Technical architecture and IoT product development revolutionizing the future of food waste.

Tech Stack

  • Elixir
  • Sanity
  • React Native
  • Typescript
  • Elixir Phoenix
  • AWS IoT Core


Mill had ambitions for producing a smart food waste bin that would reduce consumers’ greenhouse gas emissions. Sanctuary Computer worked with Mill to bring it all online.

Project Overview

  1. 1.

    Technical Blueprinting

    We partnered with Mill’s firmware development team and product designers to define a technical plan that would support their IoT-connected bin, mobile app, and web experiences.

  2. 2.

    App Development

    We brought the plan to life, tackling Bluetooth pairing and account creation, Food GroundsTM processing, and content management. This work culminated in the release of the Mill: Kitchen Bin Companion app (Android, iOS) in April 2023.

  3. 3.

    Embedded Teaming

    Sanctuary Computer currently serves as Mill’s embedded product team, building software as a single team with Mill’s in-house product managers, designers, firmware developers, and QA team to continually roll out features.

A genuine partner in defining technical architecture and product roadmap.

The Mill kitchen bin is an ingenious device that works to convert wasted household food into Food Grounds™️ for chickens.

We began working with the Mill team when their bin was in prototype, working hand-in-hand from foundation to launch.

We were able to meet the Mill team where they were at, as critical partners in shaping and defining these highly specific technical needs.

We delivered an in-depth technical blueprint, providing a plan that was thorough enough for us to be confident we’d achieve our goals on-time and on-budget — without being overly prescriptive, since the plan was destined to change as we learned more about the product alongside Mill.

We advised Mill on which technologies, frameworks, and development practices would make their e-commerce website, user intake flow and Android and iOS apps a reality.

An accessible interface for a mighty little machine.

The beauty of the Mill product is its power to fit into consumers’ lives as seamlessly and elegantly as a Sonos speaker or Nest thermostat — while drastically curbing their environmental impact.

Our partnership with Mill was based on the mutual understanding that this tool was only as good as the consumer touchpoint it interacted with. If we wanted to help users make a positive environmental impact, the first step was building an app they would enjoy using.

Reliable Firmware Pairing

Anyone who has used a bluetooth speaker before knows how finicky and frustrating pairing can be. Our first challenge was making the Mill kitchen bin onboarding experience the exact opposite: reliable and easy. We leveraged industry standard Espressif toolkits, expanding on them when needed to account for behavior that was particular to the Mill Kitchen bin’s firmware.

A modern app experience

The app’s core features are to indicate the bin’s processing cycle with live updates, to send push notifications if the bin requires attention (in the case of a jam or other error), schedule bin cycles, let users know what can and can’t go in the bin, and ship their Food Grounds™️ so that they can be used on farms.

Once a bin is paired to a user’s phone, the app receives constant updates about the bin’s status. We reached for Elixir here since Erlang's VM-backed concurrency model was just what we needed to scale safely. For the mobile app, we opted for React Native and Typescript. (Can you tell we like type safety?!)

A convenient customer service

Scheduling Food Grounds pickup is key to Mill’s business model and to their role in the sustainable food cycle. We collaborated with Mill’s designers to build a simple Food Grounds™️ pickup experience into the app’s core capabilities.

Our system also detects when a user’s bin is full and prompts them to empty their bin and schedule a pickup by way of a push notification, which is originally triggered by a handy AWS IoT rule.

Sanctuary Computer serves as Mill’s embedded product team.

At Sanctuary, we believe that managing things is a maker skill. That means that our developers don’t just write code — we also self-organize, setting our own deadlines and goals and communicating directly with the Mill team.

We keep Mill’s needs top-of-mind whenever our hands are at the keyboard so that our code (and the amount of time we spend on our code…) is attuned to the core business need it is aiming to solve. One team, operating in lockstep, toward product nirvana.

The Mill Kitchen Bin reduces an estimated half-ton of consumers’ greenhouse gas emissions per year. We’re so proud to be a part of such a meaningful and interesting journey!