Often these 3rd party offerings are feature flags PLUS experimentation with user segmenting. Depending on the style of software you build, this can be extremely valuable; it’s very popular in the SaaS market for a reason.

Early on at Notion we used simple percent rollout in Redis, then we built our own flag & experimentation system, but as our needs got more complex we ended up switching to a 3rd party rather than dedicating a team to keep building out the internal system.

We will probably hit a scale in a few years where it makes sense to bring this back in house but there’s certainly a sweet spot for the 3rd party version between the 50-500 engineer mark for SaaS companies.