Open ecosystem

Jev’s launch week produced a flood of GitHub projects. We verified the existence, license, and stars of these 24 repositories one by one via the GitHub API (2026-09-22) and grouped them by category.

Three ground rules

1. “Official” is reserved for first-party repos under the typesafe-ai org; everything else is labeled a community integration
2. Inspired replicas (SemIf, kev, NanoJev) are not open-weight Jev — Jev’s weights are not open
3. Stars are an attention snapshot, not a quality seal; be extra careful with same-day batch submissions

Stars and repo status as of 2026-09-22 (verified via GitHub API) and reflect attention only. “Official” is reserved for first-party repos under the typesafe-ai org; replicas reimplement the interface idea — Jev’s weights are not open source.

Project	Category	Relationship	License	★	Summary
typesafe-ai/skills	Official SDKs & tools	Official	MIT	1,472	Official agent skills teaching coding agents such as Claude Code and Codex how to call the System One API.
typesafe-ai/system-one-adapter-python	Official SDKs & tools	Official	MIT	226	Official adapter that emulates TypeSafeClient on top of ordinary LLM APIs for A/B testing or fallback.
typesafe-ai/typesafe-sdk-js	Official SDKs & tools	Official	MIT	206	Official TypeScript/JavaScript SDK (npm package @typesafe-ai/sdk) with inferred answer types, built-in retries and error classes.
typesafe-ai/typesafe-sdk-python	Official SDKs & tools	Official	MIT	178	Official Python SDK (pip package typesafe-sdk, Python >= 3.10) with sync/async clients and Choice/Score/Noul types; reads TYPESAFE_API_KEY by default.
browser-use/jev-ultrafast	Browser / computer use	Community integration	MIT	14,820	Browser Use's fast web agent: Jev picks each action and target element while a small LLM only types when needed. The most-starred Jev project of launch week.
jkudish/jev-browser	Browser / computer use	Community integration	MIT	221	Browser automation driven by Jev.
tamaratran/fast-jev-compaction	Coding agent plugins	Community integration	MIT	5,845	Claude Code plugin that replaces compaction summaries with Jev decisions on every past tool call; kept content stays verbatim. The approach is debated in the community.
devagrawal09/jev-review	Coding agent plugins	Community integration	MIT	460	A staged code-review workflow with a local dashboard.
gargpratyush/jev-router	Coding agent plugins	Community integration	MIT	299	Claude Code plugin that routes each task to the cheapest sufficient model.
jkudish/jev-mcp	MCP & agent skills	Community integration	MIT	213	MCP server exposing typed judgments (screening, filtering, ranking) as agent tools.
itsmostafa/typesafe-mcp	MCP & agent skills	Community integration	MIT	187	MCP connector giving agents direct access to Jev.
yusukebe/hono-jev-router	Routing & gateways	Community integration	MIT	45	Hono middleware that routes HTTP requests by meaning.
superagents-lab/jev-search	Data / SQL / retrieval	Community integration	MIT	363	Web search where Jev picks sources, interprets queries, and ranks relevance (built on Search1API).
realZachi/pg-jev	Data / SQL / retrieval	Community integration	unknown	272	A PostgreSQL extension for asking plain-language questions over table rows. Its license is not recognized by GitHub as a standard open-source license.
sutro-sh/jev-align	Data / SQL / retrieval	Community integration	Apache-2.0	258	Calibrates Jev judgment functions from human feedback using GEPA.
jerryjliu/docjev	Data / SQL / retrieval	Community integration	Apache-2.0	165	From LlamaIndex: fast document classification and sub-document boundary detection with Jev.
leepokai/jev-guard	Safety & moderation	Community integration	MIT	18	A safety gate for coding agents: risk-scores every tool call as deny/ask/allow and flags prompt injection across many coding assistants.
win4r/jev-security-scan	Safety & moderation	Community integration	MIT	9	Reviews agent skills and MCP code for suspicious behavior using Jev (Chinese-language project).
TheoLeeCJ/SemIf	Open replicas	Inspired replica	MIT	2,935	An inspired open-source reimplementation of the 'semantic if' interface on open models, runnable on a single RTX 3090. Formerly OpenJev; the author states it is independent of TypeSafe. Not the Jev weights.
jaredpalmer/kev	Open replicas	Inspired replica	Apache-2.0	1,968	A tiny Jev-like decision-model family built on Qwen3.5 that you can train and run yourself.
TianyuCodings/NanoJev	Open replicas	Inspired replica	MIT	1,751	A 0.6B-parameter Jev replica with parallel decisions, dynamic candidates, and an end-to-end training pipeline. Community project, unrelated to TypeSafe.
jarrodwatts/jev-trader	Trading (research only)	Community integration	MIT	1,740	Makes one buy/sell decision per Monad block (dry-run by default). Research only — not investment advice; live trading carries real risk.
yibie/awesome-jev	Curated lists	Community integration	unknown	881	A curated English list of hundreds of projects and discussions across 13 categories; the author warns that same-day batch submissions are unvetted.
yzfly/awesome-jev-zh	Curated lists	Community integration	CC0-1.0	52	A Chinese curated list of official resources, apps, agent tooling, and replicas, with a Chinese quick-start guide.

Using the table

• Adopting an SDK: start in “Official SDKs & tools”; the skills repo teaches Claude Code / Codex-style agents to call the API correctly
• Building agents: the MCP servers expose judgments as tools; the guard projects implement tool approval (see Tool approval)
• Local experiments: replicas run a “Jev-style” interface on consumer GPUs — great for understanding the concept, never a basis for extrapolating Jev’s own production behavior

Submitting projects

This table follows our verification policy: the repo exists, the README matches the description, and the license is confirmed. Report problems with a project to its original repository; to correct this table or recommend a project, email contact@typesafe-jev.com.

Related pages

Video tutorials · Open-replica video roundup (Sam Witteveen, title verified) · Use cases