From 551833d3d11bd4cd88ba8b6e0576ba140b061094 Mon Sep 17 00:00:00 2001
From: Ed Morley <501702+edmorley@users.noreply.github.com>
Date: Wed, 27 Mar 2024 16:39:42 +0000
Subject: [PATCH] Correct specification for deprecated `CNB_STACK_ID`

Restores the specification for `CNB_STACK_ID` to the definition that was used prior to the docs refactor in #335.

Fixes #396.

Signed-off-by: Ed Morley <501702+edmorley@users.noreply.github.com>
---
 platform.md | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/platform.md b/platform.md
index 3795578..b3b6f95 100644
--- a/platform.md
+++ b/platform.md
@@ -1570,10 +1570,13 @@ _Deprecated in Platform API 0.12._
 
 For compatibility with older platforms and older buildpacks, base image authors SHOULD ensure for build images and run images:
 
-- The image config's `Env` field has the environment variable `CNB_STACK_ID` set to the stack ID.
 - The image config's `Label` field has the label `io.buildpacks.stack.id` set to the stack ID.
 - The image config's `Label` field has the label `io.buildpacks.stack.mixins` set to a JSON array containing mixin names for each mixin applied to the image.
 
+And for build images:
+
+- The image config's `Env` field has the environment variable `CNB_STACK_ID` set to the stack ID.
+
 Where `CNB_STACK_ID` SHALL be directly inherited by buildpacks without modification.
 
 To upgrade, the platform SHOULD upgrade all buildpacks to use Buildpack API `0.10` or greater.