An engineer, quietly
building in public.

Statement

I'm twenty. I've been building with microcontrollers since sixteen. The rest is a series of small, deliberate decisions to take the work seriously, and to let the work speak before I do.

Pronouns he / him
Lesley John Jumbo
LJJ / Portrait 2026
No.07

I started building with microcontrollers in 2021. Since then, I've won three hackathons, earned Top Honors in the National Geographic Society Slingshot Challenge out of 2,700+ entries across 96 countries, spoken at TEDx twice, and built Reforest AI; a Climate Tech startup protecting forest-backed carbon assets.

I grew up in Nigeria. The gap between what infrastructure could do and what it actually did, the lights, the meters, the signal, pushed me toward hardware early. I learned to solder before I learned most frameworks, and I still think of software the way I think of firmware: as a thing that has to survive its deployment environment.

My work sits at the intersection of low-level engineering and product thinking. I care about what the system does in the field, not what it demos on a table. That's the throughline, whether I'm laying out a board, shipping a React app, or designing a monitoring pipeline for forests half a continent away.

Outside the work: I read, I write slowly, I spend time in forested places when I can. I believe good engineering is a form of restraint.

In the press.

A Timeline

Five years, in order.

2021 Beginning First microcontroller. Picked up an ESP32 and never really put it down. Early experiments in sensors, motor control, and networked devices.
2022 Competition First hackathon win. Shipped a working hardware prototype inside a 48-hour build window. First taste of scope discipline.
2022 Hardware Air Clicks. Gesture-controlled wearable input device. The project that put the work on the map.
2023 Stage 2× TEDx Speaker: The Future of Robotics + TEDx Countdown. Two TEDx appearances. First on robotics, second on climate action through TEDx Countdown.
2024 Hardware / Product Hi-Wear, WaveFlush, The Vase & RenalScape Pro. Smart footwear (Hi-Wear), hands-free flushing (WaveFlush), a talking plant monitor (The Vase), and a 3D-printed household water tester for Africa (RenalScape Pro).
2024 Venture Founded Reforest AI. Climate tech startup protecting forest-backed carbon assets. Currently in operation with REDD+ pilot partners.
2025 Recognition Nat Geo Slingshot, Top Honors. Selected from 2,700+ entries across 96 countries. $10,000 grant awarded to Reforest AI.
2026 Now Currently operating Reforest AI. Taking selective embedded and software engagements alongside. Writing less, building more.
03 / Onward

Let's work on something together.

Open to embedded systems contracts, software projects, and conversations about climate tech.