10 Best Open Source Low-Code Platforms for Building Apps in 2026

The best open source low-code app builder should give you more than a public repository.

It should let you self-host, understand the license, control your data, and build real applications without discovering that essential features are locked behind a paid tier.

This guide compares 10 low-code open source platforms based on their licenses, self-hosting requirements, free-version limits, community health, and production capabilities.

It also separates fully open-source options from open-core products, so you can see what remains free before committing your app to the platform.

Why Builders Go Open Source for Low-Code

Low-code web application development with open source tools appeals to builders who want the speed of low-code without surrendering control of their apps, data, or infrastructure.

The main reasons are:

• Self-hosting and data control: Teams can choose where the platform runs and keep sensitive data on infrastructure they manage.
• Fewer per-user costs: A self-hosted low-code platform may avoid fees that increase whenever another employee, client, or customer needs access.
• Freedom to extend: Developers can inspect the source, add integrations, modify components, and work around limitations instead of waiting for the vendor.
• Protection from vendor changes: Access to the software reduces the risk that a shutdown, price increase, or product change makes an existing app unusable.

Control is a recurring theme in community discussions about open-source low-code platforms.

One builder explained their preference plainly: “I want it to be self-hosted because I want to have control.” Another warned that many platforms “look free at first but later limit users, workflows, or branding.”

Open source does not make hosting, upgrades, security, or maintenance effortless.

It gives the organization the option to manage those responsibilities itself instead of being permanently tied to one vendor’s pricing and roadmap.

How We Judged These Platforms

The best open source low-code platform is not simply the one with a public GitHub repository.

We evaluated each option based on what its license allows, what the free self-hosted version includes, and whether it can support a real production app.

The main criteria were:

• License type: We checked whether the platform uses a permissive license such as MIT or Apache 2.0, a copyleft license such as AGPL, or an open-core model with proprietary extensions.
• Commercial use: We looked at whether businesses can modify, host, and use the software commercially without paying for a separate licence.
• Free-version limits: We identified whether essential features such as roles, permissions, SSO, white-labeling, workflows, or user capacity sit behind a paid tier.
• Self-hosting effort: We considered installation requirements, supported deployment methods, upgrades, backups, and the technical skill needed to keep the platform running.
• Community health: We reviewed documentation, repository activity, user discussions, and the size of the contributor ecosystem.
• Production readiness: We assessed whether the platform can handle authentication, data, application logic, deployment, monitoring, and ongoing maintenance.

The distinction between open source and open core matters.

A fully open platform makes the complete product available under an open-source licence, while an open-core platform keeps the foundation public but reserves some advanced or essential features for paid editions.

Neither model is automatically better.

The important question is whether the free version includes everything your app requires, especially user roles, access controls, and deployment features that are difficult to replace after the build begins.

The 10 Best Open Source Low-Code Platforms

The best open source low-code platforms range from visual internal-tool builders to code-first frameworks that generate applications you can fully own.

The table below summarizes their licences, free self-hosted editions, and strongest use cases before the detailed reviews.

1. Appsmith

Best for: Internal tools, dashboards, and admin panels connected to existing databases and application programming interfaces (APIs).

Appsmith is an open source low-code app builder with a drag-and-drop interface, JavaScript customization, and integrations for databases, software-as-a-service (SaaS) tools, and APIs.

Licence and what is free: The Community Edition uses the permissive Apache 2.0 licence and can be self-hosted for free. The open edition includes the visual builder, integrations, Git version control, public apps, Google SSO, and three standard roles.

Custom roles, workflows, audit logs, premium integrations, and removal of Appsmith branding sit in the paid Business edition.

Key capabilities

• Drag-and-drop tables, forms, charts, and other widgets
• Connections to more than 25 database types and external APIs
• JavaScript for custom queries, transformations, and interface behavior
• Git-based version control and reusable application components
• Authentication and standard role-based access

Self-hosting and setup: Appsmith supports container-based self-hosting and is suited to teams already comfortable operating Docker or Kubernetes infrastructure.

Users value its mature ecosystem, extensive integrations, and ability to place a working interface over existing data quickly. Its GitHub repository had nearly 40,000 stars and more than 300 releases as of 2026, making it one of the most established projects on this list.

Limitations

• Best suited to internal tools rather than highly differentiated customer products
• Advanced access controls and workflows require a paid edition
• Complex interfaces rely increasingly on custom JavaScript
• Application definitions remain tied to the Appsmith runtime

Pricing: Community is free and open source; Business starts at $15 per user per month, while Enterprise starts at $2,500 per month for 100 users. The Appsmith pricing details were verified in July 2026.

