Is Microsoft’s VS Code really open source?
In June, Databricks opened up all Delta Late APIs as part of the new Delta Lake 2.0 release. This put a definitive end to criticism from competitors like Cloudera, Dremio, Google (Big Lake), Microsoft, Oracle, SAP, AWS Snowflake, HPE (Ezmeral) and Vertica, who had doubted that Delta Lake was open source or proprietary.
“The new announcement should provide continuity and clarity for users and help counter confusion (partly fueled by competitors) about whether Delta Lake is proprietary or open source,” said Matt Aslett, director of research at Ventana Research.
This is not the first time that there has been ambiguity over the open source nature of a tool. The best example is Microsoft’s VS Code.
Last month, Rukshan Ranatunge, Member – FHIR Implementation Architecture and Technical Advisory Group of the Ministry of Health – Sri Lanka, mentioned in a blog post that he is moving from VS Code to VS Codium. In the Publishhe talked about VS Code not being open source and also what makes VS Code proprietary.
Also, in June, Licio LentimoCybersecurity Technical Mentor at CYDEO and software developer, tweeted, “VS Codium is the open-source alternative to VS Code. Interestingly, Microsoft’s VS Code is not fully open source as many previously thought.
What is VS Code?
An important aspect of the source code editor is that it can be customized using extensions. These extensions support new programming languages, themes, and debuggers and perform static code analysis.
With the built-in source control feature, users can access control settings and view changes made to the current project. Additionally, this feature also allows users to create repositories and make push and pull requests directly from the Visual Studio Code program.
How open is VS Code?
Microsoft released the open-source beta version of VS Code in November 2015. At the same time, it released the VS Code deposit. However, this does not mean that VS Code is open-source. Instead, it’s more accurate to say that VS Code is built on an open source project called Code-Open Source Software (Code-OSS). Code-OSS is the core layer of VS Code. It is available on GitHub under the standard MIT license.
The GitHub repository (Code-OSS) is where Microsoft develops the VS Code product. Here, developers write code and modify it. They also publish their roadmap and monthly iteration in the GitHub repository.
However, Microsoft VS Code is a Microsoft-licensed distribution of ‘Code – OSS’ which includes Microsoft proprietary assets and features like Visual Studio Marketplace integration and telemetry system that are not available in Code-OSS. So Microsoft follows an “open core model” for VS Code and is not truly open source.
In an open-core model, the company offers certain limited features that form the core of the product as free and open-source software (FOSS), while several add-on features are released as proprietary.
Not only Microsoft, but several other companies are deploying the open core model. For example, Google built Chrome on Chromium, an open-source browser, and then modified it to incorporate Google’s proprietary features, which are released as proprietary freeware. The same goes for Oracle JDK, Xamarin Studio, and JetBrains. These apps were built on OpenJDK, MonoDevelop, and IntelliJ, respectively.
“Microsoft is modifying VS Code in such a way that a non-Microsoft VS Code fork cannot use extensions from the official Microsoft VS Code store. Also, some of the VS Code extensions developed and released by Microsoft will only work in the VS Code released by Microsoft and will not work on non-Microsoft VS Code forks,” Ranatunge mentioned in his blog post.
Microsoft has made similar moves in the past. He modified the MonoDevelop open source cross-platform IDE like Visual Studio for Mac. Visual Studio for Mac has three versions – for students, professionals, and businesses. While the student version is free and supports classroom learning, individual developers and small businesses must login through IDE to access other versions.
In 2021, Microsoft suddenly rremoved hot reload functionality of the open-source .NET SDK, only to revoke it later because it had enraged the .NET community.
Go to VS Codium
As noted, Microsoft follows an open core model for VS Code. Therefore, developers who wish to access the full open source code under the MIT license will need to download the code from the repository and then build the VS Code themselves.
The task is heavy for most users. This is where VS Codium comes in. VS Codium is a fully open source binary of VS Code under the MIT license. With VS Codium, developers don’t need to download and build from source. Instead, the VS Codium team builds VS Code from the source repository and uploads the binaries to GitHub. “VS Codium is a Microsoft Visual Studio Code clone. The sole purpose of this project is to provide you with ready-to-use binaries without Microsoft’s telemetry code,” said Abhishek Prakash, creator of It’s FOSS (an open source-focused web portal), in a Blog.
With telemetry tracking, developers are often inundated with unnecessary ads for premium versions of the various extensions they use. VS Code gives users the ability to install Microsoft and third-party extensions. Unfortunately, these extensions may collect their usage data, which cannot be disabled by disabling telemetry tracking.