BESSER vs UMLet
BESSER
besser-pearl.orgUMLet
umlet.comSide by side
| Figure | BESSER | UMLet |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | Yes | — |
| Web | Yes | Yes |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| API | Yes | — |
| Self-hosted | Yes | — |
| Plans published | 2 | 2 |
| Spec score · UML Modeling Software | 9.0 (#1) | 7.9 (#12) |
| Free plan | Yes | Yes |
| Integrations | Documented generation targets include Python, FastAPI, Django, SQLAlchemy, SQL, Java, React, PyTorch and TensorFlow. | UMLet is available as a stand-alone app, Eclipse plugin, browser app called UMLetino, and Visual Studio Code extension. |
| License | BESSER is open source under the MIT license. | The UMLet site identifies the software as open source under GNU GPL 3.0. |
| Support | The project offers an on-page assistant without an account, email support, and GitHub bug triage weekly. | The project asks users to email [email protected] or create a GitHub ticket for bugs and feedback. |
| System requirements | Current documentation tests Python 3.11 and 3.12; local editor development additionally needs Git, Docker and Node.js 20 or newer. | The FAQ says the stand-alone application runs on Java platforms such as Windows, Linux, and macOS, and requires Java to be installed. |
Plans
In their own words
BESSER
BESSER is an open-source low-code platform for building smart applications by modeling once and generating APIs, databases, agents, and deployments. Its 15+ generators cover databases, REST APIs, web apps, AI agents, and deployment manifests. Built-in modeling includes class diagrams, state machines, object diagrams, agents, and deployment specifications. The GUI Creator deterministically generates complete React frontends from platform-independent GUI models, and AI-assisted modeling supports software with embedded AI components. BESSER connects through an MCP server to Claude Desktop, Cursor, and other MCP-aware clients; BESSER Skills also integrate with Claude Code, Cursor, and Copilot for model and code-generation workflows. Generated Docker components can be used to deploy a running application from a model. The project is MIT-licensed and free, with no freemium tier or hidden fees. It runs on the web, Linux, macOS, and Windows. The Python package installs with pip, and the full codebase can run locally for extensions and generators. It is tested on Python 3.10, 3.11, and 3.12; Python 3.13 is not supported yet. Support includes an on-page assistant, email, and weekly GitHub bug triage.
UMLet
UMLet is a free, open-source tool for quickly sketching UML diagrams, including class, use case, sequence, state, deployment, and activity diagrams. Users edit diagram elements by changing text in a small markup dialect rather than configuring pop-up dialogs. UMLet is available as a stand-alone desktop application, an Eclipse plugin, the browser app UMLetino, and a Visual Studio Code extension. The desktop application exports to BMP, EPS, GIF, JPG, PDF, PNG, and SVG, can copy diagrams to the clipboard, and supports command-line batch conversion of UXF files. UMLetino runs in a browser without installation, stores diagrams in browser storage, and exports PNG. Custom elements can be made with Java code that UMLet compiles on the fly, but only in the stand-alone version. The desktop application requires Java and runs on Java platforms such as Windows, Linux, and macOS. UMLet identifies its license as GNU GPL 3.0. It does not generate code from models or reverse-generate models from code; round-trip engineering is not planned.