Why it earns its spot: Appsmith combines a mature community, broad integrations, and a practical visual builder for teams that need internal applications quickly.

2. ToolJet

Best for: Teams creating internal dashboards, forms, workflows, and operational applications.

ToolJet is an AGPLv3-licensed visual app builder with a built-in database, more than 45 interface components, multiplayer editing, and connections to common databases, APIs, and business services.

Licence and what is free: The self-hosted Basic edition is free but limited to two builders, 50 end users, two applications, two workflows, and one workspace.

It includes predefined roles and community support, while custom groups, SSO, audit logs, Git synchronization, white-labeling, and unlimited apps require paid plans.

Key capabilities

• Responsive drag-and-drop interface builder
• Built-in ToolJet Database
• Database, Representational State Transfer (REST) API, SaaS, and object-storage connections
• Multipage apps and collaborative editing
• Workflows using visual nodes, JavaScript, or Python

Self-hosting and setup: ToolJet can run through Docker Compose, cloud virtual machines, Kubernetes, or on-premise infrastructure. Community users describe Docker-based setup as relatively straightforward, although production deployments still require server, database, backup, and security management.

Limitations

• The free edition now has firm app, builder, and user limits
• Many governance and deployment features require the Team edition
• Primarily optimized for internal apps rather than custom public products
• AGPL obligations or a commercial agreement may matter when embedding it in another product

Pricing: The self-hosted Basic edition is free, while the paid self-hosted Team plan costs $199 per builder per month, billed annually. The ToolJet pricing details were verified in July 2026.

Why it earns its spot: ToolJet provides a polished internal-app builder and built-in database, but buyers should examine the free edition’s current limits before committing.

3. Modelence

Best for: Builders who want AI speed while keeping a conventional, production-ready codebase.

Modelence is an open source low-code app builder built around AI generation rather than a visual drag-and-drop editor.

A prompt produces the frontend, backend, database structure, authentication, and application logic as readable TypeScript, React, Node.js, and MongoDB code.

Licence and what is free: The underlying Modelence framework uses Apache 2.0, allowing commercial use, modification, and redistribution. The free App Builder plan includes AI usage for prototyping, a managed database, storage, and a Modelence subdomain.

Every generated application provides access to the full source code.

Key capabilities

• AI-generated frontend and backend code
• Built-in MongoDB data stores, schemas, indexes, and migrations
• Authentication, sessions, roles, and password-reset workflows
• Scheduled jobs for recurring and background tasks
• Logs, metrics, tracing, deployment, and autoscaling through Modelence Cloud
• Exportable code that can run on another Node.js hosting platform

Self-hosting and setup: Developers can create a local project with the Modelence command-line interface, connect their own MongoDB database, and deploy the compiled application to standard Node.js infrastructure. Managed deployment is available for teams that do not want to operate the stack themselves.

What users like: The clearest advantage is that the generated output is a conventional full-stack project rather than an application definition that requires a proprietary visual runtime.

Limitations

• It is not a traditional drag-and-drop low-code editor
• Builders still need to understand users, data relationships, and application requirements
• The community and integration ecosystem are younger than those of Appsmith, Frappe, or Refine
• It currently focuses on web applications rather than native mobile apps

Pricing: The framework is open source and the App Builder is free to try; managed production plans start at $20 per month, with compute billed according to the selected resources.

Why it earns its spot: Modelence is the strongest fit for builders who want to move quickly with AI without accepting a closed visual runtime or surrendering their code.

4. Budibase

Best for: Fast CRUD applications, forms, approval processes, and operational workflows.

Budibase combines a visual application builder, an internal database, external data connections, automations, and AI agents. It is designed primarily for internal tools and workflow applications.

Licence and what is free: The main platform uses GPLv3, while its client and component libraries use MPL, allowing applications built with them to carry a licence chosen by the builder. The free self-hosted edition includes unlimited users, apps, automations, agents, and actions, but only one workspace.

Paid self-hosted features include custom branding, backup and restore controls, environment variables, user groups, enforced SSO, audit logs, and directory synchronization.

