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CO2-Gadget — Advanced Firmware for ESP32 CO₂ Monitors

CO2-Gadget is an advanced, feature-rich firmware for ESP32-based CO₂ monitors and air quality meters. It supports a wide range of CO₂ sensors, particulate matter (PM) sensors, environmental sensors, displays (TFT, OLED, E-Ink), and communication protocols (WiFi, BLE, MQTT, ESP-NOW). Whether you're building a custom air quality monitor or flashing a commercial board, CO2-Gadget offers enterprise-grade features in a compact embedded package.

Current version: v0.16.015-beta — development branch. See CHANGELOG.md for full release history.

This repository is primarily aimed at developers and advanced users. If you're an end user looking to install the firmware on your device, visit the CO2 Gadget page for pre-built binaries, one-click browser installation, and detailed guides — no compilation required.

📚 Guides available: WiFi, MQTT & Home Assistant, BLE/MyAmbiance, ESP-NOW, Low Power, Calibration, Outputs, Web UI, Sensors, Installation (Spanish, English coming soon).

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✨ Features

🅲 CO₂ & Air Quality Monitoring

• 7+ CO₂ sensor families — Sensirion SCD30/SCD40/SCD41, Senseair S8 LP, Winsen MH-Z19 (A/B/C/D/E), Cubic CM1106 & CM1106SL-NS (ultra-low power)
• Particulate matter (PM) — auto-detected via CanAirIO sensorlib (SPS30, SN-GCJA5, Plantower, SDS011, IKEA Vindriktning, etc.); PM1.0, PM2.5, PM4.0, PM10 published via MQTT with Home Assistant Discovery
• Environmental sensors — BME280, BMP280, BME680, SHT31, AHT10, AM2320, and more
• Sensor auto-detection via CanAirIO sensorlib — plug and play

🖥️ Display Support

• TFT color displays — ST7789 (135×240, 240×240, 320×170), ST7735
• OLED displays — SSH1106, SSD1306 (128×64 I2C)
• E-Ink displays — DEPG0213BN (2.13″), GDEM0213B74 (2.13″), GDEW0213M21 (2.13″), GDEM029T94 (2.9″), GDEH0154D67 (1.54″), GDEM029C90 (2.9″)
• Fully functional without display — all features accessible via web UI, serial, BLE, or MQTT

🌐 Web User Interface — Apple-Inspired Design

Premium web UI hosted directly on the ESP32 with:

• Dark/light mode with system preference auto-detection and manual toggle (persisted via localStorage)
• Responsive design — hamburger nav on mobile, fluid layout on desktop
• Card-based layout with subtle shadows, rounded corners, and Apple-style typography
• Interactive charts page — historical CO₂/temperature/humidity data with date filtering and CSV/JSON export (powered by Chart.js)
• Dedicated calibration page — live CO₂ readings with Forced Re-Calibration (FRC) form
• Low Power configuration page — 4-tab interface for Display, Bluetooth, MQTT, and ESP-NOW thresholds
• Status page with colored feature badges, RSSI, uptime, and real-time sensor values
• SVG tooltip icons — consistent rendering across all browsers
• TFT screenshot capture — web endpoint GET /screenshot for remote display debugging

🔋 Low Power & Deep Sleep

Two power modes, switchable at runtime without reboot:

• HIGH_PERFORMANCE — continuous operation, no deep sleep, all radios active
• LOW_POWER — deep sleep with configurable wake cycles, per-cycle WiFi/BLE/MQTT enable
  • Configurable wait time before first deep sleep entry
  • WiFi connect every N cycles (save power between MQTT publishes)
  • Display redraw every N cycles
  • Wake-up reason tracking (timer, GPIO, touchpad)
  • Boot and wake counters preserved in RTC memory
  • Automatic display off on battery with configurable timeout
  • Wake display on CO₂ alert when crossing the warning threshold
• TDISPLAY_S3 deep sleep validated with ESP32-S3 deep sleep support
• TTGO T-Display power sequencing optimized for minimal deep sleep current
• RTC memory corruption workaround — wake flags reloaded from NVS on every wake cycle

