A workflow engine where the graph is deterministic, not your code

What it does Conductor is a durable workflow engine originally built at Netflix and now maintained by Orkes. It orchestrates long-running processes across microservices and AI agents by persisting every step and surviving crashes with configurable retries. Workers can be written in Java, Python, Go, JavaScript, C#, Ruby, or Rust, while the orchestration graph itself stays deterministic through declarative JSON.

The interesting bit Most workflow frameworks force your business logic to be deterministic so they can replay it; Conductor flips the burden and makes the engine deterministic instead. That means your worker code can use any library or blocking I/O without SDK gymnastics, and if an AI agent crashes on iteration twelve, it simply resumes at iteration twelve. The README even shows an autonomous agent built from DO_WHILE, LLM_CHAT_COMPLETE, and CALL_MCP_TOOL tasks, with LLMs generating JSON workflow definitions that Conductor executes immediately.

Key highlights

• Durable execution with full replayability: restart from the beginning, rerun any task, or retry just the failed step
• Native AI agent primitives: 14+ LLM providers, MCP tool calling, function calling, human-in-the-loop approval, and vector databases for RAG
• Polyglot workers across seven languages, though Ruby and Rust SDKs are still incubating
• Self-hosted under Apache 2.0 with five persistence backends and six message brokers
• Horizontal scaling to billions of executions, with cited production use at Netflix, Tesla, LinkedIn, and J.P. Morgan

Caveats

• Ruby and Rust SDKs are marked incubating
• The UI and full source build require Node 18 alongside the Java 21 runtime
• Backend flexibility is wide but finicky: you must pair a persistence store with a specific search index version

Verdict Teams running long-lived, failure-prone processes across multiple languages—or building autonomous AI agents that need to survive crashes—should evaluate this. If you just need a lightweight cron wrapper or a simple state machine, it is probably overkill.