Stack Before You Deploy

Lesson outcome

You will be able to describe the stack in plain English, identify the major service boundaries, and explain what depends on what before anything new is deployed.

Why this matters in an agency

Owners get into trouble when infrastructure looks like a pile of tools instead of a system. If you do not know which layer owns application runtime, persistent data, access, and observability, every outage feels mysterious. A simple topology map changes that. It lets you reason about change before you make it, and it gives you a faster path through troubleshooting when something breaks under client pressure.

Inputs, tools, and prerequisites

You need the current infrastructure notes, access to the existing deployment environment, and a place to sketch the stack. Use the master index and current-status notes as the internal source of truth. Current official Coolify installation and documentation pages help verify platform assumptions where the local notes may lag behind product changes.

Step-by-step walkthrough

Start by listing the three main layers in the simplest possible terms: app hosting, data services, and access and routing. Then place your actual tools into those layers. For example, an application host or Coolify box sits in the app layer, PostgreSQL and Redis sit in the data layer, and Tailscale, SSH, DNS, and reverse proxy sit in the access layer. If a service spans layers, note that explicitly rather than pretending the system is cleaner than it is.

Next draw the dependency flow. Ask what must be working before the website or internal tool can respond correctly. Usually the route is user request to DNS and proxy, then app runtime, then data store. If any one of those is misconfigured, the visible failure can show up somewhere else. That is why topology matters. Owners do not need kernel-level knowledge, but they do need to know which dependency to inspect first.

Then mark the shared services. These are the pieces whose failure affects multiple apps or clients, such as the database server, the reverse proxy, or a shared auth layer. Shared services need extra caution because a seemingly small change can have a wide blast radius.

Finish by creating a one-page topology note for yourself. Include each server, its role, the services it hosts, the critical ports or entry paths, and the monitoring surface you would check first. This note is what you use before a deployment, during troubleshooting, and when onboarding someone else into the stack.

Failure modes and verification checks

The biggest failure is a topology diagram that is too abstract to use. Another is forgetting shared dependencies. Verify the map by picking one live app and tracing the full path from URL to database. If you cannot explain the path from memory after using the map, the map still needs work.

Implementation checklist

• List app, data, and access layers.
• Assign each live service to a layer.
• Mark the dependency order from request to response.
• Flag shared services with wider blast radius.
• Store the map in a note you can actually update.

Immediate next action

Create a one-page stack map for the environment you use right now and trace one customer-facing request through it.