Key capabilities

• Drag-and-drop responsive app builder
• Built-in database and external data sources
• Automation triggers, actions, and webhooks
• Custom interface and data-source plugins
• Role-based access and SSO in the open edition

Self-hosting and setup: Budibase provides a command-line tool for Docker Compose deployments and also documents Kubernetes, DigitalOcean, and Windows Server installations. Its documentation warns that self-hosters remain responsible for server security, persistence, updates, and troubleshooting.

Users often praise how quickly it creates basic CRUD tools. Community feedback becomes more mixed when applications require complex programming logic or less opinionated workflows.

Limitations

• The open edition is limited to one workspace
• Advanced governance, backups, and white-labeling require Enterprise
• The platform becomes restrictive for highly custom logic or interfaces
• Self-hosted installations require outbound connectivity for licence activation and validation

Pricing: The open-source self-hosted edition is free; the paid cloud Pro plan starts at $19 per month when billed annually, while self-hosted Enterprise uses custom pricing. The Budibase pricing details were verified in July 2026.

Why it earns its spot: Budibase offers one of the fastest routes from a database to a useful operational application, particularly when the workflow fits its conventions.

5. NocoBase

Best for: Business systems with complex data relationships and a need for plugin-based extension.

NocoBase is a data-model-driven platform that separates the underlying data structure from the pages and interface blocks that display it.

Users can configure systems through a what-you-see-is-what-you-get (WYSIWYG) interface or extend the platform through plugins and code.

Licence and what is free: NocoBase changed its core licence from AGPLv3 to Apache 2.0 in February 2026. The Community Edition includes full source access, self-hosting, unlimited users, unlimited apps, unlimited records, authentication, roles, permissions, and basic workflows.

The commercial structure still matters. Community retains NocoBase branding and is positioned for internal systems, while developing configurable systems for clients is listed as a Professional feature. Standard costs $800 as a lifetime licence, and Professional costs $8,000.

Key capabilities

• Visual data modeling and WYSIWYG page configuration
• Authentication, permissions, workflows, and notifications
• Plugin-first architecture
• PostgreSQL, MySQL, and MariaDB support
• AI-assisted building and AI employees
• Extensible React and Node.js foundation

Self-hosting and setup: Docker Compose is the recommended deployment method. Production use also requires a reverse proxy, persistent storage, backups, and careful version management.

Users value the data-first approach, flexible plugin architecture, and lack of user or record limits in Community.

Limitations

• Advanced workflows, SSO, version control, external data sources, and development environments sit in commercial editions
• Client-development rights should be reviewed carefully before agency use
• The plugin model introduces more concepts than a simple visual builder
• Upgrading to a higher edition is supported, but downgrading is not

Pricing: Community is free; Standard is a one-time $800 purchase, Professional is $8,000, and Enterprise is custom. The NocoBase pricing details were verified in July 2026.

Why it earns its spot: NocoBase is a strong choice when the database model is the center of the application and visual pages must remain configurable over time.

6. Frappe

Best for: Complex business systems, enterprise workflows, and ERP-style applications.

Frappe is a full-stack, metadata-driven low-code web framework written in Python and JavaScript. Its DocType model can define a database table, form, controller, permissions, and API within one structure.

Licence and what is free: The Frappe Framework is fully available under the MIT licence with no software licence fee, user cap, or paid feature gate in the core framework. Frappe charges for optional hosting, support, consulting, and other services rather than access to the software.

Key capabilities

• Visual forms, lists, reports, dashboards, calendars, and Kanban views
• Fine-grained user, role, and record permissions
• Automatically generated REST APIs
• Workflows, notifications, background jobs, email, and print formats
• Multi-site and multi-tenant deployment
• Python and JavaScript extension points

Self-hosting and setup: Frappe supports Docker and its Bench command-line tool. The framework includes many production features, but operating its MariaDB, Redis, workers, queues, web server, and updates requires meaningful technical knowledge.

The project has a mature forum, thousands of GitHub contributors and users, and a large ecosystem built around ERPNext and other Frappe applications.

Users in the supplied self-hosted discussion praised the framework’s depth but also noted its setup and learning curve.

Limitations

• More framework than beginner-friendly visual builder
• Advanced customization requires Python and JavaScript
• The default stack is opinionated around MariaDB, Redis, and Frappe conventions
• Customer-facing interface work may require more custom development

Pricing: Self-hosted software is free; managed Frappe Cloud site hosting starts at $5 per month. The Frappe pricing details were verified in July 2026.

Why it earns its spot: Frappe is one of the most complete fully open-source options for serious business applications, provided the team can learn and operate its stack.

