Open-source alternatives to Change Case

type-fest is a library of reusable utility types for performing complex transformations and validations on objects, arrays, strings, and numeric ranges in TypeScript. It provides a collection of type definitions designed to handle advanced structural changes and constraints. The project distinguishes itself by offering specialized logic for string literal processing, such as casing transformations and pattern-based modifications, and type-level arithmetic for calculating numeric ranges and absolute values. It also includes utilities for enforcing deep immutability, ensuring union mutual exclu

Rockstar is an esoteric programming language whose syntax is inspired by 1980s hard rock and heavy metal lyrics, making programs read like song lyrics. It uses poetic number literals, where the length of each word in a phrase is parsed as a decimal digit to initialize numeric variables, and pronoun-based variable references, where words like "it" and "they" resolve to the most recently assigned or compared variable at runtime. The language can be compiled to WebAssembly and run inside a web page for in-browser code execution. The language distinguishes itself through a lyric-driven parsing sy

Dollar is a functional programming library for Swift that provides a comprehensive toolkit for collection manipulation, string processing, mathematical calculations, and date and time management. It serves as a utility suite for filtering, aggregating, and restructuring arrays and dictionaries. The project implements functional programming patterns such as currying, memoization, and function composition. It also features a chainable wrapper interface that allows multiple data transformations to be applied sequentially before extracting a final result. The library covers a wide range of capab

Go Package of validators and sanitizers for strings, numerics, slices and structs

sqlean is a collection of SQLite extension libraries implemented as C-based shared libraries. It provides a suite of additional scalar and table-valued functions that expand the native capabilities of the SQLite database engine. The project provides specialized toolsets for cryptography, advanced mathematics, networking, and filesystem access. These include binary hashing and encoding, statistical analysis, IP address validation, and the ability to map CSV files or filesystem paths as virtual tables. The library also includes comprehensive text processing tools such as regular expressions, f

30 Seconds of Python is a curated collection of short, reusable Python code snippets designed for quick reference and immediate reuse. It provides an interactive browser that lets you explore snippets organized by tags, search across names and descriptions, and copy code to your clipboard with a single click. The collection covers a broad range of common programming tasks, including list and dictionary operations, string formatting and manipulation, date and time calculations, and color format conversion. It also includes utilities for data transformation, such as converting between case styl

Micrometer is a dimensional metrics library and application metrics facade that provides a vendor-neutral interface for recording performance data. It decouples application instrumentation from specific observability backends, allowing the recording of counters, gauges, and timers using key-value tags for granular analysis. The project features a system of backend adapters that transform and route instrumented data to various external monitoring tools. This includes name normalization to ensure portability across different monitoring systems and the ability to map dimensional data to hierarch

This project is a comprehensive collection of C++ libraries and toolkits providing reference implementations for data structures, graph algorithms, and bitwise logic. It serves as a C++ algorithm reference containing over 180 solved coding problems and a specialized toolkit for competitive programming. The repository distinguishes itself through extensive low-level bit manipulation libraries for parity checks, endianness detection, and XOR-based logic. It also provides a wide array of reference solutions for complex algorithmic challenges involving backtracking, graph theory, and dynamic prog

OpenRewrite is an automated refactoring engine and source-to-source migration framework. It uses a lossless semantic tree parser to represent source code as type-aware trees that preserve original whitespace and formatting, enabling precise and deterministic modifications. The project utilizes a declarative refactoring pipeline where sequences of transformations are defined in YAML to resolve breaking changes and technical debt. It features type-aware pattern matching and cross-language model mapping to apply similar refactoring patterns across different programming languages. The framework

Plop is a template-based code generator and interactive command-line scaffolding tool. It functions as a file system automation engine that uses a pipeline of prompt-driven tasks and regular expression replacements to generate and modify codebase structures. The framework combines Handlebars templates with interactive terminal prompts to automate boilerplate code generation. It allows for the enforcement of codebase patterns through shared generators and provides the ability to embed the engine into custom command-line tools. The system covers the creation of project files from templates and

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

This project is a centralized repository of XML definitions used to automate the formatting of bibliographic citations and references for scholarly publications. It functions as a declarative citation framework that maps bibliographic metadata to visual output using a schema-driven system rather than procedural code. The library provides a comprehensive collection of standardized formatting rules and locale files used to render academic citations according to specific journal or publisher requirements. It includes a bibliographic localization framework that adapts dates, punctuation, and term

RxGo is a functional reactive programming library and an implementation of ReactiveX for the Go language. It serves as an asynchronous stream processing toolkit designed to coordinate event-based programs and data flows using the observable pattern. The library enables the construction of asynchronous processing pipelines that transform, filter, and combine event sequences. It distinguishes itself through the use of functional operators to compose these pipelines and provides mechanisms for managing concurrent execution. The toolkit covers a broad range of stream orchestration capabilities,