📡 Communication Protocols

Protocol	Function
WiFi	Web server (REST API), MQTT, OTA updates, Captive Portal
BLE	Sensirion MyAmbiance App (iOS/Android) — real-time data, history download, WiFi configuration, SCD4x calibration
BTHome v2	Home Assistant BLE auto-discovery — zero-config, no MQTT/WiFi needed. Encrypted (AES-CCM), wake-aware, 10 selectable measurements with smart byte-budget. Independently togglable from Sensirion MyAmbiance.
MQTT	Publish measurements, battery, alarms; receive remote commands; Home Assistant Discovery (auto-config)
ESP-NOW	Long-range, low-power Espressif protocol for mesh/gateway setups
HTTP/REST	Full web API for configuration, sensor data, system status
Improv Serial	One-step WiFi configuration from serial terminal
Captive Portal	WiFi setup via browser on first boot

🔧 Configuration & Management

• On-screen menu — full device configuration via push buttons (TFT/OLED/E-Ink)
• Web-based management — all settings configurable from any browser
• Serial console — text-based menu over USB
• BLE configuration — WiFi credentials and calibration from MyAmbiance App
• MQTT remote commands — calibration and pressure settings over the air
• ThresholdManager library — NVS-persisted thresholds (absolute + percentage) for CO₂, temperature, humidity; gates MQTT/BLE/ESP-NOW publishing to save bandwidth and power

📊 Calibration

• Datasheet-compliant warm-up sequence — per-sensor warm-up (readings + time) before applying field calibration
• Forced Re-Calibration (FRC) — via web page, serial menu, on-screen menu, BLE, or MQTT (400–2000 ppm range)
• Ambient pressure compensation — SCD30 and SCD4x with mbar/hPa support
• Calibration warm-up across deep sleep — progress preserved in RTC across sleep cycles
• CM1106 continuous mode — pauses deep sleep automatically during calibration (needs continuous operation)

🎵 Outputs

• Unified output system — CO2_Gadget_Outputs.h (single include for Buzzer, NeoPixel, GPIO relays)
• GPIO relays — configurable orange/red threshold outputs with hysteresis
• RGB LEDs — color-coded air quality indication
• NeoPixel (WS2812B) — addressable RGB/RGBW LED strips (configurable count)
• Buzzer — configurable tone (300–2000 Hz) and duration (50–300 ms) for CO₂ level alerts
• Hysteresis — prevents output chatter (configurable PPM thresholds)

🔄 OTA Updates

• Over-the-air firmware updates via ElegantOTA (async mode)
• Web-based upload from the Preferences page (Maintenance card)

📈 Data Logging

• Circular buffer — in-memory data history for web charts (configurable capacity up to 1440 samples)
• BLE history — downloadable via MyAmbiance App to smartphone (configurable interval)
• CSV/JSON export — from the web Charts page
• Configurable intervals — measurement, sampling, history, and MQTT publish intervals independently configurable
• Accumulated uptime — retained across deep sleep cycles (not reset on wake)

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🧰 Supported Hardware

ESP32 Boards

The project supports multiple ESP32 boards with pre-configured GPIO mappings. Adding support for a new board is straightforward — just define the pins in platformio.ini.

Flavor	Chip	Display	Notes
TTGO_TDISPLAY	ESP32	TFT 240×135 (ST7789)	Compact all-in-one with buttons, battery support
TTGO_TDISPLAY_SANDWICH	ESP32	TFT 240×135 (ST7789)	Sandwich board variant (I2C swapped)
TDISPLAY_S3	ESP32-S3	TFT 320×170 (ST7789)	USB CDC, PSRAM, DW8904 backlight IC
esp32dev	ESP32	None	Generic dev board, headless operation
esp32dev_OLED	ESP32	OLED 128×64 (SSH1106)	Generic board with I2C OLED
esp32dev-ST7789_240x320	ESP32	TFT 240×320 (ST7789)	Larger TFT on dev board
ttgo-t5-EINKBOARDGDEM0213B74	ESP32	E-Ink 2.13″ (GDEM0213B74)	LilyGO T5 variant
ttgo-t5-EINKBOARDDEPG0213BN	ESP32	E-Ink 2.13″ (DEPG0213BN)	LilyGO T5 with DEPG0213BN
ttgo-t5-EINKBOARDGDEW0213M21	ESP32	E-Ink 2.13″ (GDEW0213M21)	LilyGO T5 with GDEW0213M21
ttgo-t7-EINKBOARDGDEM029T94	ESP32	E-Ink 2.9″ (GDEM029T94)	LilyGO T7 with GDEM029T94
ttgo-t7-WEACT_GDEH0154D67	ESP32	E-Ink 1.54″ (GDEH0154D67)	WeAct Studio 200×200
ttgo-t7-WEACT_DEPG0213BN	ESP32	E-Ink 2.13″ (DEPG0213BN)	WeAct Studio 250×122
ttgo-t7-WEACT_GxEPD2_290_BS	ESP32	E-Ink 2.9″ (GDEM029C90)	WeAct Studio 296×128

