TheJudex | Free Backend Runtimes & Frameworks & Open Source Software

Free Limits & Commercial Threshold Matrix

Exact breakdown of quotas, credit card requirements, and commercial allowances before requiring an upgrade.

Tool	Model	Conditions	Free Tier Details	SSO Tax	Action
Deno	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Software de código abierto gratuito e ilimitado para uso comercial y personal bajo licencia MIT.	Standard	Try
OpenStarterKit	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Acceso completo a la base de código bajo licencia open source de por vida.	Standard	Try
Godot Engine	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Acceso completo e ilimitado al motor de juego sin coste ni restricciones comerciales.	Standard	Try
Socket.IO	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	100% Free and open source without commercial limits.	Standard	Try
AI SDK	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Uso ilimitado y gratuito del SDK de código abierto mediante gestores de paquetes estándar.	Standard	Try
Flutter	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Uso ilimitado y gratuito de todo el framework y herramientas de desarrollo sin restricciones comerciales ni requerimiento de tarjeta de crédito.	Standard	Try
Temporal	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Incluye $150 en créditos durante 90 días y opción de autoalojamiento ilimitado mediante la versión de código abierto.	Standard	Try
Project Jupyter	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	100% Free and open source without commercial limits.	Standard	Try
GNU	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	El sistema operativo GNU y todas sus herramientas y fuentes son completamente libres y gratuitos de manera indefinida.	Standard	Try
Bun	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	100% Free and open source without commercial limits.	Standard	Try
Appwrite	Freemium	No credit card requiredCommercial use allowedMonthly recurring quota reset	El plan gratuito en la nube incluye límites generosos para bases de datos, almacenamiento y ejecución de funciones sin necesidad de tarjeta de crédito.	Standard	Try
Medusa	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	El software central de código abierto es completamente gratuito para autohospedaje ilimitado.	Standard	Try
Brut	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	100% Free and open source without commercial limits.	Standard	Try
Unreal Engine	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Uso gratuito e indefinido para desarrollo, sujeto a una regalía del 5% únicamente cuando los ingresos comerciales superen el umbral establecido.	Standard	Try
Keycloak	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	100% Free and open source without commercial limits.	Standard	Try
Prisma	Freemium	No credit card requiredCommercial use allowedMonthly recurring quota reset	Plan gratuito disponible sin tarjeta de crédito con recursos básicos para desarrollo y pruebas.	Single Sign-On Tax (Enterprise SAML)	Try
PocketBase	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	PocketBase es completamente gratuito y de código abierto sin limitaciones de uso en su versión autohospedada.	Standard	Try
Backenly	Freemium	No credit card requiredCommercial use allowedMonthly recurring quota reset	Incluye esquemas básicos de PostgreSQL y límites de integración MCP gratuitos.	Standard	Try
Cove	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Acceso libre e indefinido al código fuente bajo licencia open source.	Standard	Try
Popkern	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Acceso completo y permanente a todo el código fuente y herramientas bajo licencia de código abierto.	Standard	Try
B2B SaaS Starter	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Proyecto de código abierto gratuito e ilimitado para uso comercial bajo licencia MIT.	Standard	Try
栖梧 Qiwu	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Acceso completo al código fuente bajo licencia MIT sin restricciones de uso ni límites de tiempo.	Standard	Try
Xano	Freemium	No credit card requiredCommercial use allowedMonthly recurring quota reset	Permanent free tier with monthly usage allowances.	Standard	Try
KeystoneJS	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Completamente open-source y gratuito de forma indefinida.	Standard	Try
Payload	Freemium	No credit card requiredCommercial use allowedMonthly recurring quota reset	Permanent free tier with monthly usage allowances.	Standard	Try
Hasura	Freemium	No credit card requiredCommercial use allowedMonthly recurring quota reset	El plan gratuito permanente incluye un desarrollador de supergráficos, modelos ilimitados a cualquier escala y observabilidad con retención de 15 minutos.	Single Sign-On Tax (Enterprise SAML)	Try
Strapi	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Edición comunitaria gratuita y de código abierto para autoalojamiento sin límites de registros ni endpoints.	Single Sign-On Tax (Enterprise SAML)	Try
PartyKit	Free	No credit card requiredCommercial use allowedMonthly recurring quota reset	Plano gratuito para pequeños proyectos con despliegue edge, aunque el almacenamiento se borra cada 24 horas.	Standard	Try
Perch	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	100% Free and open source without commercial limits.	Standard	Try
Seed	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	100% Free and open source without commercial limits.	Standard	Try
Maple	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	100% Free and open source without commercial limits.	Standard	Try
PyPI	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Uso completamente gratuito e ilimitado para descarga y publicación de paquetes de código abierto.	Standard	Try
Oqtane	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	100% Free and open source without commercial limits.	Standard	Try
instancez	Freemium	No credit card requiredCommercial use allowedMonthly recurring quota reset	Free to start for side projects with zero base monthly cost.	Standard	Try
ABP Platform	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	El framework de código abierto ABP se puede utilizar de forma indefinida sin coste alguno para proyectos comerciales y personales.	Standard	Try
Deepnote	Freemium	No credit card requiredCommercial use allowedMonthly recurring quota reset	Permanent free tier with monthly usage allowances.	Single Sign-On Tax (Enterprise SAML)	Try
NativeAppTemplate	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Acceso libre al backend API y componentes bajo licencia open-source MIT según se especifica en el repositorio público.	Standard	Try
Sectr	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Uso gratuito e ilimitado durante la fase de beta pública.	Standard	Try
Anaconda	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Acceso completo al repositorio público de paquetes de código abierto y herramientas base de gestión.	Single Sign-On Tax (Enterprise SAML)	Try
NestJS SaaS Start	Free	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Repositorio de código abierto totalmente gratuito sin limitaciones de uso.	Standard	Try
BTST	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	El sistema principal es de código abierto y de uso libre.	Standard	Try
Fixrb	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Permanent free tier with monthly usage allowances.	Standard	Try
Unity	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Disponible sin coste para entusiastas y equipos independientes que generen menos de un umbral determinado de ingresos anuales.	Single Sign-On Tax (Enterprise SAML)	Try
DelightQL	Freemium	No credit card requiredCommercial use allowedUnlimited usage with no expiration	Documentation and playground features are accessible free of charge.	Standard	Try

