Reserved & Injected Variables
See which environment variable keys Out Plane reserves, which variables it injects into your running app, and the 5000 character limit per value.
You set environment variables on any application from its Environment variables settings. A few keys are reserved, and one size limit applies.
Reserved Keys
You cannot set these keys. Out Plane rejects them when you save.
| Key or prefix | Notes |
|---|---|
HOSTNAME | Set automatically for each running instance. |
OP_* | Any key starting with OP_ is reserved for Out Plane system variables. |
KUBERNETES_* | Any key starting with KUBERNETES_ is reserved by the platform. |
HANGAR_* | Any key starting with HANGAR_ is reserved for Hangars. |
PORT is not reserved. Set it yourself, or have your app read it to know which port to
listen on.
Value Size
Each environment variable value can be at most 5000 characters.
Injected Variables
Out Plane injects a small set of system variables, all prefixed OP_, into your running
application. Because the OP_ prefix is reserved, your own variables never collide with them.
A Hangar gets HANGAR_NAME and HANGAR_AGENTS instead, plus
HANGAR_REPO_URL and HANGAR_REPO_BRANCH when it was created with a repository.
Instance Sizes
Learn how an instance size sets the vCPU and memory of each app instance, how per minute pricing works, and where to find current sizes and prices.
URL Format
Learn how Out Plane builds the default HTTPS URL for each public port from the app name, port, and team slug, and how TCP ports get an address.