GPIO Pin Mapping

Flavor	RX/TX	I2C SDA/SCL	UP/DWN	GPIO Orange	GPIO Red	Battery	Neopixel	Buzzer
TTGO_TDISPLAY	13/12	21/22	35/0	32	33	34	26	2
TTGO_TDISPLAY_SANDWICH	13/12	22/21	35/0	32	33	34	26	2
TDISPLAY_S3	18/17	43/44	14/0	3	1	4	16	2
esp32dev_OLED	17/16	21/22	15/0	32	33	34	26	2
esp32dev	17/16	21/22	15/0	32	33	34	26	2
esp32dev-ST7789_240x320	17/16	21/22	19/0	32	33	34	26	2
ttgo-t5-* (E-Ink)	15/14	21/22	-1/-1	32	33	35	26	2
ttgo-t7-* (E-Ink)	15/14	21/22	-1/-1	32	33	35	26	2
ttgo-t7-WEACT_* (E-Ink)	15/14	21/22	-1/-1	32	33	35	26	2

• RX/TX: Pins for UART sensors (MH-Z19, CM1106, Senseair S8, etc.)
• I2C SDA/SCL: I²C bus for sensors and displays
• UP/DWN: Button pins (optional, firmware is fully functional without buttons)
• GPIO Orange/Red: Output pins for relays, alarms, and RGB LEDs at threshold levels
• Battery: ADC pin for battery voltage measurement
• Neopixel: Data pin for WS2812B addressable LEDs
• Buzzer: Pin for passive piezo buzzer (built-in transistor recommended)

Display Types

Supported Sensors

Sensor support is provided by CanAirIO sensorlib — sensors are auto-detected on boot (plug and play). Thanks to @hpsaturn and the CanAirIO team!

CO₂ Sensors

Sensor	Interface	Detection	Status
Sensirion SCD30	I²C	Auto	✅ STABLE
Sensirion SCD40 / SCD41	I²C	Auto	✅ STABLE
Winsen MH-Z19 (A/B/C/D/E)	UART	Select	✅ STABLE
Cubic CM1106 / CM1106SL-NS	UART	Select	✅ STABLE (incl. ultra-low power mode)
Senseair S8 LP	UART	Select	✅ STABLE

Particulate Matter (PM) Sensors

Auto-detected via CanAirIO; PM1.0, PM2.5, PM4.0, PM10 variables published via MQTT with Home Assistant Discovery.

Sensor	Interface	Detection	Status
Sensirion SPS30	UART / I²C	Select / Auto	✅ STABLE
Panasonic SN-GCJA5	UART / I²C	Auto	✅ STABLE
Plantower models (PMS x003)	UART	Auto	✅ STABLE
Nova SDS011	UART	Auto	✅ STABLE
IKEA Vindriktning	UART	Select	✅ STABLE

Environmental Sensors

Sensor	Interface	Detection	Status
BME280, BMP280	I²C	Auto	✅ STABLE
BME680 (IAQ)	I²C	Auto	✅ STABLE
SHT31	I²C	Auto	✅ STABLE
AHT10	I²C	Auto	✅ STABLE
AM2320	I²C	Auto	✅ STABLE
DFRobot SEN0469 (NH₃)	I²C	Auto	🧪 TESTING
DFRobot SEN0466 (CO)	I²C	Auto	🧪 TESTING
Geiger CAJOE	I²C	Select	🧪 TESTING
DHTxx	TwoWire	Auto	⚠️ DEPRECATED

Note: DHT22 is supported but not recommended due to accuracy limitations.

