# Efficient, Portable, Census-Polymorphic Choreographic Programming

arXiv: https://arxiv.org/abs/2412.02107 · HTML: https://mlsanity.com/paper/2412.02107/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 3 Dec 2024.

## Built on by (most cited first, 2 of 2)

- [Pact: A Choreographic Language for Agentic Ecosystems](https://mlsanity.com/paper/2605.03143/) (2026)
- [ETAS: An Effect-Typed Language for Agent Systems](https://mlsanity.com/paper/2607.17780/) (2026)

## Abstract (arXiv)

Choreographic programming (CP) is a paradigm for implementing distributed systems that uses a single global program to define the actions and interactions of all participants. Library-level CP implementations, like HasChor, integrate well with mainstream programming languages but have several limitations: Their conditionals require extra communication; they require specific host-language features (e.g., monads); and they lack support for programming patterns that are essential for implementing realistic distributed applications. We make three contributions to library-level CP to specifically address these challenges. First, we propose and formalize conclaves and multiply-located values, which enable efficient conditionals in library-level CP without redundant communication. Second, we propose end-point projection as dependency injection, a design pattern that enables library-level CP in host languages without support for monads. Third, we propose census polymorphism, a technique for abstracting over the number of participants in a choreography. We demonstrate these contributions via implementations in Haskell, Rust, and TypeScript.