Open-source Retool alternatives

Appsmith is an open-source low-code platform for building custom internal applications such as dashboards, admin panels, customer 360 views, IT automation and service management tools. It aims to simplify building, deploying and maintaining these apps, which otherwise tend to be tedious to code from scratch.

You assemble interfaces visually and connect them to data through integrations with more than 25 databases and any REST or GraphQL API, with JavaScript available where you need custom logic. Topics also point to CRUD generation, workflows and automation. The front end is built with React and TypeScript, and the server side is mostly Java.

You can sign up for Appsmith Cloud or install it on your own machine, with Docker as the recommended method, plus Kubernetes and an AWS AMI. The code is Apache-2.0 licensed. It is a common choice for engineering teams that want to ship internal tools quickly without maintaining a bespoke front-end codebase.

ToolJet is an open-source platform for creating internal software, including admin panels, dashboards and operational apps that sit on top of your existing databases, APIs and SaaS systems. Apps are assembled visually in a builder, so teams can ship tools without writing a full front end.

AI plays a large role. ToolJet AI turns a text description into pages, queries and components, and a Model Context Protocol server lets coding agents such as Claude Code and Codex build and modify ToolJet apps directly. Agents work against the platform's real component and data contracts, so the output is an ordinary ToolJet app that the team can keep editing in the visual builder with the same permissions, environments and version history. Workflows and AI agents are part of the offering.

You can self-host ToolJet or use ToolJet Cloud, and the open-source foundation is AGPL-3.0 licensed with a JavaScript and TypeScript codebase. It targets teams that need internal software quickly and want an open-source option with a managed alternative.

Refine is a React-based framework aimed at internal tools, admin panels, dashboards and business-to-business applications. It is described as headless, meaning it provides the logic for data fetching, routing, authentication and other CRUD concerns through hooks and components while leaving the visual layer to the UI library you prefer.

Its topics reference Ant Design, GraphQL, NestJS and Next.js, which reflects the range of UI kits, data sources and runtimes it can be paired with. Because it builds on plain React, teams can use it as a low-code accelerator for common admin screens while still writing normal TypeScript where they need custom behavior.

Refine is MIT licensed and distributed as npm packages, with the core published as @refinedev/core. It runs inside your own project, so there is nothing to host separately. It suits front-end teams who are tired of hand-building the same tables, forms and permissions in every back-office project.

Budibase is an open-source operations platform for building AI agents, automations and apps that run internal processes. It is model agnostic and describes itself as saving engineers many hours when building these tools, while handling security concerns. Topics place it in the low-code and no-code internal tools space, with CRUD apps and an SQL GUI.

The idea is to run requests, approvals and workflows on one platform instead of stitching several tools together. Staff constantly ask questions, request sign-offs and flag problems, and Budibase agents interpret those requests and carry out the work: creating records, sending approvals to the right people, updating apps and alerting teams. You connect the business systems your operations already rely on, and the platform also supports building data applications over databases and REST APIs.

You can use Budibase Cloud, where the vendor hosts it, or host it yourself with Docker, Kubernetes or DigitalOcean. The repository is written in TypeScript, and its license is listed as 'Other' on GitHub, so check the terms for enterprise features. It suits operations and engineering teams that want internal tools and AI automation without building everything from scratch.

NocoBase is an open-source platform that combines AI with no-code tooling to build business systems quickly. Rather than having AI generate everything from scratch, it has AI build on infrastructure already proven in production and on a visual WYSIWYG no-code editor, which the project says delivers both speed and reliability.

Its approach is collaborative: coding agents are given a complete CLI plus skills, and people use a visual interface, so both can contribute to the same system. Topics show typical uses such as internal tools, admin dashboards, CRUD apps, CRM, ERP and project management, with workflows included. An online demo, documentation, a forum and customer stories are available, and release notes are published on the blog with weekly summaries. It is written in TypeScript.

NocoBase can be installed on your own infrastructure, and its license is listed as 'Other' on GitHub, so review the terms for commercial or enterprise use. It suits teams that want flexible internal systems without maintaining a large custom codebase, and who want to use AI assistance on a stable foundation.

