fp-ts vs Ramda
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
A TypeScript library bringing common functional programming types like Option and Either.
Open source · MIT
A JavaScript utility library for writing functional-style code without changing your data.
The short answer
Choose fp-ts if you need…
- Developers already familiar with functional programming who want these patterns in TypeScript
- Teams using TypeScript with strict mode enabled, which the library is designed for
- Projects that need typed abstractions like Option and Either for error handling
- Developers maintaining existing codebases that already depend on fp-ts
Choose Ramda if you need…
- JavaScript developers who want to write functional-style data transformations
- Teams that prefer immutable data handling and small composable functions
- Developers building function pipelines from simpler functions
- Projects that can install an npm package and use modern JavaScript modules
Side-by-side
| fp-ts | Ramda | |
|---|---|---|
| Type | Library | Library |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 11.5k | 24.1k |
| Setup difficulty | Intermediate | Intermediate |
| How you get it | Install with a package manager | Install with a package manager |
| Main language | TypeScript | JavaScript |
| Last code update | 7 months ago | 25 days ago |
What each one is
fp-ts
fp-ts is a TypeScript library that provides common functional programming building blocks, such as Option, Either, IO, Task, and abstractions like Functor, Applicative, and Monad. It is aimed at developers who want to write code in a functional style with strong type checking. The README notes that it implements Higher Kinded Types, which TypeScript does not support natively. The README also announces that fp-ts is merging into the Effect-TS ecosystem, which it describes as the successor to fp-ts v2.
Ramda
Ramda is a JavaScript library of helper functions for transforming data in a functional style. Its functions are automatically curried and take the data as the last argument, so you can chain small functions into pipelines. It is designed so that it never mutates the data you pass in.
Best for
fp-ts
- Developers already familiar with functional programming who want these patterns in TypeScript
- Teams using TypeScript with strict mode enabled, which the library is designed for
- Projects that need typed abstractions like Option and Either for error handling
- Developers maintaining existing codebases that already depend on fp-ts
Ramda
- JavaScript developers who want to write functional-style data transformations
- Teams that prefer immutable data handling and small composable functions
- Developers building function pipelines from simpler functions
- Projects that can install an npm package and use modern JavaScript modules
Strengths
fp-ts
- Includes widely used types and abstractions modeled on Haskell, PureScript, and Scala
- Implements Higher Kinded Types, a feature TypeScript lacks natively
- Documented API reference, learning resources, and an ecosystem page
Ramda
- Functions are automatically curried, which makes building new functions from old ones straightforward
- Data is supplied last in arguments, which the README says supports pipeline-style code
- Published as an npm package with browser, Deno and ES module builds
Not ideal for
fp-ts
- Beginners learning functional programming, because the docs assume you already know FP concepts
- New projects that want the newest direction, since the README points users to Effect-TS as the successor to fp-ts v2
- Projects using TypeScript older than 3.5, since version 2.0.x requires TypeScript 3.5 or newer
Ramda
- Developers who want a general-purpose toolkit mixing paradigms; the README says Ramda is focused on functional style specifically
- Beginners who are not yet comfortable with functions as values, since currying and composition take practice to read
- Projects that need the library to enforce immutability; the README says Ramda does not enforce it
Trade-offs
fp-ts
- The README announces a merge into Effect-TS, so the long-term direction of this project is changing
- Teaching functional programming is out of scope, so beginners will need outside resources
- Multiple installed versions can cause tsc to hang, so dependency management needs care
Ramda
- Functional style with currying can be harder to read for developers new to the approach
- The README notes that using the 'latest' CDN link risks breaking changes, so versions should be pinned
- Tree-shaking results depend on the bundler and setup, according to the README
Getting started
fp-ts
Install the stable version
npm install fp-tsCheck installed versions
npm ls fp-tsFrequently asked questions
What is the difference between fp-ts and Ramda?
fp-ts: A TypeScript library bringing common functional programming types like Option and Either. Ramda: A JavaScript utility library for writing functional-style code without changing your data. fp-ts suits developers already familiar with functional programming who want these patterns in typescript, while Ramda suits javascript developers who want to write functional-style data transformations.
Are fp-ts and Ramda free?
fp-ts: Free and open source. Ramda: Free and open source.
Is fp-ts or Ramda more popular?
Ramda has more GitHub stars (24.1k) than fp-ts (11.5k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to fp-ts and Ramda?
Other options people compare them with include Effect, Immutable.js.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.