issues with SSIS projects Deployment via AzureDevops

I’m having an issue with my SSIS projects that I need help diagnosing and resolving. Below is a concise summary of the problem, the environment, and everything I've tried so far.

Summary • When the SSIS project is deployed via our Azure DevOps YAML pipeline to the Integration Services Catalog (SSISDB), the pipeline completes successfully but the changes made in the project are not reflected in the deployed package. • Deploying the same project manually from Visual Studio 2019 successfully deploys the changes. • Manually incrementing the project’s VersionBuild and then running the Azure DevOps pipeline also results in a successful deployment of the changes.

Observed evidence • The built .ispac produced by the pipeline contains the updated .conmgr (and other changed files), but the project.manifest inside the .ispac still contains the old values. • This behavior occurs for any change made to the project (not limited to connection managers).

Environment • Azure DevOps YAML pipeline (self-hosted agent) • Build agent is Windows-based but does not have Visual Studio / SSIS build tooling consistently available • SSISBuild and SSISDeploy tasks are used in the pipeline

What we have tried so far (actions and verification steps)

Ensured pipeline checkout and workspace cleaning • checkout: self with clean: true and workspace: clean: all were configured. • Added a git info step to confirm branch and latest commit in the build logs.

Forced unique build outputs • Added a BUILD_TAG (using $(Build.BuildId)) and built to a unique output folder $(PROJECT_NAME)_$(BUILD_TAG) so each run produces a distinct ISPAC path.

Cleaned intermediate outputs before build • Added steps to remove bin/obj folders and any previous ISPAC outputs from the artifact staging directory to avoid incremental/cached artifacts.

Built with SSISBuild and inspected the ISPAC • Ran SSISBuild to produce the ISPAC into the unique output folder. • Extracted the ISPAC in the build pipeline (using .NET Zip API) and printed file listings, timestamps, .conmgr contents, and project.manifest contents to the build logs for verification. • Observed that .conmgr (and other changed files) are present and show updated timestamps, but project.manifest still contains the old values and an older timestamp.

Manual verification and local testing • Manual deployment from Visual Studio 2019 (on a machine with SSDT/SSIS tooling) deploys the changes correctly. • Manually changing VersionBuild in the project and then running the pipeline causes the pipeline to deploy the updated package (indicating the deploy step picks up a new ISPAC when the filename or version changes).

Diagnosis so far • The packaging step that generates project.manifest is not regenerating the manifest from the updated compiled artifacts on the build agent. The manifest appears to be created from stale or cached inputs on the agent.