Appsmith

Appsmith is an open source, low-code application builder designed for developers who need to create internal tools, admin panels, and CRUD (create, read, update, delete) applications quickly. By combining a visual drag-and-drop interface with full JavaScript customization support and native database and API connectivity, Appsmith empowers development teams to ship internal tooling without the overhead of building custom web interfaces from scratch.

The canvas-based editor in Appsmith is the primary workspace for application development. Developers drag widgets from the component library onto a canvas and arrange them to create the desired layout. The widget library includes tables, forms, charts, buttons, inputs, dropdown selects, date pickers, modals, tabs, file uploaders, maps, rich text editors, and many more. Each widget's properties are configurable through a properties panel and support dynamic values using JavaScript expressions and bindings to query data.

Data sources in Appsmith include all major relational databases (PostgreSQL, MySQL, SQL Server, Oracle), NoSQL databases (MongoDB, Redis), cloud data warehouses (BigQuery, Snowflake, Redshift), GraphQL and REST APIs, SAAS tools (Twilio, SendGrid, HubSpot, Salesforce, Google Sheets, S3), and document databases. Data source connections are configured once and made available across all applications in the workspace, with credentials managed securely.

Queries connect widgets to data by fetching or modifying data from the configured data sources. SQL queries, MongoDB aggregations, and API call configurations are written in a query editor. Query results are automatically available as bindable data in widget properties using double curly brace syntax. Queries can be triggered automatically when the page loads, or on demand when users interact with widgets.

JavaScript logic in Appsmith can be written in query transformers, widget event handlers, and JSObjects. JSObjects are reusable JavaScript modules within an application that can define functions, constants, and stateful variables accessible from any widget or query on the page. This code capability allows implementing complex business logic, data transformations, and custom behaviors that go beyond what declarative bindings can express.

The access control system in Appsmith supports workspace members, application viewers, and application editors with configurable permissions. Enterprise features add custom roles, SAML SSO, audit logs, and environment-specific configurations.

Appsmith is self-hostable using Docker or Kubernetes, and a managed cloud version is available for teams that prefer not to manage infrastructure. As an open source project with a large community, Appsmith benefits from continuous feature development and a growing library of community templates.