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Archived version ·
pinned v2026-06-01
Reference · Terrestream Indoor Air Quality Sensor
Open-Source Software Notices
Effective June 1, 2026 · Version 1.1 · Operational reference; the Terms of Service control.
This page is the open-source attribution notice referenced by §3.5 of the Terms of Service. It identifies the third-party open-source software components incorporated in the firmware of the Terrestream Indoor Air Quality Sensor (the “ Device ”) at v4.0 and in the Terrestream iOS application (the “App”), together with the license under which each component is used. The Terms of Service control; this page is operational reference material only.
⚠️ Convenience-only reproduction; no warranty
The component identifications, license labels, and links provided on
this page are reproduced from the upstream maintainers’
publications for User convenience only. Aerodyne Inc. does not
author, control, or maintain the upstream license documents and
makes no representation or warranty, express or implied, as to their
accuracy, completeness, currency, or authenticity. The authoritative
license text for each component is the
LICENSE
(or equivalent) file distributed by the upstream maintainer.
The
non-reliance, no-extrinsic-representation, and limitation-of-liability
provisions of the Terms of Service (including, without limitation,
§§ 7, 14, and 15) apply to this page in full.
Incorporated components (Device firmware v4.0)
| Component | Copyright holder | Version | License | Upstream |
|---|---|---|---|---|
| ESP-IDF (Espressif IoT Development Framework) | Espressif Systems (Shanghai) Co., Ltd. | 5.5.4 | Apache-2.0 | github.com/espressif/esp-idf |
| FreeRTOS (bundled with ESP-IDF) | Amazon Web Services / Real Time Engineers Ltd. | (per ESP-IDF 5.5.4) | MIT | freertos.org |
| lwIP (bundled with ESP-IDF) | Swedish Institute of Computer Science (SICS) and contributors | (per ESP-IDF 5.5.4) | BSD-3-Clause (modified) | savannah.nongnu.org/projects/lwip |
| Mbed TLS (bundled with ESP-IDF) | Arm Limited | (per ESP-IDF 5.5.4) | Apache-2.0 (elected from dual) | github.com/Mbed-TLS/mbedtls |
| esp-dsp | Espressif Systems (Shanghai) Co., Ltd. | 1.6.0 | Apache-2.0 | github.com/espressif/esp-dsp |
| led_strip | Espressif Systems (Shanghai) Co., Ltd. | 3.0.1 | Apache-2.0 | components.espressif.com/components/espressif/led_strip |
| esp-nimble-cpp | h2zero and contributors | 2.5.0 | Apache-2.0 | github.com/h2zero/esp-nimble-cpp |
| littlefs (ESP-IDF component) | Brian Pugh (component wrapper); ARM Limited and contributors (LittleFS core) | 1.20.1 | MIT (wrapper); BSD-3-Clause (LittleFS core) | github.com/joltwallet/esp_littlefs |
| AceCommon | Brian T. Park | (as bundled at firmware v4.0) | MIT | github.com/bxparks/AceCommon |
| AceSorting | Brian T. Park | (as bundled at firmware v4.0) | MIT | github.com/bxparks/AceSorting |
| AceTime | Brian T. Park | (as bundled at firmware v4.0) | MIT | github.com/bxparks/AceTime |
| Adafruit BMP3XX Library | Bosch Sensortec GmbH (original) · Adafruit Industries (Arduino port) | (as bundled at firmware v4.0) | BSD-3-Clause | github.com/adafruit/Adafruit_BMP3XX |
| Adafruit BusIO | Adafruit Industries | (as bundled at firmware v4.0) | MIT | github.com/adafruit/Adafruit_BusIO |
| Adafruit Unified Sensor | Adafruit Industries | (as bundled at firmware v4.0) | Apache-2.0 | github.com/adafruit/Adafruit_Sensor |
| ArduinoJson | Benoît Blanchon | (as bundled at firmware v4.0) | MIT | github.com/bblanchon/ArduinoJson |
| LovyanGFX | lovyan03 (Yuji Kuwabara) and contributors; Adafruit Industries (Adafruit_GFX-derived portions) | (as bundled at firmware v4.0) | FreeBSD (BSD-2-Clause) | github.com/lovyan03/LovyanGFX |
| Sensirion Core (Arduino I²C core) | Sensirion AG | (as bundled at firmware v4.0) | BSD-3-Clause | github.com/Sensirion/arduino-core |
| Sensirion I²C SCD4x driver | Sensirion AG | (as bundled at firmware v4.0) | BSD-3-Clause | github.com/Sensirion/arduino-i2c-scd4x |
| Sensirion I²C SEN66 driver | Sensirion AG | (as bundled at firmware v4.0) | BSD-3-Clause | github.com/Sensirion/arduino-i2c-sen66 |
Incorporated components (iOS application v1.0)
The App incorporates the following third-party open-source packages,
pinned at the versions shown by the App’s committed dependency
manifest. Versions advance with App releases; the manifest of record
for any given App build is the Package.resolved file
shipped in that build’s source archive.