Windmill is an open-source platform for developers to run internal code as APIs, background jobs, workflows and user interfaces. It is pitched as a self-hostable alternative to Retool, Pipedream and Superblocks and as a simplified version of Temporal, and it automatically generates UIs so a script can be shared and triggered as an internal app.

Scripts can be written in languages including Python, TypeScript, Go, Bash, SQL, PowerShell, Rust and GraphQL. They can be composed into flows or used within richer apps built with its low-code builder. The backend is written in Rust on PostgreSQL, and the README describes it as a very fast self-hosted workflow engine, citing a comparison with Airflow. Sections of its documentation cover main concepts, local development, architecture, security, performance and self-hosting with Docker Compose.

Windmill is open source under AGPLv3, and Windmill Labs sells dedicated instances, commercial support and licenses, so the repository license is listed as 'Other' on GitHub. It suits engineering teams that want to turn existing scripts into reliable internal tools and automations without building each interface by hand.

Lowdefy is an open-source framework for building web apps from configuration files rather than code. Its pitch is that concise, schema-validated config is easier for both people and AI tools to generate, review, and maintain than thousands of lines of generated React. It is released under the Apache-2.0 license.

Apps are described in YAML, and the runtime interprets the config instead of executing arbitrary code, with authentication, permissions, and data validation built in. The framework includes over 70 UI components such as forms, tables, charts, and markdown, more than 50 logic operators for dynamic behavior, and over 10 data connectors including MongoDB, PostgreSQL, MySQL, REST APIs, Google Sheets, and S3.

It is built on Hono, Vite, and Auth.js and can be deployed anywhere Node.js runs. A framework update upgrades every app at once, which the authors present as a maintenance benefit. It suits teams building CRUD apps, admin panels, dashboards, and workflow tools who want something between a low-code platform and a custom codebase.

Erupt is a Java admin framework built on a code-as-configuration idea: annotate an entity class with @Erupt and a complete admin page is generated at runtime, with no controllers, front-end build, or scaffolding. It targets Java 17 and Spring Boot 3.x, starts in a few seconds, and is released under the Apache-2.0 license.

The framework ships more than 30 UI components, including date pickers, sliders, trees, code editors, reference tables, autocomplete, maps, signatures, and Markdown. Role-based access control, audit logs, Excel import and export, and OpenAPI support are built in, and every annotated entity becomes a permission-aware REST endpoint.

Newer releases add AI features: connections to more than 50 LLM providers, MCP-native tools, and skills for coding agents, positioned as an AI harness for admin apps. Documentation is available in English and Chinese, with a live demo. Erupt suits Java teams that want to ship internal tools and back-office systems quickly without maintaining a separate front end.

Avo is a customizable admin panel framework, content management system, and internal tool builder for Ruby on Rails. It aims to save engineering teams months of development time. It is powered by Hotwire and configured entirely by writing Ruby code. The input lists its license only as other, so check the repository and website for editions and terms.

Its resource management can create a CRUD interface for Active Record models with a single command, removing the need to copy and paste views and controllers. Topics mention dashboards, CRM and CMS use, and a UI builder. The project provides installation docs, a demo app, a roadmap, an issue tracker, and GitHub Discussions.

Avo suits Rails teams that need back-office tools, admin dashboards, or internal CRMs without building each screen by hand, and that prefer to keep the admin code in the same repository and language as the application.

Motor Admin is a Rails engine that provides a low-code admin panel and business intelligence tools for a Rails application. Everything can be configured from a settings interface with no DSL, and it is presented as a modern alternative to Rails Admin, Active Admin and Blazer. It is aimed at Rails teams who want internal tools and dashboards quickly without hand-coding screens.

Features include customizable CRUD, custom actions through Active Record method calls or API endpoints, virtual attributes, a forms builder, SQL queries with embedded variables, data visualization and dashboards, email alerts, authorization, Active Storage support, search, internationalization, a mobile-friendly layout, configuration sync between environments, authentication, multiple databases, audit logs, collaboration notes and personalized report alerts via Slack. Resource pages can show data from SQL queries and attached dashboards.

The engine is installed by adding a gem and running a migration. The core is MIT licensed, and a Pro edition adds white-label styling and logos, multi-factor authentication and SSO or SAML. A demo app is available for trying it out.