atlas by clearpeople

What the end of LTS for .Net Core 3.1 means for Atlas clients

3 October 2022

LTS, in this context, stands for Long Term Support. And for Microsoft that means something like 3 years. (Yes, that might not be very long-term in your reckoning). 

In this blog I want to highlight 13 December 2022 – the date when Microsoft support for .Net Core 3.1 ends – and why it’s important for all Atlas customers to upgrade to Atlas 4.0 before that deadline.

net core 3.1 out of long term support

End of support means that staying on the unsupported version is no longer an option as it will expose you to security risks. As Microsoft will neither support nor deliver hotfixes for .NET Core 3.1 after 13 December this year, it’s important to realise that staying on the old .Net version opens your systems up to security risks or cause support issues that cannot be resolved. Thus we’re asking all our clients to make sure they upgrade to Atlas 4.0 before 13 December 2022.

To give you some insight into why Atlas is affected by the end of LTS for .Net Core 3.1, I’ll take you back to early 2021 when ClearPeople made the ambitious decision to revamp most of the backend pieces of Atlas. We needed to do this to create a solid basis for developing the features we had in our roadmap. This is a challenge familiar to the technology sector and happens every now and then – particularly if you’re growing rapidly.

Fortunately, we were able to keep evolving other areas of Atlas and, importantly for a product company like ours, we didn’t need to pause the development of new features. (Evernote, for example, spent 18 months fixing their technical debt in order to prepare for the future.)

At that point, Microsoft had just released .Net 5 but that version wasn’t supported by Azure Functions (the released workaround, enabling us to run Functions in isolated mode, did not work very well). So we decided to do our revamp using .NET Core 3.1 LTS. That version, released in December 2019, was fully supported by Azure Functions, and our dev team was already quite experienced with it.

However, with Microsoft terminating the .Net Core 3.1 LTS we needed to be proactive about our long term support, which is why, as of Atlas 4.0, we’re now using .Net 6.

With .Net 6 we should be good until at least 12 November 2024 according to current guidance on the release lifecycle. You can find dates for when support ends for different versions and read the .NET Support policy here: .NET and .NET Core official support policy ( In the overview you’ll notice that .NET Core 3.1 reaches ‘end of support’ on 13 December 2022.

As staying on the unsupported version of .NET leaves you open to security or support issues, we’re reminding all our clients to upgrade to Atlas 4.0. Our Customer Success Agents are available to guide you through the move to Atlas 4.0 in time for that December deadline and will ensure you keep your digital workplace secure and performing well.

Author bio

Patrick Proesmans

Patrick Proesmans

As Head of Success I’m responsible for all activities related to the full customer success journey. We want to provide our clients the best possible customer experience and meet customer expectations. When I’m not working I try to keep the weeds out of my garden and to enjoy the Spanish sun in the Alicante area.

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