Top 5 Functional Programming Languages To Know In 2023

Functional programming is one of the most trending topics in the present tech world. But, the interesting fact is that this efficient programming approach has been around for decades but the lack of information about it resulted in less discussion about it.

However, as the modern world is using effective resources to learn and use this practice to the fullest, it is significantly improving the software development scenario. So, we will be focusing on a brief introduction to this method and the top functional programming languages that you should know in 2023 to excel in your tech business.

What Is Functional Programming?

Functional programming is the practice of using pure functions to perform necessary operations in the application. You already know that functions are organized sets of instructions that are properly grouped to achieve specific outcomes and the best part about using pure functions is that they do not interact with outside elements and always return the same output, given the same input.

Unlike object-oriented programming, in functional programming, pure functions are not allowed to change their state. Hence, it becomes a great choice for concurrency as there is no shared state between functions.

Why Do Programmers Like Functional Programming?

Functional programming is a highly useful practice in data analysis and machine learning. Programmers like this approach for the following reasons.

  • It involves higher-order functions.
  • It ensures that there are no nulls.
  • It involves immutable data structures.
  • It has no exceptions for error handling.
  • It comes with function composition operators.
  • It provides pattern-matching capabilities.

These advantages or benefits are more developer-centric and people who have less knowledge about coding may face difficulties in figuring these out. So, let’s see what the overall advantages of functional programming are.

Advantages of Functional Programming

Functional programming provides a number of advantages that are mentioned below.

  • It enables you to perform complex operations with shorter code.
  • It allows you to work with small modular portions of the application, making it easier to deal with.
  • It provides you with easy debugging facilities.
  • It effectively improves the maintainability of the code.
  • It offers you efficient parallel programming capabilities.
  • It significantly improves the readability of the code.

What Is A Functional Programming Language?

Functional programming is a bit different from traditional object-oriented programming. It is basically a programming paradigm that can be described as a pattern-solving problem in computer science.

As we previously discussed, functional programming makes you write code in pure functions. This method is a declarative programming paradigm that includes functions as trees of expression mapping values to other values.

Now, let’s focus on the top functional programming languages that you should know in 2023 to perform efficient functional programming in your business.

Top 5 Functional Programming Languages

1. Elixir

Elixir is a highly popular programming language that is used for functional, general-purpose, and concurrent programming requirements. It was created by Jose Valim who had the goal of creating a programming language that can be used for large-scale sites and apps. It runs on the BEAM virtual machine and has gained popularity for its magnificent sustainability to build fault-tolerant, low-latency, and distributed applications.

It is an extremely powerful language as it is built on top of Erlang and makes the best use of the features of Erlang, Ruby, and Clojure. Due to its advantages, it is used by famous companies like Discord, Pinterest, PagerDuty, Inverse, Bleacher Report, The Outline, and many more that serve millions of users concurrently. Now, let’s take a look at its pros and cons.


  • It efficiently combines all the best features of Erlang, Ruby, and Clojure programming languages.
  • It is a high-concurrency and low-latency programming language.
  • It enables you to create highly concurrent and scalable applications that are also extremely fault-tolerant.
  • It can be extended to make developers define their own constructs as and when they need them.
  • It is suitable for applications that have to process high loads in millions of requests.
  • It supports immutability which makes it a perfect choice for multi-threaded applications.


  • It is difficult to test, especially to perform unit tests on elixir apps.
  • Though the Elixir apps have overall high reliability, it is quite difficult to write code in Elixir rather than in other high-level languages.
  • As it is an open-source language, you can get support only from the community forums that are still in the early stages of growth.

2. Clojure

Besides being a popular general-purpose language, Clojure is a useful dynamic and functional dialect of the Lisp programming language on the Java platform. It comes with immutable and persistent data structures, provides complete compatibility with Java Virtual Machine, and also allows developers to manage identity and states explicitly, helping developers a lot in creating concurrent and fast programs.

This language was created by Rich Hickey who had the goal to create a modern Lisp for functional programming. Along with supporting functions as first-class objects, a macro system, and a read-eval-print loop, it also supports recursion, lazy sequences, higher-order functions, and a reactive agent system. Though its primary platform is Java, other target implementations also exist.

Famous global companies like Walmart, Netflix, LinkedIn, Cisco, Salesforce, Circle CI, Puppet, Chartbeat, Boeing, Atlassian, and many others use this functional programming language due to its amazing features. Its pros and cons are these -


  • It gives you easy access to the Java framework.
  • It runs on the Java Virtual Machine which is a globally accepted environment.
  • Despite being a compiled language, it also supports most of the features of interpreted development.
  • It does not have a lot of syntactic sugar.
  • As it borrows good design/structure from other languages like Lisps, you get to use their advantages too.
  • It has an immutable data structure that helps in multi-threaded programming.


  • As the Clojure stack traces are huge, they are difficult to debug.
  • It has a lack of explicit types.
  • It does not come with a straightforward exception-handling mechanism.
  • It needs you to go through a steep learning curve.
  • It comes with powerful macros but their syntax is ugly.

