01 Charts — TradingView Lightweight Charts™
Every chart in the app is drawn by TradingView Lightweight Charts, version 5.2.1, used under the Apache License 2.0. Its notice, reproduced as the licence asks:
TradingView Lightweight Charts™ Copyright (c) 2025 TradingView, Inc. https://www.tradingview.com/
Source: github.com/tradingview/lightweight-charts. The small TradingView mark on each chart is the library's own attribution. FreeBacktest is not affiliated with, endorsed by or sponsored by TradingView.
02 Local storage — Dexie.js
The app keeps your offline data in the browser with Dexie.js, version 4.4.4, used under the Apache License 2.0. Its notice:
Dexie.js
Copyright (c) 2014-2017 David Fahlander
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
03 Everything else your browser receives
| Library | Version | Licence |
|---|---|---|
| React, React DOM | 18.3.1 | MIT |
| Zustand | 4.5.7 | MIT |
| Yjs | 13.6.32 | MIT |
| y-protocols | 1.0.7 | MIT |
| lib0 | 0.2.117 | MIT |
| Sentry SDK for React | 10.74.0 | MIT |
| Lucide icons | 0.468.0 | ISC |
| Paddle.js | 1.6.5 | Apache 2.0 |
Each licence keeps its copyright holder's name attached to the code; the full texts are at the links above.
04 Fonts
Inter — Copyright 2020 The Inter Project Authors. JetBrains Mono — Copyright 2020 The JetBrains Mono Project Authors. Both are used under the SIL Open Font License, Version 1.1: Inter licence · JetBrains Mono licence.
They are served from this site, not from Google, so loading a page does not send your address to a third party just to draw letters.
05 Something missing or wrong?
If you maintain one of these projects and something here is not as your licence asks, write to hello@freebacktest.app and it will be fixed.