| Component | Copyright holder | Version | License | Upstream |
|---|---|---|---|---|
| Firebase Apple SDK | Google LLC | 12.17.0 | Apache-2.0 | github.com/firebase/firebase-ios-sdk |
| Firebase App Check SDK | Google LLC | 11.3.1 | Apache-2.0 | github.com/google/app-check |
| Google Sign-In for iOS | Google LLC | 9.2.0 | Apache-2.0 | github.com/google/GoogleSignIn-iOS |
| Lottie for iOS | Airbnb, Inc. | 4.6.1 | Apache-2.0 | github.com/airbnb/lottie-ios |
| AppAuth for iOS | OpenID Foundation / Google LLC | 2.1.0 | Apache-2.0 | github.com/openid/AppAuth-iOS |
| GTMAppAuth | Google LLC | 5.0.0 | Apache-2.0 | github.com/google/GTMAppAuth |
| GTM Session Fetcher | Google LLC | 3.5.0 | Apache-2.0 | github.com/google/gtm-session-fetcher |
| GoogleDataTransport | Google LLC | 10.1.0 | Apache-2.0 | github.com/google/GoogleDataTransport |
| GoogleUtilities | Google LLC | 8.1.0 | Apache-2.0 | github.com/google/GoogleUtilities |
| Interop for Google SDKs | Google LLC | 101.0.0 | Apache-2.0 | github.com/google/interop-ios-for-google-sdks |
| Abseil C++ (binary distribution) | Google LLC | 1.2024072200.0 | Apache-2.0 | github.com/google/abseil-cpp-binary |
| gRPC (binary distribution) | Google LLC | 1.69.1 | Apache-2.0 | github.com/google/grpc-binary |
| LevelDB | Google LLC | 1.22.5 | BSD-3-Clause | github.com/firebase/leveldb |
| nanopb | Petteri Aimonen and contributors | 2.30910.1 | zlib | github.com/firebase/nanopb |
| Promises | Google LLC | 2.4.1 | Apache-2.0 | github.com/google/promises |
The App additionally embeds two Google-published SDK binaries that are not open-source software and are therefore listed here for transparency only: GoogleAppMeasurement (12.17.0) and the Google Ads On-Device Conversion SDK (3.6.1), each distributed under Google’s own SDK terms. Their inclusion is governed by the Privacy Notice, not by this page.
Per-firmware-version archives
The notices on this page describe the firmware version currently
shipping. For every firmware release from v4.0.37 onward, a
version-stamped archive of the same notices (this
index.html
plus the
licenses/
subdirectory) is published alongside the firmware itself at
api.terrestream.com. The archive is per-version,
immutable, and cached at the edge for 24 hours.
Current firmware:
v4.0.72 ·
download oss-notices-v4.0.72.tar.gz
(approximately 40–50 KB).
URL pattern:
https://api.terrestream.com/firmware/oss-notices-v<VERSION>.tar.gz.
Substitute the firmware version You are running (for example,
v4.0.37) to retrieve the archive for that exact release.
Firmware versions earlier than v4.0.37 do not have a matching
archive published; for those releases, this page is the canonical
public reference.
Mbed TLS dual-license election
Mbed TLS is offered by its maintainer (Arm Limited) under a dual
Apache License 2.0 OR GPL-2.0-or-later
license; each recipient elects one of the two licenses for its use.
Aerodyne elects the Apache-2.0 branch
of that dual license for the firmware release identified on this
page. The GPL-2.0-or-later branch is not invoked, and no
GPL-2.0-or-later obligation (including source-code distribution
under GPL-2.0 §3) applies to Aerodyne’s incorporation of
Mbed TLS in the firmware. The full text of both license options is
included in the upstream
LICENSE
file at
github.com/Mbed-TLS/mbedtls/blob/main/LICENSE.
License texts
The full license text for each component is included with the component’s source distribution and may be obtained from the upstream URL identified in the components table above.
Canonical reference texts for the principal license families used in the Device firmware are available at:
- Apache License, Version 2.0 — apache.org/licenses/LICENSE-2.0
- MIT License (Expat) — opensource.org/license/mit
- BSD 3-Clause “New” or “Revised” License — opensource.org/license/bsd-3-clause
- BSD 2-Clause “Simplified” (FreeBSD) License — opensource.org/license/bsd-2-clause
Updates and version history
This page is republished with each firmware release that materially adds, removes, or upgrades an incorporated open-source component. Prior versions are preserved at /legal/archive.
- June 1, 2026 · v1.1. Initial publication. Scope: Device firmware v4.0 only.
Cross-references
- Terms of Service §3.5 — Open-Source Components clause; permissive-licenses-only commitment; license-conflict rule.
- /legal/sensor-compliance — sensor BOM and vendor datasheets (component manufacturers are distinct from open-source contributors).