Audited Free & Freemium Platforms (44)

Deno

FreeOpen SourceMIT

Secure JavaScript and TypeScript runtime with built-in tooling and Node.js compatibility.

Native TypeScript support without external build configurations.
Comprehensive built-in tooling including test runners and linters.
Strong compatibility with npm packages and existing Node ecosystems.

108.8kstars on GitHub

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OpenStarterKit

FreeOpen SourceMIT

Open-source Next.js SaaS starter kit featuring Better Auth, Stripe, and Prisma.

Completely free and open source with no licensing fees for initial development
Built on plain Next.js without proprietary compilers or custom framework layers
Includes pre-configured integrations for authentication, database ORM, and billing

22stars on GitHub

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Godot Engine

FreeOpen SourceMIT

Free and open-source 2D and 3D game engine for cross-platform development.

100 percent royalty-free licensing model under the MIT license.
Modular node-based architecture that facilitates component reuse.
Native support for cross-platform development across desktop, mobile, and XR environments.

119.3kstars on GitHub

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Socket.IO

FreeOpen SourceMIT

Bidirectional real-time communication library for Node.js and browsers.

Native automatic reconnection handling network drops.
Compatibility with multiple transports including HTTP long-polling.
Mature ecosystem and adapters for scaling across multiple servers.

63.2kstars on GitHub

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AI SDK

Free

Unified TypeScript SDK for building artificial intelligence applications

Agnostic support for multiple large language model providers
Direct native streaming capabilities for user interfaces
Extensive compatibility with modern JavaScript and TypeScript frameworks

27.6kstars on GitHub

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Flutter

FreeOpen SourceBSD-3-Clause

Open-source framework for building multi-platform applications from a single codebase.

Native compilation to ARM and Intel machine code for optimal performance.
Hot reload capability for rapid development iteration.
Open-source ecosystem with no software licensing fees.

11.3kstars on GitHub

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Temporal

FreemiumOpen SourceMIT

Open source durable execution platform for building resilient applications

Eliminates the need to write complex manual retry logic and distributed state management
Excellent support for self-hosting via its open source core
Complete event history per workflow execution for advanced debugging

24.0kstars on GitHub

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Project Jupyter

Free

Web-based interactive computing platform for data science and executable code.

Native support for over forty programming languages including Python and R
Open modular architecture extensible via plugins and web interfaces
Open JSON-based document format for straightforward version control

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GNU

Freemium

Free operating system developed to guarantee computer user freedom.

Completely free and open source software without proprietary restrictions.
Total control over the operating system and execution tools.
Broad compatibility and adoption across multiple distributions and architectures.

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Bun

Free

A fast all-in-one JavaScript runtime and toolkit.

Extremely fast execution and dependency resolution compared to Node.js
Natively integrated npm-compatible package manager
Test runner and bundler included within the same binary

96.5kstars on GitHub

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Appwrite

FreemiumOpen SourceBSD-3-Clause

Open-source backend platform for developers and agents featuring auth, databases, and storage.

Unified all-in-one backend platform reducing the overhead of integrating multiple third-party services.
Fully open-source architecture with official support for self-hosting through Docker.
Native support for MCP protocols and advanced integration with autonomous coding agents.