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🚀 Installing

One-Click Browser Installation (End Users)

Visit the CO2 Gadget page — no software installation required. Just connect your board via USB, click the installer button, and follow the prompts. The firmware is uploaded in seconds directly from your browser.

Building from Source (Developers)

Prerequisites

• PlatformIO (CLI or VSCode extension) — recommended
• Git

Setup

1. Clone the repository:

   git clone https://github.com/melkati/CO2-Gadget.git
   cd CO2-Gadget

2. Configure your board ports (optional): create platformio_extra_configs.ini in the project root with your local COM ports:

   [common_env_data]
   upload_port = COM13        # Your board's USB port
   monitor_port = COM13       # Your board's USB port

   This file is .gitignore'd — each developer keeps their own ports without affecting the repo. All environments in platformio.ini reference the common_env_data variables. If you have multiple boards on different ports, add per-environment overrides:

   [env:ttgo-t5-EINKBOARDDEPG0213BN]
   upload_port = COM6
   monitor_port = COM6

3. Rebuild web assets (required after editing any file in webserver/):

   powershell -ExecutionPolicy Bypass -File webserver/MinifyCompressAllFiles.ps1 -DeleteMinifiedFiles

   Since PR #296, extra_scripts in platformio.ini runs tools/prebuild_web_assets.py before each build, which detects stale .gz files in data/ and runs the pipeline automatically when needed. Note: Requires PowerShell (pwsh or powershell). pwsh (PowerShell 7) is available on all platforms including macOS/Linux. Install it via: winget install Microsoft.PowerShell (Windows), brew install powershell (macOS), or apt install powershell (Linux). You can also always run the pipeline manually for immediate results.

4. Build and upload (replace TTGO_TDISPLAY with your desired flavor):

   pio run -e TTGO_TDISPLAY --target upload

5. Monitor serial output:

   pio run -e TTGO_TDISPLAY --target monitor

   Or use PlatformIO's Upload and Monitor task from the VS Code GUI.

Note: Arduino IDE is not officially supported. Use PlatformIO for building from source.

---

🌐 Web Interface

Once connected to WiFi, open the device's IP address in any browser. The interface adapts to dark/light mode automatically.

Page	URL	Description
Home	/	Real-time CO₂, temperature, humidity dashboard
Charts	/charts.html	Historical data with interactive graphs, date filter, CSV/JSON export
Calibration	/calibration.html	Live CO₂ readings and FRC calibration form
Low Power	/low_power.html	Configure deep sleep thresholds (Display, BLE, MQTT, ESP-NOW)
Preferences	/preferences.html	Full device settings (gear icon in navbar)
Status	/status.html	System status, versions, uptime, network info
OTA Update	/update	Firmware upload (via Preferences → Maintenance card)
Screenshot	/screenshot	TFT display screenshot (PNG) — useful for remote debugging

---

📱 Mobile App (BLE)

CO2-Gadget works with the Sensirion MyAmbiance app for iOS and Android:

• Real-time CO₂, temperature, and humidity visualization
• Historical data charts and download to phone
• WiFi configuration via BLE
• Sensor calibration commands

🏠 Home Assistant BLE (BTHome)

CO₂ Gadget also emits standard BTHome v2 advertisements that Home Assistant auto-discovers — no MQTT, no WiFi, no cloud.

• HA BLE auto-discovery with entity creation
• 10 selectable measurement types: CO₂, Temperature, Humidity, Battery (% and mV), Pressure, PM1.0/PM2.5/PM4.0/PM10 — granular selection in Web UI and serial menu
• Optional AES-CCM encryption with auto-generated bind key, configurable via Web UI (Reveal/Copy/Regenerate) and serial menu
• Low-power-aware: PM omitted on deep sleep; pressure on wake requires opt-in build flag
• Fully independent from Sensirion MyAmbiance — both can be active simultaneously

