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SYS://REZZZ_FLASHER.EXE [ESP8266_D1_MINI]
Open Source · ESP8266 · MIT License

Rezzz Flasher
ESP8266 Travel Router

Turn a $4 Wemos D1 Mini into a pocket-sized NAT travel router. Share hotel or airport Wi-Fi across all your devices, crush captive portals, and inject custom DNS — straight from your browser.

Flash Firmware Now View Source
rezzz-flasher esp8266 wemos-d1-mini travel-router nat-router captive-portal webserial littlefs
Zero-Driver Setup

Rezzz Web Flasher

Plug in your Wemos D1 Mini via USB and flash the latest Rezzz Flasher firmware directly from Chrome or Edge. No CLI, no Arduino IDE required.

Requires Chrome / Edge with WebSerial API (Windows, Linux, macOS).
// CAPABILITIES

Full-featured travel router on a $4 chip

Rezzz Flasher transforms an ESP8266 microcontroller into a rock-solid NAT router. It connects upstream to any Wi-Fi network — including hotel, airport, Airbnb, or public hotspots — and broadcasts a private access point for all your gear.

100% open-source and customizable. Control DNS resolvers, SSID settings, captive portal bypass rules, and routing logic right from the built-in web dashboard.

NAT Routing
Share a single upstream Wi-Fi connection with multiple client devices via full lwIP NAT routing on the ESP8266.
Captive Portal Bypass
Dedicated captive portal detection and bypass logic for hotel Wi-Fi, airport lounges, and public hotspots.
Custom DNS Injection
Inject custom DNS servers for all downstream clients. Apply ad-blocking DNS or private resolvers automatically.
Embedded Web UI
Fast, responsive asynchronous web dashboard for real-time network control and SSID management hosted on-chip.
Persistent LittleFS
All settings are saved in flash via LittleFS. Your SSID, credentials, and DNS configs survive reboots.
1-Click WebSerial
Flash directly from your browser via Rezzz Flasher without installing drivers or compiling code locally.
// TARGET AUDIENCE

Built for travellers, makers & tinkerers

Ever hit a device limit on hotel Wi-Fi or struggled to log in on a headless device behind a captive portal? Rezzz Flasher solves it in seconds.

🏨
Hotel Wi-Fi Sharing
Pay for one connection, share it across all your devices through your own private AP.
✈️
Airport & Lounges
Authenticate the captive portal once on the router, then connect every device seamlessly.
🏕️
Airbnb & Co-Working
Keep a single trusted private SSID on top of untrusted public networks.
🛡️
Custom DNS on the Road
Force all downstream devices to use AdGuard, NextDNS, Cloudflare, or your own resolver.
🔬
IoT & Maker Projects
Use as a lightweight NAT bridge for microcontrollers that need isolated network access.
💻
Network Lab
Experiment with NAT routing, DNS injection, and AP management on $4 hardware.
// TECH SPECS

Under the Hood

Rezzz Flasher targets the ESP8266 SoC on the Wemos D1 Mini (4MB flash). Built on the Arduino ESP8266 core, it requires zero extra components—just a micro-USB cable and a WebSerial-capable browser.

The pre-compiled router.bin is ready for instant flashing. Licensed under MIT.

Tool NameRezzz Flasher
Target HardwareWemos D1 Mini (ESP8266)
Flash Required4 MB
FrameworkArduino / ESP8266
StorageLittleFS (Persistent)
DashboardAsync Web Server
DNSCustom Firmware Injection
Captive PortalDedicated Bypass Logic
LicenseMIT Open Source
// QUICKSTART

Flash in 3 Raw Steps

No Arduino IDE, no terminal commands. Grab a data-capable micro-USB cable and open Chrome or Edge.

01
Plug in your Wemos D1 Mini
Connect the board to your computer using a data micro-USB cable and open Rezzz Flasher in Chrome or Edge.
02
Hit "Connect & Flash Now"
Click the install button above, pick your USB serial port from the popup, and let Rezzz Flasher write the binary automatically.
03
Join the Router AP
Once rebooted, connect to the newly broadcasted Wi-Fi AP, open the dashboard IP, and link your upstream Wi-Fi.

Open Source. Brutally Simple. Ready to Flash.

Explore the full source code, documentation, and issue tracker on GitHub.

Star on GitHub ⚡ Launch Rezzz Flasher