LangServe is deprecated. Here's a framework-agnostic, open-source alternative.
LangServe is deprecated. Its official successor, LangGraph Platform, is LangGraph-centric — which means the recommended migration path ties your deployment to a single framework. FastAgentic is the alternative that doesn't: open-source, self-hosted, framework-agnostic, and multi-protocol.
Wrap any agent — PydanticAI, LangGraph, CrewAI, or LangChain — and expose it as REST + MCP + A2A simultaneously from a single decorator, with durable checkpoints, policy controls, and observability. No cloud lock-in.
| LangServe | FastAgentic | |
|---|---|---|
| Status | Deprecated | Actively developed, open-source |
| Frameworks | LangChain-centric | Framework-agnostic — PydanticAI, LangGraph, CrewAI, LangChain |
| Protocols | REST | REST + MCP + A2A, simultaneously, from one decorator |
| Hosting | Self-hosted (deprecated) | Self-hosted, open-source — no cloud lock-in |
| Durability | Not built in | Durable checkpoints on Redis, Postgres, or S3 |
| Governance | Not built in | Budgets, rate limits, RBAC, PII masking |
| Observability | Not built in | OpenTelemetry, Langfuse, Datadog |
Why LangServe users are moving
LangServe answered a specific question well: how do you put a LangChain Runnable behind a REST endpoint? That question has since broadened. Production agent teams now run more than one framework, need to expose agents to MCP clients and to other agents over A2A, and need durability and governance that LangServe never shipped. With LangServe deprecated, those teams need a destination that doesn't trade one form of lock-in for another.
The successor keeps you locked to one framework
LangServe's official successor is LangGraph Platform. It is LangGraph-centric, so adopting it makes LangGraph the center of gravity for your deployment. That's a reasonable choice if LangGraph is the only framework you will ever run — and a constraint if it isn't.
The managed alternatives trade framework lock-in for cloud lock-in
The other well-known options are managed hyperscaler services. Amazon Bedrock AgentCore Runtime is a managed, framework- and model-agnostic runtime that serves HTTP, MCP, and A2A — with cloud lock-in to AWS. Microsoft Foundry Agent Service exposes MCP, A2A, and OpenAPI with one-command deploy — with cloud lock-in to Azure. Both are credible; both put your runtime inside a single cloud.
What FastAgentic does instead
- Framework-agnostic — wrap agents built in PydanticAI, LangGraph, CrewAI, or LangChain, unchanged.
- Multi-protocol at once — one decorator emits a REST route, an MCP tool, and an A2A skill from the same definition, plus streaming.
- Durable checkpoints — resumable runs backed by Redis, Postgres, or S3.
- Policy controls — budgets, rate limits, RBAC, and PII masking.
- Observability — OpenTelemetry, Langfuse, and Datadog.
- Open-source and self-hosted — no cloud lock-in and no single-framework requirement.
For a deeper, feature-by-feature breakdown, see the full FastAgentic vs LangServe comparison, or read why teams pick FastAgentic.
Frequently asked
- Is LangServe deprecated?
- Yes. LangServe is deprecated. Its official successor is LangGraph Platform, which is LangGraph-centric — so migrating to it ties your deployment to a single framework.
- What should I use instead of LangServe?
- FastAgentic is an open-source, self-hosted, framework-agnostic alternative. You wrap any agent built in PydanticAI, LangGraph, CrewAI, or LangChain and expose it as REST + MCP + A2A at once via a single decorator, with durable checkpoints, policy controls, and observability — and no cloud lock-in.
- How is FastAgentic different from LangGraph Platform, Bedrock AgentCore, or Foundry Agent Service?
- LangGraph Platform is LangGraph-centric, so it carries framework lock-in. Amazon Bedrock AgentCore Runtime and Microsoft Foundry Agent Service are managed services that carry cloud lock-in to AWS and Azure respectively. FastAgentic is open-source and self-hosted, framework-agnostic, and multi-protocol, so it avoids both kinds of lock-in.
- Do I have to rewrite my agent to migrate off LangServe?
- No. FastAgentic wraps an existing agent as-is and exposes it over REST, MCP, and A2A from one decorator, so you keep your current framework code.
Migrating off LangServe?
Neul Labs — the team behind FastAgentic — takes on a limited number of consulting engagements each quarter. We help teams ship agents to production, fix broken LangGraph pipelines, and design governance for multi-tenant LLM platforms.