Add Specifying The Server Port as a phoenix til

README.md

@@ -7,7 +7,7 @@ variety of languages and technologies. These are things that don't really
 warrant a full blog post. These are mostly things I learn by pairing with
 smart people at [Hashrocket](http://hashrocket.com/).
 
-_510 TILs and counting..._
+_511 TILs and counting..._
 
 ---
 
@@ -214,6 +214,7 @@ _510 TILs and counting..._
 - [Bypass Template Rendering](phoenix/bypass-template-rendering.md)
 - [Check The Installed Version](phoenix/check-the-installed-version.md)
 - [Render A Template To A String](phoenix/render-a-template-to-a-string.md)
+- [Specifying The Server Port](phoenix/specifying-the-server-port.md)
 
 ### PostgreSQL
 

phoenix/specifying-the-server-port.md

@@ -0,0 +1,30 @@
+# Specifying The Server Port
+
+Running `mix phx.server` for a Phoenix project with the default settings
+will attach the server to port `4000`.
+
+If you'd like to use a different port in development, you can change it in
+`config/dev.exs`.
+
+```elixir
+config :profilex, Profilex.Web.Endpoint,
+  http: [port: 4444],
+  ...
+```
+
+Alternatively, you can allow it to be configurable from the command line
+with an environment variable and a fallback port.
+
+```elixir
+config :profilex, Profilex.Web.Endpoint,
+  http: [port: System.get_env("PORT") || 4000],
+  ...
+```
+
+Running
+
+```bash
+$ PORT=4444 mix phx.server
+```
+
+will launch the server on port `4444`.