duplexify

Turns writeable and readable streams into a single duplex stream.

DecliningOpen SourceLow lock-in

Pricing

Free tier

Flat rate

Adoption

Cooling

License

Open Source

Data freshness

Aging · Jun 8, 2026

Overview

What is duplexify?

Duplexify is a Node.js library that allows developers to combine two separate streams, one writable and the other readable, into a single duplex stream. This simplifies handling of complex data flows in applications using Node.js streams.

Key differentiator

Duplexify stands out as a lightweight and efficient solution for combining writable and readable streams into a single duplex stream, offering simplicity in managing complex data flows within Node.js applications.

Capability profile

Capability Radar

Ease of StartEcosystemValueMaturityFlexibilityScale Ready

Honest assessment

Strengths & Weaknesses

↑ Strengths

Combines writable and readable streams into a single duplex stream.medium

Simplifies complex data flow management in Node.js applications.medium

↓ Weaknesses

Limited documentation and exampleshigh

The official documentation lacks detailed usage scenarios and practical examples for complex stream operations.

Narrow focus limits versatilitymedium

Duplexify is specifically tailored to work with Node.js streams, limiting its application in broader contexts or with other data handling libraries.

Small community and slow issue resolutionhigh

The project has a relatively small contributor base which can lead to slower response times for bug fixes and feature requests.

Fit analysis

Who is it for?

✓ Best for

Node.js developers who need to manage complex data flows involving both input and output streams.

Projects requiring the integration of multiple streaming components into a single, unified interface.

✕ Not a fit for

Developers working with non-Node.js environments where stream handling is not required.

Applications that do not involve complex data flow management or require simpler stream operations.

Cost structure

Pricing

Free Tier

Available

Open source — free to use

Starts at

$0

Model

Flat rate

Enterprise

None

Performance benchmarks

How Fast Is It?

Ecosystem

Relationships

Next step

Get Started with duplexify

Step-by-step setup guide with code examples and common gotchas.

View Setup Guide →