Open-source alternatives to Dollar

Radash is a TypeScript functional utility library designed for data transformation, validation, and workflow management. It provides a collection of typed helper functions to manipulate arrays, objects, and strings. The project features an asynchronous workflow toolkit for managing promises, retries, and concurrency limits, alongside a suite of boolean validators for verifying primitive types, objects, and promises. It also implements functional programming patterns such as function composition, partial application, and error-first response patterns. The library covers a broad surface of cap

Functional-Light-JS is a JavaScript functional programming library designed to implement functional patterns within JavaScript applications. It serves as a toolkit for declarative data processing, immutable data management, and the construction of complex logic through higher-order functions. The library focuses on a pragmatic implementation of functional programming, providing utilities for curried argument application and function composition. It emphasizes the use of pure functions to calculate state updates and manage application data without side effects. The project covers broad capabi

Remeda is a type-safe functional utility library for TypeScript designed for building data transformation pipelines. It provides a toolkit of helper functions for manipulating arrays and objects while maintaining strict type integrity throughout the process. The library is characterized by its support for both data-first and data-last calling styles. It utilizes lazy evaluation to process data collections, evaluating transformations only when the final result is requested to avoid creating intermediate collection copies. The toolkit covers collection manipulation, function composition, and t

This is a persistent data structure library for JavaScript that provides collections which prevent the direct mutation of objects and arrays. It serves as an immutable state management tool and functional programming utility, ensuring that data remains unchanged after creation to simplify change detection and state tracking. The library enables the maintenance of application state by producing new versions of data structures during updates. It focuses on efficient data comparison by checking actual content instead of memory references and supports a functional programming workflow to prevent

Returns is a functional programming library for Python that provides type-safe containers for managing state, error handling, and optionality. It serves as a monadic container library and a type-safe error handling framework, replacing traditional try-catch blocks and null checks with Result and Optional containers to treat exceptions as data. The project is distinguished by its use of a specialized Mypy static analysis plugin to validate functional pipelines and emulate higher kinded types. It provides mechanisms for isolating side effects through IO containers and offers a framework for typ

Just is a collection of JavaScript utility libraries designed for data manipulation, functional programming, performance optimization, statistical analysis, and string processing. It provides a set of tools for deep cloning, filtering, and transforming complex objects and arrays. The project is structured as a series of zero-dependency modules, allowing utilities to be used independently to minimize bundle size. It implements functional programming patterns including currying, piping, and partial application, and provides execution control through memoization, debouncing, and throttling. The

Sprig is a comprehensive library of helper functions designed to extend the Go text template engine. It provides a wide array of custom functions that can be injected into the engine to enable complex data manipulation and logic directly within templates. The project offers specialized capabilities for cryptography, including the generation of private keys, X.509 certificates, and secure password hashes. It also includes advanced logic extensions for semantic versioning comparison, ternary evaluations, and the resolution of environment variables from the host operating system. The library co

This project is an educational resource and a collection of instructional materials for performing data manipulation and statistical analysis using Python. It provides a comprehensive set of guides and code examples for using the Pandas, NumPy, and Matplotlib libraries to analyze structured data. The resource includes a dedicated guide for reshaping, cleaning, and aggregating tabular data and time series via Pandas, alongside a reference for high-performance vectorized operations and linear algebra using NumPy. It also features tutorials for creating publication-quality charts, distribution p

This is an interactive Python tutorial delivered as a collection of Jupyter notebooks. It is designed as a structured learning path for beginners, teaching fundamental language concepts through a sequence of lessons that combine explanatory text with runnable code cells and embedded practice exercises. Each notebook is a self-contained unit that introduces a topic, demonstrates it with a minimal code example, and then asks the learner to write code themselves, receiving immediate feedback from the browser-based execution environment. The curriculum is built on a progressive concept-stacking mo

Carp is a statically typed Lisp compiler that compiles Lisp-like syntax directly to C source code, enabling seamless integration with existing C libraries and low-level system programming. It manages memory deterministically at compile time using ownership tracking and linear types, eliminating garbage collection pauses and runtime overhead while ensuring type safety through an inferred static type system. The language distinguishes itself through compile-time macro expansion and metaprogramming capabilities, allowing code generation and transformation before final binary output. It enforces

Swift Algorithms is a library of sequence and collection algorithms for Swift, providing operations for splitting, cycling, combining, and sampling collections with lazy evaluation. It extends Swift's standard library with algorithms that work across all types conforming to Sequence and Collection protocols, enabling efficient data processing without intermediate storage. The library specializes in combinatorial enumeration, generating all possible permutations, combinations, and product sequences from collections for testing and exploration. It also includes utilities for splitting collectio

PureScript is a statically typed, purely functional programming language that compiles to JavaScript. It is designed as a cross-platform frontend language for building safe web applications, utilizing a static type system and a JavaScript compiler to ensure program correctness across browser and server environments. The language is distinguished by its emphasis on mathematical purity, featuring a robust type system with first-class support for monads. It provides a sophisticated toolset for static verification, including algebraic data types, type classes, and automatic type inference to reje

collect.js is a dependency-free JavaScript library that provides a fluent, chainable interface for manipulating arrays and objects. It mirrors the Laravel Collection API, offering a consistent set of methods for data transformation across JavaScript and Laravel backend environments. The library stores collection data as plain arrays internally and supports fluent method chaining, where each method returns a new collection instance. The library distinguishes itself by closely replicating the Laravel Collection API in JavaScript, mapping each PHP method to an equivalent JavaScript implementatio