---

🏗️ Project Structure

CO2-Gadget/
├── CO2_Gadget.ino              # Main firmware entry point & setup()
├── CO2_Gadget_Sensors.h        # Sensor initialization, reading callbacks, PM variables
├── CO2_Gadget_Battery.h        # Battery voltage reading and level calculation
├── CO2_Gadget_Outputs.h        # Unified outputs (Buzzer + NeoPixel + GPIO relays)
├── CO2_Gadget_Buzzer.h         # Piezo buzzer driver
├── CO2_Gadget_Neopixel.h       # WS2812B addressable LED driver
├── CO2_Gadget_Preferences.h    # NVS preferences persistence (save/load/JSON import-export)
├── CO2_Gadget_Thresholds.h     # ThresholdManager for gated publishing
├── CO2_Gadget_DeepSleep.h      # Low power / deep sleep management
├── CO2_Gadget_Menu.h           # On-screen menu system (ArduinoMenu library)
├── CO2_Gadget_Buttons.h        # Push button handling (Button2 library)
├── CO2_Gadget_WIFI.h           # WiFi + Web server + REST API + Captive Portal
├── CO2_Gadget_Improv.h         # Improv WiFi serial configuration
├── CO2_Gadget_BLE.h            # BLE (Sensirion MyAmbiance App)
├── CO2_Gadget_BTHome.h         # BTHome v2 BLE advertising (encoding, encryption, budget)
├── CO2_Gadget_MQTT.h           # MQTT client + Home Assistant Discovery
├── CO2_Gadget_ESP-NOW.h        # ESP-NOW communication
├── CO2_Gadget_TFT.h            # TFT display driver (TFT_eSPI)
├── CO2_Gadget_OLED.h           # OLED display driver (U8g2)
├── CO2_Gadget_EINK.h           # E-Ink display driver (GxEPD2)
├── CO2_Gadget_CircularBufferManager.h  # Rolling data buffer for web charts
├── platformio.ini              # Build configuration, flavors, features, pins
├── CO2_Gadget_Partitions.csv   # Custom flash partition table (for BLE + SPIFFS)
├── libs/
│   └── CO2_Gadget_Thresholds/  # Threshold manager library with NVS persistence
├── webserver/                  # Web UI source files (HTML, JS, CSS) + minification scripts
├── data/                       # Compiled SPIFFS data (minified + gzipped web assets)
├── docs/BTHome.md              # BTHome technical reference (payload, encryption, deep sleep)
└── docs/                       # Architecture and development documentation

---

⚙️ Build Configuration

Enabling/Disabling Features

Edit platformio.ini under the [features] section. Comment or uncomment any line:

[features]
build_flags =
    -DSUPPORT_BLE              ; BLE / MyAmbiance App
    -DSUPPORT_BTHOME_BLE       ; BTHome v2 BLE advertisements for Home Assistant
    -DSUPPORT_BUZZER           ; Piezo buzzer
    ; -DSUPPORT_ESPNOW         ; ESP-NOW (comment to disable)
    -DSUPPORT_MDNS             ; mDNS hostname resolution
    -DSUPPORT_MQTT             ; MQTT client
    -DSUPPORT_MQTT_DISCOVERY   ; Home Assistant auto-discovery
    -DSUPPORT_OTA              ; Over-the-air updates
    -DSUPPORT_LOW_POWER        ; Deep sleep / low power mode
    ; -DSUPPORT_LOW_POWER_PRESSURE ; BME280 pressure on deep-sleep wake (opt-in, needs BTHome + Low Power)
    -DSUPPORT_CIRCULAR_BUFFER  ; In-memory data buffer for web charts

Build Flavors

Build a specific board flavor:

pio run -e TTGO_TDISPLAY --target upload
pio run -e TDISPLAY_S3 --target upload
pio run -e esp32dev --target upload
pio run -e ttgo-t5-EINKBOARDDEPG0213BN --target upload

All available environments are listed in platformio.ini under [platformio] → default_envs.

Debug Options

Enable debug output by uncommenting flags in the [debug] section:

[debug]
build_flags =
    -DDEBUG_EINK               ; E-Ink display debug
    ; -DDEBUG_NEOPIXEL         ; NeoPixel debug
    ; -DDEBUG_PREFERENCES      ; Print preferences on load/save
    ; -DDEBUG_WIFI_EVENTS      ; WiFi event debug
    ; -DDEBUG_BLE              ; BLE debug
    ; -DDEBUG_THRESHOLDS       ; Threshold evaluation debug
    -DWIFI_PRIVACY             ; Hide passwords in serial output
    -D CORE_DEBUG_LEVEL=0      ; 0=None, 1=Error, 2=Warning, 3=Info, 4=Debug, 5=Verbose

---

🔧 Development & Contributing

Everyone is welcome to contribute to CO2-Gadget, regardless of skill level or background.

