adi
About
I make hardware behave in the field, and I can show you the numbers.
Eight years of embedded systems work, from bare-metal and RTOS firmware on ARM microcontrollers through board bring-up to embedded Linux. Today I own the firmware and services layer for a fleet of more than 500 Debian edge gateways in production across 30 remote sites in 20 states: provisioning, golden images, update and rollback, remote diagnostics, and the root-cause work that cuts across hardware, Linux, networking and protocols when something in the field misbehaves.
Before that: instruments that had to meet functional-safety requirements, battery tracking devices that had to last two years on a cell and pass FCC, and a LoRaWAN stack I helped implement. What ties it together is evidence. A system is reliable when a year of field logs says so, fast when the trace says so, and finished when someone else can build it from the repository.
Track record
Where the eight years went
A fleet that heals itself
Own the services layer for 500+ Debian gateways: Losant provisioning, golden image builds, configuration standards (udev serial naming, Docker Compose service layout, DNS), remote diagnostics and recovery procedures. Redesigned the gateway services for self-healing on connection loss, local-first logging to bound data loss, health telemetry where none existed, and pattern-based alerting ahead of failures: unplanned events fell from 50-60 a week to 4-5, and the rest are physical damage or site power. Built the acquisition services (Python, systemd, Node-RED) for serial and network devices with validation, SQLite buffering, atomic state files, MQTT routing, retries, watchdogs and fault states. Integrated ~150 devices from 9 vendors over Modbus TCP/RTU, EtherNet/IP, RS-232/485 and MQTT/Sparkplug B, and 600+ 900 MHz radios. Delivered 22 sites and 15 distinct use-case integrations in a year, scoping to handoff, coordinating R&D, contractors and vendors. Led a 41-unit weather-transmitter data-quality study across 31 sites, isolating 15 defective units from integration issues and securing vendor RMAs.
Bring-up, functional safety, and a chip shortage
Led board bring-up, firmware and system debugging for monitoring and control hardware used in production and in the field. When the original parts carried 24+ month lead times, selected and qualified alternates with equivalence testing and updated firmware, hardware and test procedures: the main board replacement shipped in 5 months against a 6-month production window, the FPGA board in 12 against 18, with no production gap. Supported a product designed to IEC 61508 parts 2 and 3: validation, documentation, diagnostics, design reviews. Wrote RTOS and bare-metal firmware for ARM: drivers, interrupts, timers, communication interfaces, control logic, production diagnostics. Built the automated manufacturing, calibration and validation test systems.
Two years on a battery, and an antenna that passed
Firmware for ARM-based LoRaWAN trackers used for refrigerated food monitoring: geofencing, location, temperature logging, vibration detection, cloud upload. Integrated the radios, sensors and local storage so data survived intermittent connectivity; implemented LoRaWAN stack features and the gateway-side HTTP/MQTT access with the software team. Owned FCC certification: diagnosed harmonic emissions from the in-house antenna during compliance testing, redesigned it, and certified. Sleep states, sensor duty-cycling, communication scheduling and power-budget analysis to reach 2+ years of battery life.
Where it started
Designed, tested and validated credit-card-sized sub-GHz LPWAN monitoring devices; range, signal quality and RF noise work on the radio modules and circuits.
MS Electrical Engineering, University at Buffalo (SUNY), 2018 · BTech Electronics and Communication, SRM University, 2016
How I work
A few rules I keep coming back to
Bound the damage first.
Local-first logging, atomic state files, watchdogs and recovery paths before features. A gateway that loses its link should lose nothing, and tell you about it when it is back.
Measure before you guess.
Field logs, bench tests, traces and cycle counters. The slow or broken part is rarely where it feels like it is; the fleet's alerting and the watch's 315 to 107 cycles per pixel both came from looking at the numbers first.
Qualify, do not assume.
Replacement parts, vendor claims and AI-generated register maps all get checked against live reads and bench tests before anything goes to production.
Write it down, with the data.
Procedures, configuration standards and write-ups that keep the raw evidence next to the conclusion, so the next engineer, often me, can check the reasoning.
After hours
Side projects, with the receipts
lumo-watch
A dual-core Zephyr smartwatch whose second hand glides at a locked 60 fps, and which doubles as a USB volume knob for the laptop.
- 12 fps with a GUI library to 59, steady; display writes 3.4 ms to 0.5 ms
- Every optimisation has a build switch and a before/after trace from the device
lumo-notes
A pocket voice recorder with a puppy in it: notes and reminders by voice, transcribed by Whisper on a laptop in the same room, nothing leaving the house.
- Fifteen threads on one core, one owner per device, zero-copy audio
- A kernel-level tracer that animates buffers filling and threads taking turns
Toolbox
What I reach for
- Firmware
- C and C++ on ARM Cortex-M; Zephyr, FreeRTOS and bare metal; peripheral drivers, ISRs, DMA, ADC/DAC, sensor interfaces, state machines, low-power design, board bring-up
- Embedded Linux
- Debian, Docker, systemd, udev, Node-RED, SQLite, Python, Bash, JavaScript, POSIX; golden images, provisioning, update and rollback
- Connectivity
- BLE, LoRaWAN, cellular/LTE, Wi-Fi; MQTT/Sparkplug B, HTTP/HTTPS, TCP/IP; Modbus TCP/RTU, EtherNet/IP, CAN, USB, RS-232/485; 900 MHz radio networks
- Reliability
- Self-healing services, local-first buffering, atomic state, watchdogs, retry logic, health telemetry, pattern-based alerting, remote diagnostics
- Lab & test
- Oscilloscopes, logic and spectrum analysers, DMMs, JTAG/SWD, Wireshark, SDR; schematic review, PCB and assembly verification; manufacturing and calibration test automation; FCC compliance testing
- Process
- Functional safety (IEC 61508 parts 2 and 3) validation and documentation; component qualification; vendor and contractor coordination
Contact
Let's talk about your device
Based in the San Francisco Bay Area. Email is best: [email protected]. I'm also on LinkedIn and GitHub.