Forms-Engine vs SurveyJS
SurveyJS and Forms-Engine overlap on “dynamic forms with conditional logic, rendered in your web app, data in your database” — but they’re different kinds of product, and the licensing line runs through the middle of SurveyJS.
What SurveyJS is
Section titled “What SurveyJS is”A family of JavaScript libraries. The Form Library — the renderer that displays JSON-defined forms in React, Angular, Vue, or plain JS — is MIT and genuinely excellent: mature, deeply themeable, with a large catalog of question types and very extensive conditional logic. Around it sit the Survey Creator (the drag-and-drop visual builder), PDF Generator, and Dashboard — proprietary components requiring a paid per-developer license for production use. There is no backend: you build the API and storage that serve definitions and receive results.
Where SurveyJS is stronger
Section titled “Where SurveyJS is stronger”- Breadth of the form library. More question types (matrices, panels, dynamic panels, ranking…), more validation options, more themes, more of everything at the rendering layer. Forms-Engine’s twelve types cover common questionnaire ground; SurveyJS covers more.
- Framework depth. First-class React, Angular, and Vue renderers, years of production hardening, a big community, commercial support.
- Total flexibility. Because you own the backend, any storage, workflow, or auth model is yours to build.
Where Forms-Engine differs
Section titled “Where Forms-Engine differs”- The editor is free and included. The visual builder — the part of SurveyJS that carries a commercial per-developer license — is MIT here, along with everything else. Non-developers can build and publish questionnaires without anyone buying a license.
- The backend exists. Definitions, versioning, response storage, file
uploads with content verification, CSV export, rate limiting — with
SurveyJS these are your integration project; here they’re
docker compose up. - Version-pinned responses. Publishing is versioned and every response pins to its version, so editing a live questionnaire never corrupts in-flight sessions or the interpretability of old data. With SurveyJS, schema-vs-old-results consistency is yours to design.
- One embed, framework-agnostic. A single web component (with thin React/Angular wrappers) rather than per-framework renderers.
Honest bottom line
Section titled “Honest bottom line”If you’re a developer building form experiences deep inside your own product and you want maximal client-side capability — SurveyJS’s form library is the stronger toolkit, and if you don’t need the visual builder, its MIT core may be all you need. If what you want is the whole loop — non-developers building questionnaires in a UI, your site embedding them, responses landing versioned in your own MongoDB — without a commercial license anywhere in the stack, that’s the gap Forms-Engine exists to fill.