Getting Started

1. Fork the repository
2. Create a feature branch: git checkout -b feat/my-feature or git checkout -b fix/my-fix
3. Make your changes — follow the existing code style (Google style, clang-format friendly)
4. Test your changes — ensure builds succeed for at least one flavor
5. Document your code and PR
6. Open a Pull Request targeting the development branch

Guidelines

• Run clang-format (Google style) before committing
• Keep PRs focused on a single feature or fix
• Update CHANGELOG.md with your changes
• For major changes, open an issue first to discuss

AI-Assisted Contributions

We welcome the responsible use of AI tools. See docs/ai-guidelines.md for our full policy.

TL;DR: AI is a productivity tool, not a substitute for understanding. You are responsible for every line of code you submit.

Testing

We have active Alpha and Beta testing programs. Reach out on Telegram.

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📚 Useful Resources

• Everything about the Sensirion SCD30 NDIR dual-channel CO₂ sensor
• Everything about the Sensirion SCD40 and SCD41 RPAS CO₂ sensors
• Everything about the Winsen MH-Z19 NDIR CO₂ sensors
• Everything about the Winsen Low Consumption CO₂ Sensor MH-Z1311A
• MH-Z19B vs Senseair S8 NDIR comparison
• Tutorial: Build a CO₂ Monitor with TTGO T-Display + SCD30
• Tutorial: Compact CO₂ Gadget with battery support
• ESP-NOW to MQTT Gateway
• CO2 Gadget firmware page (Spanish) — installation, guides, FAQ
• CO2 Gadget guides index — all tutorials and documentation
• CanAirIO sensorlib

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📜 License

Copyright (C) 2021-2024 Mariete & CO2 Gadget Contributors · Contact: https://emariete.com

This project is licensed under the GNU General Public License v3.0 — see the LICENSE file for details.

---

🙏 Credits

Thanks to all collaborators, contributors, and the eMariete community for testing, feedback, and support.

Special thanks to:

• CanAirIO team — sensor abstraction library
• All contributors who helped improve CO2 Gadget — you are awesome!

---

⭐ Support the Project

If you find CO2-Gadget useful:

• ⭐ Star this repository on GitHub — it helps others discover the project
• 📢 Share your experience with the community on Telegram
• 🐛 Report bugs or suggest features via GitHub Issues
• 🤝 Contribute code, documentation, or testing

Material donations (hardware for testing) are also appreciated to support further development.

---

If you read this far, please star this repository! ⭐

## License

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▐       ____ ___ ____     ____           _            _        ▌
▐      / ___/ _ \___ \   / ___| __ _  __| | __ _  ___| |_      ▌
▐     | |  | | | |__) | | |  _ / _` |/ _` |/ _` |/ _ \ __|     ▌
▐     | |__| |_| / __/  | |_| | (_| | (_| | (_| |  __/ |_      ▌
▐      \____\___/_____|  \____|\__,_|\__,_|\__, |\___|\__|     ▌
▐                                          |___/               ▌
▐▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▌

Copyright (C) 2021-2026 Mariete & CO2 Gadget Contributors
Contact: https://emariete.com

This file is part of the CO2 Gadget firmware.

The CO2 Gadget firmware is free software: you can
redistribute it and/or modify it under the terms of the GNU Lesser General
Public License as published by the Free Software Foundation, either version
3 of the License, or (at your option) any later version.

The emariete.com Website and Documentation is distributed in the hope
that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the emariete.com Website and Documentation. If not, see
<http://www.gnu.org/licenses/>.

▐▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▌
▐                                _      _                                 ▌
▐       ___ _ __ ___   __ _ _ __(_) ___| |_ ___   ___ ___  _ __ ___       ▌
▐      / _ \ '_ ` _ \ / _` | '__| |/ _ \ __/ _ \ / __/ _ \| '_ ` _ \      ▌
▐     |  __/ | | | | | (_| | |  | |  __/ ||  __/| (_| (_) | | | | | |     ▌
▐      \___|_| |_| |_|\__,_|_|  |_|\___|\__\___(_)___\___/|_| |_| |_|     ▌
▐▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▌