3. Erlang

We have already mentioned the name of Erlang but it is such a useful language that it has taken a position among the top ones in our list here.

This general-purpose functional programming language and garbage-collected runtime system acquires huge popularity due to its capabilities around concurrency, distribution, and fault tolerance. It is a great choice for building messaging or chatting applications, distributed, real-time & concurrent systems like telecommunications, servers, database applications, high-available systems, and even blockchain apps. One of the largest examples of insanely popular applications built using this language is WhatsApp.

Erlang was developed by Joe Armstrong, Robert Virding, And Make Williams in 1986. Since then, it has gained immense popularity and is used by various top-level companies such as Facebook, Goldman Sachs, Samsung, Mitel, BT Mobile, RabbitMQ, and many more. It is used interchangeably with Erlang/OTP or Open Telecom Platform, which is a collection of useful libraries, tools, and middleware which are written in Erlang and it is an important part of the Erlang open-source distribution.

Now, let’s dive into its pros and cons that help people from different industries to decide if it is a good choice for them.


  • As it comes with a small set of syntax primitives, it remains simple for everyone.
  • It provides fully functional support for pure functions and higher-order functions.
  • It comes with well-documented libraries.
  • It is a process-oriented language and uses lightweight processes that communicate with each other via messages.
  • It has a well-established community of pro developers and is actively developing and making effective collaborations.
  • It offers you an automated storage management system and the garbage collection is implemented on a per-process basis, resulting in building highly responsive applications.
  • It lets you build highly scalable, concurrent, and reliable applications.


  • As it is dynamically typed, compile-time checking is not possible for it.
  • As it has a lack of a proper package manager, it can be cumbersome to deploy Erlang applications.

4. Haskell

This general-purpose, statically typed language Haskell is a purely functional programming language that offers type inference and lazy evaluation. It is older than Java and has turned out to be a pathfinder for many advanced features in programming languages. Probably for its immense popularity for such a long time, Haskell is often considered the “mother” of all functional programming languages.

As it comes with a compiler that is great at optimization, it is used for developing highly performant applications. Besides that, it is widely used in different fields like research, academia, and industrial applications. Being a purely functional language, its functions have no side effects.

It comes with many useful features like lambda expressions, lazy evaluation, type classes, pattern matching, list comprehension, and type polymorphism. Due to its awesome features, it is used for developing worldwide renowned applications like Cryptol, Pandoc, GHC, Target, Agda, Cardano Blockchain platform, and many more. So, let’s check out the pros and cons that make it so popular.


  • It easily handles chains of functions with lazy loading.
  • As it is an open-source language, it comes with a lot of community-created packages or libraries that are easily available to use.
  • Its type can be depicted bidirectionally.
  • As it contains several useful concurrency primitives, it is a great choice for concurrent multithreaded programming.
  • It has a highly expressive and concise syntax.
  • As it is a statically typed compile-type language, it throws a compile error in case of incorrect syntax, and it helps a lot in programming.


  • It needs you to go through a steep learning curve.
  • It comes with mysterious-looking programs that make it a bit difficult to understand.
  • It is not a good choice for normal web applications or real-time applications as it is more suitable for concurrent and scalable applications.

5. Scala

Despite not being functional, Scala makes it to this list because of efficiently supporting functional programming and object-oriented programming. It remarkably combines OOP and functional programming in one concise, single-packaged, high-level language.

This modern, multi-paradigm programming language supports Java Virtual Machines and JavaScript runtimes, allowing both strict type checking of statically typed language and allowing Scala to use and improve the existing ecosystem of libraries.

This extensible, statically-typed functional programming language is fully interoperable with Java, and its functional level context supports many features of standard ML, scheme, and Haskell that also include higher-order types, lazy evaluation, pattern matching, immutability, and type system that further supports raw strings, algebraic data types, and optional parameters.

The popularity of this language has made it a prominent choice for globally renowned companies like The New York Times, Foursquare, Airbnb, Firebase, Twitter, SoundCloud, LinkedIn, Verizon, Coursera, Apple, Walmart, and so on. Now, let’s take a look at its pros and cons to understand it better.


  • It remarkably supports popular IDEs.
  • It can be seamlessly interoperated with Java.
  • It allows you to perform fully functional programming with functions as first-class objects that can be called, assigned, or passed to another function.
  • Its objects are inherently immutable and that makes them a great choice for concurrent programming.
  • Its statically typed features help in type inference and check the type errors at compile time.
  • It is very easy to learn and adapt.


  • As it presently has a limited developer pool, the community forums and support are also limited.
  • As it is a hybrid of object-oriented programming and functional programming, it becomes a bit difficult for people to understand its information.


This article clearly tells you how important it is to make the best use of functional programming to improve your tech business. Here you also get an idea about the 5 best functional programming languages that offer you amazing features. So, we recommend you to carefully go through the article to choose the best one for your requirements.

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