🟢 Wire OpenFeature + flagd into a Spring Boot service with zero setup : Adventure 04 | Beginner

[simon.schrottner]

The Aletheia Institute’s lab has been recording every subject as "untreated" for the past eight months — the OpenFeature integration was never finished, and the lab director assumed the system was reading the chart. Your job: wire the OpenFeature Java SDK against a flagd sidecar, author the first flag in flags.json, and prove the lab can change what it records without restarting anything — of course without setup headache again.

What You’ll Learn

• OpenFeature Java SDK basics — provider registration, evaluation details, fallback values
• flagd as a sidecar in Resolver.RPC mode, watching flags.json from disk
• Hot-reload of flag definitions without redeploying the application
• Spring Boot wiring of an OpenFeature client at startup

Deadline

Tuesday, 26 May 2026 at 23:59 CET

You can still complete the challenge after this date, but points will only be awarded for submissions before the deadline.

Get Started

Start the Challenge

Discussion

Share your solutions, your questions, and the moment you realised the lab had been lying for eight months. We’re looking forward to seeing how you wire it up.

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Other levels

• Intermediate: Outcome by cohort (coming soon)
• Expert: Read the chart (coming soon)

[theharithsa]

It was a cool challenge. Thanks, Simon.

Tip: For me, when Codespaces started, the ports were private. After changing the port visibility to Public, the website started to load; otherwise, we got a 502 error.