7. Windmill

Best for: Developer-led workflows, scripts, data pipelines, operational tools, and background jobs.

Windmill turns scripts written in TypeScript, Python, Go, Bash, Structured Query Language (SQL), and other languages into workflows, APIs, scheduled jobs, and user interfaces.

It is more code-oriented than most visual builders on this list.

Licence and what is free: Windmill Community Edition uses AGPLv3. It is free for internal organizational use and includes unlimited executions, up to 50 users, three workspaces, four permission groups, and SSO for up to 10 users. Embedding or reselling Windmill functionality may require AGPL compliance or a commercial licence.

Key capabilities

• Scripts exposed as jobs, webhooks, APIs, and scheduled tasks
• Visual flow editor and application builder
• Git deployments and infrastructure-as-code support
• PostgreSQL, WebSocket, MQTT, and email triggers
• Docker, Kubernetes, and Amazon Web Services Fargate deployment
• Multiple language runtimes

Self-hosting and setup: Windmill can be deployed quickly with Docker or Kubernetes, but production use requires worker configuration, database management, secrets, queues, and scaling decisions.

Users value its ability to keep real code at the center of workflows. One participant in the self-hosted discussion said they had encountered few meaningful limits in Community, while also noting that it is less no-code than many alternatives.

Limitations

• Enterprise observability, audit logs, autoscaling, advanced triggers, and deployment environments are paid
• Community is limited to three workspaces and four groups
• It assumes more programming knowledge than a typical visual builder
• Commercial embedding has additional licence considerations

Pricing: Community is free; paid self-hosted Enterprise pricing starts at $120 per month before developer seats and compute resources are added. The Windmill pricing details were verified in July 2026.

Why it earns its spot: Windmill is a strong option when the application is primarily a collection of workflows, scripts, and operational interfaces rather than a highly customized consumer product.

8. Refine

Best for: React developers building admin panels, dashboards, internal tools, and B2B applications.

Refine Core is a headless React framework that handles repetitive CRUD, authentication, routing, data-provider, state-management, and access-control patterns without forcing a particular interface library.

Licence and what is free: Refine Core uses the MIT licence and is free to use, modify, self-host, and deploy commercially. There are no runtime user fees or feature tiers in the open framework. Refine also sells separate AI generation and Enterprise products.

Key capabilities

• React and TypeScript project generation
• Support for Ant Design, Material UI, Tailwind, Mantine, Chakra UI, and custom components
• Authentication, access control, routing, forms, and data providers
• Connections to REST, GraphQL, Supabase, Firebase, and other backends
• Standard source code that can deploy to any React-compatible host

Self-hosting and setup: Refine does not include a complete hosted runtime or database. Developers choose and operate their own frontend host, backend, authentication service, database, and monitoring stack.

React developers value its flexibility, active community, and ability to accelerate CRUD-heavy work without replacing the underlying codebase. The repository had more than 34,000 GitHub stars as of 2026.

Limitations

• Requires React and TypeScript knowledge
• Not a true no-code tool
• Database, backend, deployment, and monitoring remain separate decisions
• Some enterprise packages and AI-builder features are commercial

Pricing: Refine Core is free; the optional Refine AI Pro plan costs $20 per month and includes code export. The Refine pricing details were verified in July 2026.

Why it earns its spot: Refine gives React teams low-code speed while leaving them with ordinary application code and no proprietary runtime dependency.

9. Lowcoder

Best for: Feature-rich internal tools and client-facing applications that need more visual flexibility.

Lowcoder is an open source Retool alternative with a WYSIWYG editor, a large component library, database and API connections, JavaScript customization, workflows, and embeddable applications.

Licence and what is free: The Community Edition uses AGPLv3 and is free to self-host without per-user charges. The project also provides an Enterprise Edition with additional development-environment, governance, and support capabilities.

Key capabilities

• Rich selection of tables, charts, forms, layouts, and media components
• Connections to databases, REST APIs, and streaming sources
• JavaScript queries and custom components
• Workspaces, users, groups, themes, and application embedding
• Internal and customer-facing app support

Self-hosting and setup: Lowcoder provides an all-in-one Docker image for small installations, separate stateless services for scaling, and Helm charts for Kubernetes.

The basic image can run with one central processing unit (CPU) core and 2 GB of memory.

The Reddit thread supplied for this article includes particularly positive feedback about Lowcoder’s number of widgets, frontend presentation, self-hosting, and affordable access to maintainer support.

