Update tech radar

[cristiklein]

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• I'm aware of the Contributor Guide and did my best to follow the guidelines.
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Links to code snippets reference line numbers.
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You can find such links with egrep -R '\[.*\]\(.*user-demo.*#L.*)' docs.

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[viktor-f]

I like the new organization of the items in the radar 👍
But I find it a bit hard to see if you also did some changes to what was in the radar or if it looks any different, without going through each item one at a time. Could you write here if there is any change to which items are in the radar, where they are in the radar or if the radar otherwise looks any different?

[cristiklein]

Good comment @viktor-f ! Indeed, I should have separated my commits to split presentation from content changes. My bad!

Here is a summary of changes:

"Meta" Changes

• Updated date in title (Welkin Tech Radar — 2025-11-25)
• Changed quadrant name ("Tools" → "Tools (non-CNCF)") and moved items in "CNCF Projects" correctly.
• Removed unused fields (active and moved)
• Increased size of "ADOPT" ring.

Removed / Downgraded Items

• Ingress Nginx (moved to HOLD)
• Istio (moved to HOLD, given that we will invest heavily in Cilium)
• Jaeger (moved to HOLD, given that we only support it as a self-managed service)
• OAuth2 (felt unnecessary and misplaced, already represented by Dex)
• Redis (moved to HOLD)
• Terraform (moved to HOLD)

Added / Upgraded Items

• Cilium (moved to ADOPT)
• Fluentbit (added to ASSESS)
• Javascript (added to ADOPT) -- As agreed in some product team meeting, QA uses Javascript heavily
• Kubernetes (added to ADOPT -- No clue why we left it out previously, probably it was too obvious)
• OpenTofu (added to ADOPT)
• Valkey (added to ADOPT)

Mkey, now that I see how much changed and how difficult it is even for me to produce a diff, I won't be upset if you reject this PR and ask me to split it into several commits. 😄

[viktor-f]

Thanks, this is exactly the information I wanted. I'm fine with keeping it as one commit, but as you say it would be easier to follow if it was two commits.

[Carl-Elastisys]

Hi!
A bit late to the party, but looked at the new version and wondered if it is intentional that Argo CD was moved from Adopt to Hold during this update?

[cristiklein]

Thanks for noticing @Carl-Elastisys . Argo CD is totally ADOPT. I fixed that in #1216