57.8kstars on GitHub

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Medusa

Freemium

Open-source digital commerce platform with a modular framework for developers.

Highly customizable modular architecture tailored for developers.
Open-source ecosystem built with TypeScript and Node.js.
Extensive flexibility for integrations via REST and GraphQL APIs.

37.0kstars on GitHub

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Brut

Free

Single-file POSIX shell script router for building Unix command-line programs.

High portability based strictly on POSIX standards
Zero external runtime dependencies
Lightweight single-file script architecture

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Unreal Engine

Freemium

Real-time 3D creation tool for game development, visualization, and immersive experiences.

Top-tier real-time rendering capabilities with Nanite and Lumen technologies.
Accessible business model with no upfront license costs for most independent developers.
Open ecosystem with full access to C++ source code for deep engine customization.

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Keycloak

FreeOpen SourceApache-2.0

Open source identity and access management solution with single sign-on capabilities.

Completely open source with no commercial licensing fees.
Native support for OpenID Connect, OAuth 2.0, and SAML 2.0 standards.
Built-in identity brokering and social login integration.

37.6kstars on GitHub

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Prisma

FreemiumOpen SourceApache-2.0

TypeScript agent infrastructure combining type-safe ORM, managed Postgres, and native app hosting.

End-to-end type safety connecting database schemas directly to application code.
Unified platform combining database hosting, ORM, and compute in a single project.
Streamlined developer experience with powerful CLI tooling and native agent support.

47.7kstars on GitHub

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PocketBase

Free

Open source backend in a single file with realtime database and authentication.

Extremely simple deployment through a single binary executable.
Embedded SQLite database with real-time query support.
Built-in web admin dashboard requiring zero extra configuration.

244stars on GitHub

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Backenly

FreemiumOpen SourceApache-2.0

The autonomous backend built for coding agents over MCP.

Native integration via MCP protocol for coding agents.
Isolated PostgreSQL schema per project with pgvector support.
Automated monitoring and self-repair capabilities every minute.

103stars on GitHub

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Cove

FreeOpen SourceUnlicense

A minimal starter stack for TanStack Start with end-to-end type safety.

Native end-to-end type safety with TanStack Router
Minimal setup without redundant boilerplate code
Direct integration with Drizzle ORM and Better Auth

1.4kstars on GitHub

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Popkern

FreeOpen SourceAGPL-3.0

An open-source parametric BRep CAD kernel written in Rust for solid geometric modeling.

Written in Rust for high performance during complex geometric computations.
Permanently open-source and free for all developers and creators.
Native support for STEP file import and export alongside Rhai scripting.

23stars on GitHub

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B2B SaaS Starter

FreeOpen SourceMIT

Cloudflare-first B2B SaaS infrastructure starter template for rapid application development.

Architecture optimized for Cloudflare Workers and D1
Includes structured logging and request tracing
Open-source MIT model suitable for self-hosting

53stars on GitHub

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栖梧 Qiwu

FreeOpen SourceMIT

Open-source Node full-stack admin template built with NestJS and Vue 3

Unified TypeScript stack across backend, frontend, and mobile apps.
MIT license allowing unrestricted self-hosted deployments.
Integrated scaffolding and code generation tools for rapid feature creation.

93stars on GitHub

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Xano

Freemium

Comprehensive backend platform to build, run, and govern AI-powered software.

Scalable infrastructure based on PostgreSQL and Kubernetes.
Centralized data governance and business rules for teams.
Automated OpenAPI documentation and integrated deployment pipelines.

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KeystoneJS

FreeOpen SourceMIT

Programmable headless content management system based on Node.js and GraphQL.

Automatically generated GraphQL API from data schemas.
Highly flexible headless architecture fully customizable via code.
Intuitive admin interface generated without manual setup.

10.0kstars on GitHub

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Payload

FreemiumOpen SourceMIT

Open-source headless CMS and application framework built with TypeScript and React.

Code-first architecture using TypeScript for data schema definition.
Highly extensible with native support for hooks, custom validation, and dynamic fields.
Flexible deployment within your own infrastructure, reducing third-party dependency.

45.7kstars on GitHub

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Hasura

Freemium

GraphQL engine and data delivery network for secure APIs and artificial intelligence applications.

Instant generation of GraphQL APIs from existing relational database schemas
Role-based access control integrated directly into the data layer
Support for complex queries, filtering, and pagination without writing repetitive backend code

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Strapi

Freemium

Open-source Node.js and TypeScript headless CMS for flexible API-driven applications.

Fully extensible architecture built with Node.js and TypeScript.
Instant REST and GraphQL API generation from content schemas.
MIT license ensures complete ownership of source code and data.

73.4kstars on GitHub

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PartyKit

FreeOpen SourceMIT

Deployment platform for real-time multiplayer apps, AI agents, and local-first architectures.