Limitations

• Smaller community and lower visibility than Appsmith or ToolJet
• Documentation and terminology can feel less polished
• MongoDB, Redis, and several services must be managed for scaled deployments
• Enterprise-grade environment separation and governance require paid capabilities

Pricing: Community self-hosting is free. Enterprise licensing starts at $169 per instance per month or uses an alternative API-call model; managed private instances start at $149 per month. The Lowcoder pricing details were verified in July 2026.

Why it earns its spot: Lowcoder offers an unusually broad component set and more polished client-facing presentation than many internal-tool-first alternatives.

10. Saltcorn

Best for: Small database applications, customer relationship management (CRM) systems, directories, and administrative tools with minimal software cost.

Saltcorn is a fully open source no-code database application builder. Users define tables and relationships, then create views, pages, actions, and workflows around that data.

Licence and what is free: Saltcorn uses the permissive MIT licence, and the complete core platform is free to self-host. Its repository includes the code needed for both individual and multitenant installations, without a separate paid feature edition.

Key capabilities

• Database tables, fields, relationships, and calculated values
• Forms, lists, filters, layouts, actions, and role-based views
• Plugin-based extension
• Web and mobile database applications
• PostgreSQL for production and SQLite for local testing

Self-hosting and setup: Saltcorn offers Node.js, Docker, and one-click cloud-server installation options. Its documentation recommends a 2 GB virtual private server for most small installations.

Users in the supplied threads described it as fully open source and effective for CRM and human-resources applications. Its smaller community also means fewer tutorials, integrations, templates, and commercial support options.

Limitations

• Smaller ecosystem and contributor base
• Interface design is more functional than highly polished
• Less suitable for unusual frontend experiences or heavy custom logic
• Administrators must handle security, backups, updates, and infrastructure
• Its security guidance warns that untrusted tenant administrators can create serious server risks

Pricing: The software is free; costs come from the server, database, backups, and any outside support you choose. The Saltcorn pricing details were verified in July 2026.

Why it earns its spot: Saltcorn is one of the clearest options for builders who want a genuinely free, permissively licensed database app builder without an open-core feature wall.

Which Platform Should You Pick?

The best open source low-code platform depends on what you are building, how much code you are comfortable writing, and which limits you can accept in the free version.

Check the licence and paid-feature boundaries before choosing.

A platform may be free to self-host but still reserve custom roles, SSO, white-labeling, workflows, or deployment controls for a commercial edition.

When Low-Code Stops Being Enough

Open source low-code web app builders work best when the application follows familiar patterns such as forms, dashboards, approvals, database records, and internal workflows.

They become less effective when the project requires:

• A highly differentiated customer-facing interface
• Complex or unusual business logic
• Fine-grained performance optimization
• Heavy real-time processing
• Deep integration with legacy or undocumented systems
• Infrastructure that must scale in a very specific way
• Features the platform’s runtime or plugin model does not support

The ceiling depends on the type of platform.

• Database-first platforms are strong for structured business systems but can feel restrictive when the interface becomes highly custom.
• Visual app builders speed up internal tools but may require increasing amounts of JavaScript or paid extensions as the workflows become more complex.
• Code-first frameworks provide more freedom, but they also require developers to choose and maintain the backend, hosting, and infrastructure.
• AI generation on an open framework reduces repetitive development while leaving the complete codebase available for direct changes.

Low-code stops being enough when working around the platform takes more time than writing the required feature directly.

At that point, the ability to access and modify the underlying code becomes more important than the visual builder itself.

Build on an Open Source Foundation With Modelence

An open source low-code app builder should help you move faster without locking the finished product into a proprietary runtime.

Modelence generates a full-stack web app on its Apache 2.0-licensed framework, giving you access to every line of the resulting code.

Describe the app you want, and Modelence builds the frontend, backend, and data model with production features already connected:

• A built-in database with schemas, indexes, migrations, and backups
• Authentication, sessions, user roles, and access controls
• Scheduled jobs for recurring and background workflows
• Logs, traces, and performance monitoring
• Managed deployment with autoscaling, Secure Sockets Layer (SSL), and custom domains

The generated TypeScript, React, Node.js, and MongoDB applications can be inspected, modified, exported to GitHub, or hosted elsewhere. This gives builders AI-assisted speed while preserving the control expected from an open-source foundation.

Modelence app builder is free to try for builders who want to create production apps without assembling the full stack themselves.