Comment by hobofan

> You see a hundred blog posts of "why you should experiment with your pricing", but actually doing that is often such a pain that nobody ends up doing that (and admittedly the reason why I would have shied away from such projects in the past).

Yes, exactly. Especially when those same blog posts tell you to plan to basically have your whole team focus on it for 3 months, as if you have nothing else to do!

> - What are your plans like regarding the integration of entitlement checking in the service and SDK? As far as I can tell, that's still a missing piece? I really love how oso[0] has managed to separate the authorization checking from the authorization definition via their DSL and SDKs. Ever since I saw that, I was wondering if a very similar system could work for entitlement checking.

The SDK does expose a `tier.limit(org, feature)` method[1]. This is reasonably fast, but if it's uncached, it is an API call to Stripe, so it can be beneficial to have that drive a proper feature-flagging system like Launch Darkly, or whatever else you use to manage authorization and feature availability.

> - I think where your system could provide a lot of benefit would be in help tracking usage metrics that can be harder to calculate (and with that more of a pain to use). It's already nice not having to implement a simpler "number of action N taken the last billing period" metric. However something like a "N number of active users last billing period", where you now would also have to keep track of which users you have already seen before to prevent double-counting them becomes increasingly annoying to implement.

For seats you could use an `"aggregate": "perpetual"` setting on the feature. See: https://www.tier.run/docs/recipes/#simple-per-seat-pricing (that page also has some other examples that might be helpful.) With that, you'd just report the increase or decrease every time the seat count changes, and the counter would never be reset. (There's a few other ways to approach it, but that's what I'd do, as it's probably the simplest.)

You're right, though, if you want to charge based on active users, then it gets a bit more tricky, because you do have to avoid double-counting. And the precise definition of "active" becomes really important. I'd probably approach it by putting a "lastSeen" timestamp on each user account, and then periodically calling `tier.report(org, "feature:activeusers", numberActiveSinceFirstOfMonth, Date.now(), true)` to clobber any previous value. (`clobber` is not the default, since usually you want Tier to count it for you.) I'll add an "active users" example to that recipes page.

[1]: https://www.npmjs.com/package/tier#user-content-limitsorg