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Technical6 min read

Unified developer experience (UDE): what changes for X++ developers

UDE: X++ code is written locally in Visual Studio and runs in a cloud environment managed through Power Platform. What changes and what stays.

The short answer

With the unified developer experience (UDE), Dynamics 365 Finance & Operations development still happens in Visual Studio, but the architecture changes: the developer keeps metadata and X++ source code locally (development tier), while execution happens in a cloud environment holding the data and running X++ (execution tier). These environments, Unified Developer Environment (UDE) and Unified Sandbox Environment (USE), are provisioned and managed in the Power Platform admin center, with Dataverse.

Microsoft says most F&O developers' workflows stay the same: models, projects, builds, debugging. What mainly changes: deployment to the runtime, provisioning and access to logs.

What changes day to day

  • Setup: Power Platform Tools Visual Studio extension, connect to the environment, download metadata and configure the reference metadata folders.
  • Work cycle (Microsoft tutorial): create a model, write and build the class, deploy it to the cloud runtime, then debug the deployed code.
  • Tests: test code must be deployed to the environment to run, and needs Application Foundation and Test Essentials. See first SysTest unit test.
  • ISV packages: put the modules in a common folder added to the reference metadata.
  • Logs: if a deployment fails, a log download link is provided in Visual Studio's output pane, and the history is available on the Dataverse side.
  • Environment type: a USE cannot become a UDE, or the reverse; you create a new one.

Why it matters

UDE brings F&O and Power Platform closer: dual-write and virtual tables let you combine F&O and Dataverse data. It is also the environment required for some new features: developing X++ AI tools for agents requires a unified developer environment. See Copilot Studio agents: what still needs X++ and Dynamics 365 ERP MCP server, which runs on UDE or Tier 2, not on legacy CHE environments.

For automation, the "Dynamics 365 Finance and Operations Tools" Azure DevOps extension creates the package, adds ISV licences and applies the package: see Azure DevOps build pipeline.

Common mistakes

  • Forgetting to deploy code (tests included) before running: the cloud runtime only has what was deployed.
  • Not adding ISV modules to the reference metadata: build errors.
  • Trying to convert a USE into a UDE: impossible, you provision a new environment.
  • Ignoring operation logs when a sync fails: they can be downloaded from Visual Studio.

And at Skalp AI?

Skalp does not deploy to your environments: code arrives as a pull request in your Azure DevOps project, which your team then deploys to its UDE or environments. Skalp AI writes the specification, generates the X++ code and unit tests, compiles with a best-practice check, then delivers a pull request to your Azure DevOps: nothing is merged without your technical architect's approval. See Azure DevOps integration, the bigger picture in building X++ without a consultant in 2026, and the Basic, Pro and Max plans (1 credit, ≈ €400 on Basic, €200 on Pro, consumed only when the code is generated).

Sources

Frequently asked questions

Does X++ development change with UDE?

The language and Visual Studio stay. What changes: code runs in a cloud environment managed through Power Platform, to which you deploy from Visual Studio.

What is the difference between UDE and USE?

UDE is a development environment, USE a sandbox-type environment. The type is fixed at creation and cannot be converted.

Do unit tests work in UDE?

Yes, provided the test code is deployed to the environment; Application Foundation and Test Essentials are required.

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