Companies

OpenProse

prose.md

OpenProse builds open-source declarative infrastructure for reliable, long-running AI agent workflows.

HQSan Francisco, California, United States
Employees1-50
Jobs checked 2m ago
Developer ToolsAI InfrastructureOpen Source

About

OpenProse builds open-source infrastructure for long-running AI work: a declarative Markdown-based language and the Reactor runtime for reliable agent workflows. It targets software developers building repeatable multi-agent systems, differentiating through declarative contracts, reactive orchestration, portability, and an MIT-licensed open-source foundation.

Market

OpenProse competes in the open-source AI-agent orchestration and workflow-automation infrastructure market. It positions itself around reliable long-running AI work rather than one-off agent scripts, differentiating through Markdown contracts, declarative desired-state reconciliation, optional imperative ProseScript control, and a dedicated Reactor runtime.

Target Customers

OpenProse is aimed at software developers and technical teams building repeatable, reliable, long-running multi-agent workflows. Likely buyers are engineering, AI-platform, and automation leads at startups and other organizations with recurring software-development, go-to-market, or operations workflows.

At a Glance

Problem

OpenProse addresses the reliability gap in long-running AI-agent work. Conventional agent workflows are often imperative scripts: users specify step one, step two, and step three, then manually wire dependencies and hope the run produces the intended result. As workflows become more complex, changes can require reworking the sequence and rerunning unchanged work. OpenProse’s economic proposition is to reduce wasted model execution and operator attention by making workflows repeatable, incremental, and auditable.

The clearest use case is running recurring business operations as standing AI responsibilities. OpenProse’s own marketing, go-to-market, and operations reportedly run on responsibilities for mention tracking, competitor intelligence, lead enrichment, outreach drafting, and market indices. These are ongoing jobs where the world changes incrementally and reliability matters more than a one-off agent demo.

Product / Service

OpenProse is an open-source declarative language and runtime for AI work. Users write familiar Markdown contracts in .prose.md files, declaring what a responsibility requires and what truth it maintains rather than prescribing every execution step. The system compiles those contracts into a dependency graph, uses Forme to wire compatible inputs and outputs, and runs them on a compatible agent harness such as Claude Code, Codex, OpenCode, or Pi. Reactor is the project’s recommended deterministic harness.

At runtime, Reactor maintains a world model, watches for changes, and re-renders only the facets whose inputs have moved, while memoizing agent sessions in a dependency graph. This is intended to make long-running workflows more reliable and portable, while durable traces, world-model state, and signed receipts provide an audit trail for decisions and execution.

Market

OpenProse competes in open-source AI-agent infrastructure, specifically the emerging category of programming languages and runtimes for reliable, long-running agent workflows. Its adjacent alternatives include LangChain, CrewAI, and AutoGen, which orchestrate agents externally, as well as BAML and DSPy, which provide other programming or orchestration layers. OpenProse differentiates itself by putting the workflow’s declarative contracts and dependency resolution inside the AI-session model rather than treating orchestration as an external configuration layer.

The company appears to be at an early commercialization stage. Y Combinator lists OpenProse as an active Spring 2026 company founded in 2026 with a three-person team in San Francisco, and a company profile reports $500,000 raised from Y Combinator. Its strongest disclosed traction is product usage: the company says its own marketing, GTM, and operations run on thirteen OpenProse responsibilities. No public revenue figure or customer revenue is established in the retrieved evidence, so it is more accurate to describe OpenProse as early-stage with revenue undisclosed than to assert definitively that it is pre-revenue.

Founders & Leadership

Dan BarrettFounder
Founder & CEO

Funding History

2026-01
Pre-Seed$500K

Y Combinator

Recent News

2026-07-31product
OpenProse, Inc. GitHub update

OpenProse’s public GitHub presence describes the product as a declarative language for standing AI work, using Markdown contracts to specify what should remain true. The repository ecosystem presents this as an actively developing open-source product.

2026-06-12product
The OpenProse VM

OpenProse published learning materials explaining its VM model, compilation and execution phases, the Prose Complete standard, and its FAQ. The documentation positions OpenProse as a programming language for AI sessions.

2026-06-07
Field Notes: OpenProse

OpenProse’s field-notes page describes a structured analysis of competitor framework releases, funding, and messaging changes. It also documents the company’s effort to run its own marketing, GTM, enrichment, and community operations as Prose programs.

2026-05-26
OpenProse: An open-source operating system for reliable long-running agents

Y Combinator profiled OpenProse as an active Spring 2026 company building open-source infrastructure for long-running AI work, combining a declarative language with a reactive harness/runtime for agent workflows.

2026-05-26
Genie Lessons from Genie Sessions: Prose as a Programming Language

The Y Combinator OpenProse profile lists this publication as a dated news item associated with the company. Its title presents Prose as a programming language emerging from agent or “Genie” sessions.

2026-04-30product
OpenProse official documentation: a declarative programming paradigm

OpenProse documentation explains the project as a paradigm in which users declare outcomes that should remain true rather than issuing imperative instructions. This reinforces the product’s contract-based approach to AI work.

2026-04-26
OpenProse: A Programming Language for AI Sessions

A DEV Community article covers OpenProse’s contract-based semantics, parallel execution, control flow, persistent agents, and pipelines. It characterizes the system as declarative orchestration in which contracts determine dependencies and execution order.

2026-04-24
OpenProse: LLM Virtual Machines — Columbus

An AI Tinkerers listing highlighted an OpenProse project or talk focused on LLM virtual machines in Columbus, with the event scheduled for May 4. This indicates community event and presentation activity around the project.

2026-04-03partnership
OpenProse integration with OpenAEON

OpenAEON documents OpenProse as a plugin integration that installs an OpenProse skill pack and a /prose slash command. The integration maps OpenProse programs to OpenAEON primitives such as spawned sessions, file operations, and web fetching.

2026-02-02
Deep Dive: Open PROSE (prose.md)

A video deep dive introduced OpenProse as a natural-language programming language implemented through Markdown files, covering concepts such as agents and models. It provides independent media coverage of the project’s approach.

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Business Model

OpenProse’s core language is free, MIT-licensed, and portable, so the available evidence does not show recurring license fees or paid plans. The reviewed sources identify funding from Y Combinator but do not document a separate commercial revenue stream.

Products

OpenProse declarative languageReactor deterministic runtime/harnessOpenProse coding-agent Skill

Tech Stack

Markdown-based declarative programmingOpenProse contracts (*.prose.md)ProseScript imperative plansReactor deterministic runtime/harnessDependency-injection frameworkEvent-driven runtimeAI-agent harnesses with session, file, and tool access

Competitors

LangGraph
CrewAI
Microsoft AutoGen
Temporal