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

MadelineProto is an asynchronous PHP library that provides a programmatic interface for interacting with the Telegram API using the MTProto protocol, the same protocol used by official Telegram clients. It functions as both a Telegram bot SDK and a userbot automation library, enabling PHP applications to connect to Telegram as either a bot account or a regular user account, sending and receiving messages, media, and other data directly without relying on the Bot API intermediary. The library is built on an event-driven architecture with Amp v3 fiber-based concurrency, allowing for non-blockin

This project is an object persistence library and data mapper abstraction layer. It provides a set of shared interfaces and base classes designed to decouple domain logic from specific object mapper implementations, separating the business domain layer from the underlying data access implementation. The library includes a database schema management and migration tool for defining, versioning, and deploying incremental updates to database structures across different environments. It also functions as a document database mapper, translating object states into structured document formats for sto

This project is a technical study guide and architectural analysis of the Vue.js framework. It serves as an educational resource for understanding the implementation of a reactive framework, providing source code analysis and architectural visualizations to explain the internal workings of the Model-View-ViewModel pattern. The project focuses on the mechanics of reactive framework implementation, specifically how dependency tracking, getters, and setters are used to synchronize state with a user interface. It includes detailed examinations of the virtual DOM and the process of reconciling ele

Lodash is a JavaScript utility library and data manipulation toolkit. It provides a collection of modular functions for transforming, filtering, and validating arrays, objects, strings, and numbers. The project functions as a functional programming toolkit, offering capabilities for function composition, currying, and lazy evaluation. It includes mechanisms for execution control, such as debouncing and throttling, to manage the timing and frequency of function invocations. The library covers a broad surface of data operations, including deep cloning and merging of complex nested structures,

This project is a sample library and implementation guide for using RxJava to manage asynchronous data streams and concurrent tasks in Android applications. It provides a collection of reference implementations for reactive programming, focusing on functional operators to transform and combine asynchronous data flows. The library demonstrates specific Android architectural patterns, such as implementing decoupled event buses for component communication and coordinating parallel network requests. It includes concrete examples of mobile-specific patterns including search input debouncing, list

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

Cats is a Scala functional programming library and type class library designed to implement algebraic patterns and functional abstractions. It provides a standardized set of interfaces and a modular toolkit of functional wrappers and containers to enable ad-hoc polymorphism and generic programming across disparate types. The project serves as a functional abstraction standard, offering a monad transformer suite to compose nested effectful contexts and handle multiple computational side effects within a single pipeline. It further enables the construction of embedded domain-specific languages

Bacon.js is a JavaScript functional reactive programming library used for coordinating complex asynchronous data flows. It functions as an observable event stream framework and an asynchronous data flow orchestrator, allowing developers to model events as declarative streams and properties. The library distinguishes itself through its ability to manage reactive state and synchronize timing across multiple sources. It provides specialized mechanisms for atomic state synchronization to prevent glitches in derived properties and offers advanced coordination strategies such as asynchronous stream

Awesome Print is a Ruby pretty printer and object inspector designed to visualize data structures through indentation and ANSI colors. It serves as a formatter for interactive shells and a utility for analyzing internal object states. The project features a plugin system for defining custom formatting rules for specific object types and supports global preference loading via a configuration file in the home directory. It can return formatted ASCII strings instead of printing directly to the console. Capabilities extend to rendering formatted object structures within web templates and writing

imove is a JavaScript workflow orchestration library and functional pipeline framework. It operates as a graph-based logic engine that executes modular functional units by traversing a directed graph of nodes and edges. The system functions as a visual logic flow mapper, translating graphical flowcharts into executable program sequences to manage business logic visually. It allows for the creation of reusable logic nodes that can be instantiated multiple times with unique parameters. The library provides an environment-agnostic runtime to execute the same orchestrated functional sequences ac

Ramda is a functional JavaScript standard library and toolset for immutable data transformation and composition. It provides a comprehensive suite of pure utility functions designed to enable declarative data processing pipelines. The library is distinguished by its use of automatic function currying and a data-last argument order. These design patterns allow multi-argument functions to be partially applied, simplifying the construction of processing chains where data is passed through a sequence of operations. The toolkit covers broad data manipulation capabilities, including list processin

RxJava is a reactive stream processing framework and JVM reactive extensions library. It serves as an asynchronous dataflow orchestrator used to compose event-based programs by transforming, combining, and consuming real-time data flows on the Java Virtual Machine. The project distinguishes itself through integrated backpressure flow control, which manages the emission rate between producers and consumers to prevent memory exhaustion. It further provides mechanisms for concurrent thread management and parallel data processing to offload blocking operations and maintain application responsiven

This project is a command-line processor designed for the parsing, filtering, and transformation of structured data streams. It functions as a declarative programming environment that treats data as immutable streams, allowing users to perform complex structural modifications through the composition of small, reusable functions. By utilizing a recursive tree traversal engine, the system enables the navigation, inspection, and modification of deeply nested hierarchical data structures. The engine distinguishes itself through a stream-oriented architecture that processes input records one by on