Embedded Firmware Engineer

Repos Energy; Pune District; On-site; INR 1,200,000 - 2,400,000; Full time

Job summary

Repos in Pune, India is seeking an experienced firmware engineer to build industrial IoT gateways, sensors and edge telemetry units. You will develop firmware for Modbus and CAN interfaces, enable local data processing and reliable telemetry to cloud via BLE, Wi-Fi, 4G/LTE and GPRS.

You will optimize power, handle OTA updates, implement MQTT streaming to AWS/Azure, and ensure data integrity in noisy industrial environments.

Qualifications

• 4–6 years of experience in embedded software or firmware design.
• 2+ years deploying networked IoT products in production industrial environments.
• Bachelor’s or Master’s degree in Electronics and Communication Engineering, Electrical Engineering, IoT or related field.

Responsibilities

• Develop firmware for industrial IoT gateways and edge devices.
• Implement Modbus and CAN communications and MQTT data streaming to cloud.
• Optimize power and bandwidth in cellular/GPRS deployments.
• Design and maintain secure OTA updates and rollback protection.

Skills

Embedded C/C++

Python scripting

MQTT

Security TLS

RTOS familiarity

Edge data processing

Education

Bachelor/Master in Electronics & Communication / Electrical / IoT

Tools

Modbus RTU/TCP

CAN Bus

FreeRTOS

STM32/ESP32

Job description

Role Overview

We are looking for an experienced firmware engineer to build industrial IoT gateways, smart sensors and edge-telemetry units. The role combines firmware development for industrial equipment interfaces (including Modbus and CAN), local data processing, and dependable telemetry delivery to cloud infrastructure over BLE, Wi-Fi, 4G LTE and GPRS.

A key focus is maintaining data integrity and reliable connectivity in bandwidth-constrained, power-sensitive and electromagnetically noisy industrial environments.

Key Responsibilities

1. Wireless Connectivity and Network Management

Integrate wireless communication modules and technologies, including Wi-Fi, Bluetooth Low Energy (BLE 5.0+), 4G LTE and GPRS/2G fallbacks.

Build resilient network-management logic for automated network switching, signal-strength optimization, reconnection state machines and failover paths.

Implement secure over-the-air (OTA) firmware updates over cellular and Wi-Fi, including boot validation and rollback protection.

2. Industrial Protocols and Edge Telemetry

Develop master/slave communication engines using Modbus RTU over RS485/RS232 and Modbus TCP to collect telemetry from industrial energy meters, PLCs and variable-frequency drives (VFDs).

Translate machine registers—including Modbus holding registers and CAN frame IDs—into structured, serialized payloads such as JSON.

Build optimized MQTT clients that manage QoS levels, persistent sessions, keep-alives and retained messages to stream edge data securely to AWS IoT Core, Azure IoT or custom Mosquitto brokers.

3. Edge Data Processing and Storage

Implement local buffering and timestamped logging using SQLite, SD cards or BBRAM to reduce data loss during cellular or Wi-Fi outages.

Optimize power consumption and bandwidth usage in cellular/GPRS deployments through data compression and deadband polling strategies.

Develop edge-computing logic for local decision-making, fast filtering, real-time alert triggers and safe-state management.

4. Firmware Architecture and Microcontroller Development

Build modular, multithreaded bare-metal or RTOS-based firmware, including FreeRTOS, for 32-bit platforms such as STM32, Renesas RA, ARM Cortex, NXP and ESP32.

Manage real-time peripheral tasks alongside network transactions, including UART/SPI/I2C buses, timers, watchdog timers and low-level ADC interfaces.

Technical Skills

Programming: Embedded C, C++, and Python or shell scripting for internal automation and testing tools.

Industrial and Field Protocols: Modbus RTU/TCP, CAN Bus (SocketCAN, bxCAN, J1939, UDS), RS485 and RS232.

IoT and Networking: MQTT, HTTPS, TCP/IP socket programming and JSON serialization.

Wireless and RF: 4G LTE/GPRS cellular AT commands, Wi-Fi (802.11) and BLE profiles, services and advertising.

Operating Systems and Microcontrollers: FreeRTOS, STM32, ARM Cortex-A/M processors and ESP32 (ESP-IDF).

Debugging Tools: Wireshark, PCANView/Vehicle Spy, logic analyzers, GDB and AT-command terminals such as Tera Term.

Security: TLS 1.2/1.3, MQTTS (secure MQTT), cryptographic device authentication and X.509 certificate handling.

Qualifications and Experience

4–6 years of experience in embedded software or firmware design, including at least 2 years focused on deploying networked IoT products in production industrial environments.

Bachelor’s or Master’s degree in Electronics and Communication Engineering, Electrical Engineering, IoT or a closely related discipline.

Experience with remote field-monitoring gateways, smart energy grids, heavy industrial instrumentation or environmental telemetry systems.