Native support for WebSockets and open web standards.
Direct compatibility with popular CRDT and state libraries like Y.js.
Rapid local development and edge deployment workflows.

5.7kstars on GitHub

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Perch

FreeOpen SourceMIT-0

A single-binary IMAP and SMTP server with a POSIX CLI.

Extremely lightweight deployment via a single self-contained binary.
Operates behind NAT or CGNAT without requiring a public IP address.
Supports standard IMAP and authenticated SMTP protocols out of the box.

2stars on GitHub

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Seed

FreeOpen SourceMIT

Open-source MIT-licensed SaaS starter built on web standards and Deno.

MIT license with no commercial restrictions or paywalls
Runs natively on Deno with streamlined Docker Compose deployment
Includes 2FA authentication, role management, and Stripe billing out of the box

34stars on GitHub

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Maple

Free

Sub-2-BPW MoE model compression to run large language models on 6GB VRAM GPUs

100% in-VRAM execution on consumer hardware with limited VRAM.
Eliminates PCIe bus bandwidth transfer bottlenecks.
Open weights format compatible with llama.cpp.

29stars on GitHub

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PyPI

Free

The official software repository for the Python programming language.

Universal access to thousands of verified open-source Python libraries
Native integration with standard package managers like pip
Free and widely adopted public infrastructure across the industry

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Oqtane

FreeOpen SourceMIT

Open source modular CMS and application framework for Blazor and .NET MAUI.

Modular architecture built entirely on C# and Blazor
Fully open MIT license for commercial use
Cross-platform support for web and native apps with .NET MAUI

2.3kstars on GitHub

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instancez

FreemiumOpen SourceApache-2.0

Developer and LLM-friendly Supabase drop-in replacement packaged as a single Go binary.

Drop-in wire compatibility with the standard supabase-js client.
Simplified self-hosting deployment using a single Go binary.
Engineered natively for coding agents and AI assistant workflows.

61stars on GitHub

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ABP Platform

FreemiumOpen SourceLGPL-3.0

Open-source web application framework on top of ASP.NET Core for enterprise apps.

Modular architecture structured following ASP.NET Core best practices.
Pre-built modules that eliminate boilerplate code for standard features.
Multiple UI options including Angular, Blazor, and MVC.

14.5kstars on GitHub

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Deepnote

Freemium

Collaborative data science and analytics workspace with Python and SQL support.

Real-time multi-user collaboration similar to Google Docs for notebooks.
Native integration with multiple SQL data sources and relational databases.
Generation of interactive applications and dashboards directly from code.

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NativeAppTemplate

FreemiumOpen SourceMIT

The fastest way to build a Rails-backed native iOS/Android SaaS app.

True native architecture using Swift and Kotlin.
Structured and scalable backend powered by Ruby on Rails.
Pre-wired authentication and multitenancy components.

15stars on GitHub

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Sectr

FreemiumOpen SourceMIT

Single source of truth and state management for artificial intelligence agents

Direct integration with existing agent frameworks without restructuring
Ability to scale agents to zero during human approval waits
Native support for multiple AI SDKs in Python

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Anaconda

Freemium

Data science and AI platform for Python and R package management and virtual environments.

Vast ecosystem of pre-compiled packages for data science and machine learning.
Efficient management of complex virtual environments and binary dependencies in Python.
Native integration with AI tools and multiple models from the development environment.

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NestJS SaaS Start

Free

SaaS boilerplate built with NestJS and automated TypeDoc generation.

Automated OpenAPI and TypeDoc generation through CI pipelines.
Modular architecture designed for multi-tenant backend systems.
Open source codebase available for self-hosted deployment.

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BTST

FreemiumOpen SourceMIT

Open-source TypeScript system to add full features to your existing React applications.

Fully open-source TypeScript architecture.
Allows adding full-stack plugins without a hosted control plane.
Generated code and UI can be fully ejected and modified.

79stars on GitHub

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Fixrb

FreemiumOpen SourceMIT

A Ruby testing framework where test suites are RFC 2119 specifications without class coupling.

RFC 2119 specification approach for clearer test readability.
Strict class decoupling using duck typing paradigms.
Execution of each context within its own isolated process.

47stars on GitHub

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Unity

Freemium

The leading real-time development engine for building interactive 2D, 3D, and XR experiences.

Cross-platform ecosystem with native deployment to consoles, mobile devices, and XR systems
Extensive developer community with a vast library of ready-to-use plugins and assets
Extensible C#-based visual environment with optimized compilation support

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DelightQL

FreemiumOpen SourceApache-2.0

An advanced query language that transpiles to SQL using functional and logic programming.

Functional and logic programming syntax that simplifies complex queries.
Direct transpilation to standard SQL compatible with multiple engines.
WASM-based interactive execution built right into the documentation.

2stars on GitHub

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