Show HN: FFlags – Feature flags as code, served from the edge (opens in new tab)

Writing your own logic to handle flags is trivial at first, especially if you're running a monolithic app, but quickly grows in complexity:

- distributing flags to multiple services

- broadcasting updates

- caching rules

- audit logs

- product, not eng, will start managing the flags at some point and needs easy access

- custom logic for gradual rollouts, A/B testing

- custom attributes support (used in evaluation)

- managing multi-variant flags

- supporting multiple platforms (backend, frontend, native apps, services, jobs) and evaluation strategies (eager server-side evaluation vs shipping a client-side engine)

There are quite a few open-source options like Growthbook, Flagsmith, go-feature-flag, and Unleash that you can check out for comparison.

A lot of "engineers" nowadays don't know the concept of per-user/customers configs and how to build/expose them to non-technical staff.

The main appeal of feature flags is simplicity and being a low-hanging way to apply per-customer/user configuration, few platforms allow true a/b testing (amplitude comes to mind but I'm sure there are more).

You are right, feature flags are just toggles but the devil is in the details. When the product scales you would want to test things internally or with a close group of people on prod before you make it public (beta releases). Sometimes you would want to release features at a specific time (Apple, Figma product launches). Sometimes you would want to test if A is working better than B (A/B testing typically in eCommerce sites). Sometimes features are location-specific (Different content for different countries, netflix does this). Let's consider a scenario: You have a team of 10 engineers working on 5 different features. They merge their feature branches to a main branch which gets deployed at the end of the release cycle. Now, if one of those features isn't working as expected, the engineers will have to roll back to the last deployment which won't have any of the 5 features. With feature flags, this could be avoided by developing all features behind a feature flag.

Likewise, while the idea of sticking the determination of whether a given feature is enabled or not in a REST service would make sense, it's not at all clear why you'd ever want to farm that out to another provider, apart from the rare case when you're making a static website with no backend at all.

If you have any kind of back-end infrastructure, it'd seem trivial to implement this yourself. Doing it yourself also allows you to make the feature flags more controlled, e.g. by some flag associated with the current user such as opting into experimental features.

For efficiency, I'd also want to batch a bunch of such flags together, so e.g. when a use logs in they get a list of enabled features that gets cached locally, rather than having to query each and every one via REST.

So I'd echo the question, what problem is this solving?

I had the same question after quickly reading the docs.

I am probably not directly an intended user but I sure would be glad to understand what this is (as an amateur dev)

These features are in pipeline. It is currently targeting the developers to help them with rollbacks and release management.

That's a fair point! Basic feature flags are just toggles, true and false. But they quickly become complex as you onboard new customers and scale. You need percentage rollouts to make sure things are working before everyone starts using the features. It only makes sense for engineers to spend time building actual features and testing them in production rather than spending bandwidth on building a feature flag management tool or managing the service for the same. This is a typical build vs buy debate. :D

I thought it's satire. Like "/dev/null as a service".

Aah! That's a miss from my end. I had it on my previous landing page. It is 100k requests a month. But, I am not adding any cap right now. I monitor the system all the time so if it goes above the free tier limit significantly I will notify.

Hey, Thanks! I recorded it using https://screen.studio/.

That was the main pain-point I faced in the orgs I have worked with. When I came to know about the OpenFeature I was instantly gravitated towards building this on open standards.

Thank-you! Do let me know how was your experience if you to use it.