Open-source farm stack

An ESP32 costs a few dollars, has WiFi and Bluetooth built in, runs from a USB cable, and reads sensors and drives relays through general-purpose I/O pins. It is the workhorse of the small-farm sensor network — wired to a soil-moisture probe, a temperature sensor, a relay controlling an irrigation valve. The first dollar of the open-source farm stack is here.

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ESPHome is YAML-driven firmware for ESP32 and ESP8266 devices. You write a configuration file describing what is wired to what, ESPHome compiles the firmware, the device flashes itself and reports to your local network. No cloud. No vendor lock-in. The same hardware can run anything as the configuration evolves.

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Tasmota is the firmware you flash onto cheap consumer smart-home devices — Sonoff switches, smart plugs, sensor pucks — to replace the manufacturer's cloud-dependent firmware with locally-controllable software. The same supply chain that makes consumer IoT cheap becomes available for the farm without surrendering data and control to the vendor.

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MQTT is the lightweight publish-subscribe protocol that ties the stack together. Sensors publish readings to topics. Controllers subscribe to topics. A local MQTT broker (Mosquitto, EMQX) running on a Raspberry Pi is the backplane of the farm network. Simple, well-documented, almost universally supported.

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Home Assistant runs on a Raspberry Pi or any Linux box. It collects readings from every MQTT-publishing device, runs automations, presents dashboards, sends notifications, and integrates with hundreds of other systems. For a farm, it is the operations layer — *if soil moisture is below X then run drip valve for Y minutes*. A free, local, unbreakable alternative to the proprietary controllers commercial systems sell for thousands of dollars.

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Where Home Assistant is general-purpose, Mycodo is purpose-built for environmental control of growing spaces — mushroom rooms, fermentation chambers, hydroponics, propagation tents, greenhouses. PID loops, conditional logic, recipe-style stage progression, full sensor and output libraries. The dominant open-source choice for indoor cultivation.

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FarmBot is a CNC-style gantry robot mounted over a raised bed that plants, waters, weeds, and monitors crops with millimeter precision. Open hardware, MIT-licensed software, fully documented for self-build. The principal small-scale agricultural robotics platform aligned in scale and ethos with regenerative practice.

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FarmOS is the management software — plantings, harvests, animal events, observations, soil tests, equipment maintenance, geospatial maps. Self-hosted Drupal application; the data lives on infrastructure the farmer controls. The records layer of the open-source stack, designed to keep the farmer's data the farmer's.

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Farm Hack is the peer-to-peer community where farmers post and share tool designs under open-source licenses. The platform's principal artifact is a *tool wiki* with hundreds of entries — manual, mechanical, electronic — documented well enough to build, modify, and repair. The North American node of the international open-ag-tools community.

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L'Atelier Paysan is the French farmer-led cooperative that designs, documents, and trains farmers to build their own tools — bicycle-derived cultivators, manual transplanters, modified two-wheel tractors. The European node, with build-it-yourself weekend workshops and a cooperative business form that preserves the commons rather than capturing it.

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The Open Ag Tech Collective (GOAT) is where these projects coordinate — annual conferences, shared standards, cross-project mutual support. The reason the components compose: not a single organization, but a community-of-communities maintaining the open-source agricultural commons across institutional and national boundaries.