Doctrine Collections is a PHP library that provides object-oriented abstractions for managing and manipulating groups of objects with array-like functionality. It wraps native PHP arrays in an object-oriented interface, enabling cleaner data manipulation through methods for filtering, mapping, and iteration. The library supports callback-driven transformation, applying a callback to every element and returning a new collection with the transformed values. It also enables criteria expression querying, allowing selection of matching elements by applying a criteria object with comparison express

This library is a collection of generic utilities for the Go programming language designed to simplify the manipulation of slices and maps. It provides a functional toolkit that enables developers to perform data transformations, such as filtering, mapping, and reducing, while maintaining strict type safety through the use of language-level generics. The project distinguishes itself by offering a dual approach to data processing that balances functional programming patterns with performance-oriented execution. It supports both immutable functional pipelines for predictable state transitions a

This project is a comprehensive programming tutorial and technical guide focused on the Java 8 language specification. It provides educational resources for implementing functional programming patterns, utilizing modern language syntax, and adopting updated API standards. The guide covers the transition to functional programming through the use of lambda expressions, method and constructor references, and functional interfaces. It also details the use of default interface methods to extend logic without breaking existing classes and the implementation of repeatable annotations. Additional co

Underscore is a JavaScript utility library providing a suite of functional programming and data manipulation helpers. It serves as a framework for transforming data collections, composing functions, managing objects, and performing precise data type validation without modifying core language prototypes. The project includes a functional programming toolkit designed to control function execution timing and behavior through techniques such as debouncing, throttling, and partial application. It also provides a dedicated object manipulation utility for cloning, merging, picking, and omitting prop

SwifterSwift is a collection of Swift extensions designed to reduce boilerplate code during the development of iOS and macOS applications. It provides a library of pre-made utilities that extend the standard library and system frameworks to streamline data manipulation, system integration, and user interface optimization. The project provides specialized tools for a wide range of development tasks. This includes image processing and binary translation, text string manipulation, and complex data management for arrays, strings, and dictionaries. It also offers utilities for network request mana

r4ds is a data science curriculum and educational resource designed for mastering the R programming language. It provides a structured learning path for the end-to-end process of importing, tidying, transforming, and visualizing data. The project emphasizes a reproducible data science guide and a comprehensive curriculum for data wrangling. It includes specialized tutorials on the grammar of graphics for layered data visualization and technical publications created with Quarto that blend executable code with narrative prose. The material covers a broad range of analytical capabilities, inclu

Chrono is a Rust date and time library used for managing calendar dates, clock times, and timezone conversions. It functions as a high-precision timestamp tool and temporal data serializer for converting date and time objects into structured formats. The library includes a timezone conversion engine to translate timestamps between different geographical zones and manage local time configurations. Its broader capabilities cover date string formatting, high-precision timing, and the serialization of temporal data for database storage or network transmission.

Moment is a JavaScript date manipulation library used for parsing, validating, manipulating, and formatting dates and times. It provides a system for converting date strings into structured objects using the ISO 8601 standard or custom tokens. The library includes a timezone management tool for handling UTC offsets and geographic timezones, ensuring accurate date calculations across different regions. It features an internationalized date formatter and a relative time calculator to render timestamps as human-friendly durations adapted to various cultural locales and languages. The project co

Arrow is a Python date and time library that provides a simplified interface for creating and manipulating timestamps by wrapping the Python standard library. It serves as a tool for managing date objects, handling timezone offsets, and performing relative date calculations. The library is distinguished by its ability to humanize timestamps into natural language relative descriptions across multiple locales and parse human-readable time phrases back into precise date objects. It also features a specialized parser for converting ISO 8601 strings and custom formatted text into date objects. Br

Carbon is a Go library for semantic date and time calculations, formatting, and parsing. It provides a semantic interface to simplify temporal data handling and improve the readability of date and time manipulations. The library is distinguished by its support for multi-calendar date conversion, allowing transformations between Gregorian, Chinese Lunar, Persian, and Hebrew calendar systems. It also includes a localized temporal framework that uses ISO 639-1 codes to format dates and relative time differences across multiple language locales. Additional capabilities cover global time zone man

This project is a comprehensive date and time library designed for parsing, formatting, and calculating dates and times with high precision. It provides a multi-calendar system implementation that supports conversions between proleptic Gregorian, Julian, ISO week, and Tabular Islamic calendars. The library is distinguished by its high-precision time clocks and its implementation of the IANA time zone database. It tracks physical time using UTC, TAI, and GPS clocks to account for leap seconds and provides a system for managing geographic time zones and offsets based on IANA data. The capabili

is.js is a JavaScript validation library and data type checker. It provides a suite of utilities to verify whether variables are primitives, arrays, functions, or specific object types. The project allows for the implementation of custom validation logic and the use of naming namespaces to override default rules and regular expressions. It covers a broad range of validation capabilities, including numeric arithmetic properties, date and time analysis for relative and absolute ranges, and string format verification for patterns such as emails, URLs, and IP addresses. The library also includes

This project is a comprehensive JavaScript programming tutorial and language reference. It serves as a web development education resource providing instruction on modern language fundamentals, object-oriented design, and advanced asynchronous programming patterns. The resource functions as both a frontend development guide and a technical reference. It covers core language features such as closures, prototypes, promises, and typed arrays, while providing practical lessons on managing browser data and handling network requests. The content spans several key capability areas, including browser