Package and API index

Developer index. Full call surfaces live on the SDK pages. Do not treat registry install commands as working unless the publish row says so.

Pre-release. License MIT; do not redistribute packages built from the SDK repository until the license is ratified and publication is authorized.

Packages

Surface	Package	Version in tree	Published?	Runtime (manifests + CI)
Node / Bun / Deno	`@fireweaveai/sdk`	`2.1.0`	Published. npm 2.1.0; dist-tag latest = 2.1.0 (as of 2026-08-17). CHANGELOG/docs previously described 2.1.0 as unpublished and `latest` as 2.0.0.	Node `>=20.20`; CI Node 20 + 24, Bun 1.2.0 + latest, Deno `v2.x` + canary
Python	`fireweave`	`0.1.0`	Published. PyPI 0.1.0 — `pip install 'fireweave[openfeature]'` is valid	Python `>=3.10`; CI 3.10 + 3.14
Go	`github.com/FireWeave-HQ/fireweave-sdk/sdks/go`	`0.1.0` (matrix); `go.mod` is `go 1.25.12`	Unpublished as a tagged module	Go 1.25; CI `1.25.x` + `stable`
Java	`ai.fireweave:fireweave-{sdk,openfeature,adapter-posthog,testing}`	`0.1.0-SNAPSHOT`	Unpublished. Parent POM: “DO NOT PUBLISH.” `groupId ai.fireweave` is a working assumption	Java 11+; CI JDK 11 + 25
Browser	`@fireweaveai/web-sdk`	`2.1.0`	Published. npm 2.1.0 (as of 2026-08-17)	Browser. CI: Bun + happy-dom. Not a Node/Deno target

Zero runtime dependencies on Node, Python core, and Web. OpenFeature is a peer (Node/Web) or an extra (Python). Go requires the OpenFeature and PostHog modules listed on the Go page. See Compatibility for the adapter and type matrix.

OpenFeature pins

Binding	Provider	Pin	Notes
Node	`FireweaveProvider`	`@openfeature/server-sdk` `^1.22.0`	`lazyReady` default true. Deno OF provider import is Node/Bun-gated in CI
Python	`fireweave.openfeature.FireweaveProvider`	`openfeature-sdk>=0.10.0,<0.11`	Extra `fireweave[openfeature]`; pre-1.0
Go	`openfeature.NewProvider`	`go-sdk` `v1.17.2`	Wraps `*fireweave.Client`
Java	`ai.fireweave.openfeature.FireweaveProvider`	`dev.openfeature:sdk` 1.15.1	Not 1.21.0
Web	`FireweaveWebProvider`	`@openfeature/web-sdk` `^1.9.0`	Sync resolvers; `runsOn = 'client'`; name `fireweave-web`

Tracking (spec §6): not implemented. Details: OpenFeature.

Env vars and config

Name	Who reads it
`FW_API_URL`	Node, Python, Go remote adapters
`FW_PROJECT_API_KEY`	Node, Python, Go remote adapters
`FW_DEPRECATION_WARNINGS`	Node, Python (`=1` → one `client.flags` notice)

Java: constructor / FireweaveConfig only. Web: constructor only. Timeouts: request 3000 ms, shutdown 10000 ms. Host allowlists and https rules: Configuration. Example-only (not SDK core): FIREWEAVE_POSTHOG_KEY, FIREWEAVE_POSTHOG_HOST, FW_POSTHOG_HOST, FW_SECRET_KEY.

Adapters (quick map)

Adapter	Node 2.1	Python	Go	Java	Web
`FireweaveRemoteAdapter`	yes	yes	yes	yes	`FireweaveRemoteWebAdapter`
`InMemoryAdapter`	yes	yes	yes	`fireweave-testing`	`InMemoryWebAdapter`
Local / dev	`FireweaveLocalAdapter`	`FireweaveLocalAdapter`	absent	absent	`FireweaveLocalWebAdapter`
PostHog	removed	`fireweave[posthog]`	`adapters/posthog`	seam only (`create(config)` → `UnsupportedCapability`)	none

Errors

15 kinds, evaluation never throws. Full table: Errors. Node/Web: FireweaveError. Python: per-kind classes + ErrorKind. Go: fireweave.Error. Java: ErrorKind + FireweaveException.

Language gates (do not paper over)

API	Node	Python	Go	Java	Web
Product namespace	`controlPoints` (`flags` alias)	`control_points` (`flags` alias)	`Flags()` only	no facade	`controlPoints` (sync)
Register target	`runtime.registerTarget`	`runtime.register_target`	absent	absent	`client.identify`
Native typed getters	boolean / string / number / object	boolean / string / int / float / object	`Evaluate` only	boolean + string; others via `evaluate` or OF	boolean / string / number / object (sync)
Shutdown flushes client exposures	yes	yes	no — `Exposures().Flush` first	no — `exposures().flush()` first	yes (+ unload)
Env config	yes	yes	remote adapter	no	no

Wire paths

Method	Path	Who implements the client
`POST`	`/v1/flags/evaluate`	All five remote adapters
`POST`	`/v1/capture`	All five remote adapters
`POST`	`/v1/targets/register`	Node, Python, Web only

Auth: Authorization: Bearer <key>. The test server implements evaluate, capture, and /health — not /v1/targets/register.

Runtime compatibility notes

Node 2.1 is ESM, portable across Node / Bun / Deno (readEnv, no Buffer / bare process.env in src/). OpenFeature provider smoke on Deno is not asserted by CI.
Web targets browsers only. Suite runs on Bun + happy-dom. No server entry point.
CI “latest” / “stable” / “canary” cells float. Document minimums from manifests, not floating CI cells as support guarantees.
No mobile, iOS, Android, Rust, .NET, PHP, or Ruby packages under sdks/.

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Package and API index

Packages

OpenFeature pins

Env vars and config

Adapters (quick map)

Errors

Language gates (do not paper over)

Wire paths

Runtime compatibility notes

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Node

Python

Go

Java

Web

Compatibility

​Packages

​OpenFeature pins

​Env vars and config

​Adapters (quick map)

​Errors

​Language gates (do not paper over)

​Wire paths

​Runtime compatibility notes

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Node

Python

Go

Java

Web

Compatibility

Packages

OpenFeature pins

Env vars and config

Adapters (quick map)

Errors

Language gates (do not paper over)

Wire paths

Runtime compatibility notes

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