ALTER SETTINGS CONSTANT writes value but Mendix runtime does not pick it up

[engalar]

Problem

ALTER SETTINGS CONSTANT reports success but the value is not actually available to the Mendix runtime. When the app starts, the constant remains empty.

Reproduction

./mxcli -p CarrefourAgent.mpr -c "ALTER SETTINGS CONSTANT 'AWSAuthentication.AccessKey' VALUE 'AKIAX...' IN CONFIGURATION 'Default'"
# Output: Updated constant 'AWSAuthentication.AccessKey' = 'AKIAX...' in configuration 'Default'

./mxcli -p CarrefourAgent.mpr -c "ALTER SETTINGS CONSTANT 'AWSAuthentication.SecretAccessKey' VALUE '...' IN CONFIGURATION 'Default'"
# Output: Updated constant 'AWSAuthentication.SecretAccessKey' = '...' in configuration 'Default'

Both commands report success. However, when the app is started from Studio Pro, the Bedrock connector page shows:

Required environment variables have not been filled. Please add values for

• AWSAuthentication.AccessKey
• AWSAuthentication.SecretAccessKey

The values had to be manually configured in Studio Pro for them to take effect.

Expected behavior

After ALTER SETTINGS CONSTANT ... IN CONFIGURATION 'Default' succeeds, the value should be persisted in a way that the Mendix runtime reads it on startup.

Possible cause

Studio Pro stores constant overrides in a location that mxcli may not be writing to (e.g., project-settings.user.json, or inside the MPR's internal configuration structure). mxcli may be writing to a different layer that gets overridden or ignored.

Environment

• mxcli: 0.1.0
• Mendix: 11.6.4
• Launch method: Studio Pro (Run Locally)
• OS: Windows 11

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Copied from engalar#46

[github-actions]

Issue Triage

Summary:
The user reports that ALTER SETTINGS CONSTANT commands succeed but the Mendix runtime does not read the updated constant values, requiring manual entry in Studio Pro.

Checklist for bug report

Required info	Present?	Details
mxcli version	✅	0.1.0
Mendix version	✅	11.6.4
Scenario (what was tried)	✅	ALTER SETTINGS CONSTANT … IN CONFIGURATION 'Default' via CLI
Expected output	✅	Constant value should be persisted and read at runtime
Experienced output	✅	Command reports success, but runtime shows constants as empty
AI bug report (mxcli diag --bundle or session log)	❌	Not included

Next steps
Could you please provide the diagnostic bundle (mxcli diag --bundle) or at least the session log from the commands you ran? This will help us see exactly what mxcli is doing and identify why the changes aren’t being picked up by the Mendix runtime.

Thank you for reporting the issue!

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