Ajay A.Private profile: Upwork shows its earnings only to signed-in members, so we check it every few weeks, not daily. MRR here is a rough estimate (Upwork's six-month earnings ÷ months active). Last read Nov 5, 2026.

Embedded Firmware Engineer with 7+ years of hands-on experience building production-ready firmware for ESP32, STM32, PIC32, and nRF52-based systems. I've delivered real-world solutions for IoT, industrial automation, consumer electronics, smart displays, and connected devices—from proof-of-concept prototypes to mass-production products. My expertise covers low-level firmware, communication protocols, RTOS-based applications, touchscreen interfaces, OTA updates, custom bootloaders, and hardware bring-up. I focus on writing reliable, maintainable, and scalable firmware that performs well in real-world environments. 🎯 Core Technical Expertise • Embedded C/C++ Firmware Development • Bare-Metal, HAL and RTOS-Based Systems • FreeRTOS Integration and Optimization • Hardware Bring-Up and Board Support Packages (BSP) • Device Drivers and Peripheral Development • System Architecture and Firmware Design • Debugging, Profiling, and Performance Optimization • Low-Power Battery-Powered Devices • Production Testing 🎯 Core Expertise • Microcontrollers ESP32 | ESP8266 | STM32F1/F4/F7/H7 | PIC16/18/24/32 | nRF52840 | ARM Cortex M0/M3/M4/M7 | ATmega | RISC-V • Languages C | C++ | Assembly | Python • Wireless WiFi 802.11 b/g/n | Bluetooth Classic | BLE 4.0/5.0/5.1 | Zigbee | Z-Wave | LoRaWAN | NB-IoT | LTE-M | 4G/LTE | 5G | NRF24L01 • IoT Protocols MQTT | CoAP | HTTP/HTTPS | Modbus RTU/TCP | CANbus | RS485 | RS232 | Ethernet | 6LoWPAN • Cloud Platforms AWS IoT Core | Google Cloud IoT | Azure IoT Hub | Firebase | ThingSpeak | Blynk | MQTT (Mosquitto, HiveMQ) • Operating Systems FreeRTOS • Security TLS/SSL | AES-256 | RSA-2048 | ECDSA | SHA-256 | Secure Boot | OTA Authentication | Digital Signatures • Interfaces SPI | I2C | UART | JTAG | OneWire | USB | Ethernet | PWM | ADC/DAC | CAN • Tools STM32CubeIDE | Keil MDK | MPLAB X | Arduino IDE | PlatformIO | VS Code | Git • Sensor Integration DHT11/22 | DS18B20 | BME280 | MPU6050/9250 | HC-SR04 | VL53L0X | INA219 | MQ-series | BH1750 • Motor Control DC motors | Servo motors | Stepper motors (microstepping) | PWM | H-bridge | Relay control | LED/RGB • Power Management Deep sleep modes | Low-power design | Battery optimization (6-24 months runtime) | Voltage regulation | BMS integration | <10µA standby 🎯 GUI & HMI Development • LVGL (Light and Versatile Graphics Library) • Touchscreen Integration (GT911, CST328, and others) • TFT LCD Displays • Custom Widgets and Animations • Industrial HMI Interfaces • Smart Home Control Panels • Real-Time Data Visualization Dashboards 🎯 OTA Update Specialist • Protocols HTTP/HTTPS OTA | MQTT OTA | AWS IoT Jobs | Google Cloud OTA | Azure IoT Hub | BLE OTA | LoRaWAN | Custom protocols • Security Firmware signing (RSA-2048, ECDSA) | AES-256 encryption | SHA-256 verification | Secure boot | Rollback protection • Features Resumable downloads | Dual-partition | Automatic rollback | Compression (gzip) | Progress monitoring | Batch deployment | Version control 🎯 Custom bootloaders • Types UART serial | USB DFU | Network (Ethernet/WiFi) | BLE/LoRa wireless | Secure bootloader (production) | Multi-image A/B | SPIFlash bootloader • Security RSA/ECDSA signatures | CRC32/SHA256 checksums | AES-256 decryption | Anti-rollback | Hardware-backed key storage | OTP regions • Processors ESP32 | STM32 | PIC32 | ARM Cortex-M (all variants) 🎯 Why Clients Prefer Working With Me • 7+ years real-world experience | Not theoretical • End-to-end expertise | Firmware → cloud → security • Security-first | Encrypted comms, secure boot, OTA auth • Hardware-software co-design | Works with your constraints • Power optimization | 6-24 months battery life • Production-grade code | Error handling, logging, testing • Performance tuned | <50ms latency, memory optimized • Post-launch support | Bug fixes, field debugging 🎯 What I Deliver ✔ Custom firmware development (ESP32, STM32, PIC32 ...) ✔ IoT device development (WiFi, BLE, LoRaWAN, NB-IoT connectivity) ✔ Microcontroller programming (all major platforms) ✔ Embedded GUI/HMI (LVGL touchscreen interfaces) ✔ OTA firmware updates (secure, multi-protocol) ✔ Custom bootloaders (secure boot, recovery) ✔ Sensor integration (50+ sensor types) ✔ Motor control systems (DC, servo, stepper) ✔ Power optimization (battery life extension) ✔ Real-time systems (FreeRTOS, RTOS optimization) ✔ Cloud integration (AWS, Google Cloud, Azure) ✔ Security implementation (encryption, auth, secure boot) ✔ Hardware drivers (display, peripheral libraries) ✔ Testing & debugging (unit tests, field debugging) ✔ Technical documentation Let's build production-ready IoT devices that work reliably in the real world.