Flags were natively supported in Rust (the hanzo-flags crate — the evaluation
core, pub-exported for Rust callers and FFI-exported for the rest), Go (in-process
via CGO to that core), and TypeScript (@hanzo/flags over /v1/flags). Python was the
gap. This closes it.
hanzo-flags POSTs an evaluation context to cloud /v1/flags — the same
PostHog-compatible endpoint every other client speaks — and answers is_enabled /
variant / payload from the response. It mirrors @hanzo/flags exactly: a HanzoFlags
client bound to one host, load(distinct_id, person_properties=, groups=), the same
three-field result, an async twin, and a one-shot evaluate().
Two invariants match the family: fail-open (a transport error yields the last good
or empty result with errors_while_computing set, never a raise on the hot path)
and cache-by-context+TTL. Zero runtime dependencies — stdlib urllib only, so a
flag check never drags httpx/pydantic into a service.
Tests stand up a local /v1/flags stub and prove the request shape is
PostHog-compatible, the accessors resolve booleans/variants/payloads, the TTL
cache holds, and both a 5xx and an unreachable host fail open. 7/7 green.
zeekay