Contractor: Senior Build System Engineer

The Open Home Foundation is looking for a Senior Build System Engineer to join our Ecosystem department on a contract basis for a specific, high-impact project for ESPHome.

This department is responsible for the development of several projects under the Open Home Foundation umbrella, including ESPHome.

ESPHome currently relies on PlatformIO which acts as an abstraction layer between ESPHome and the underlying vendor SDKs (like ESP-IDF). For ESP(32) projects using the ESP-IDF framework, this abstraction now adds complexity without clear benefit. The ESP-IDF already has a mature CMake-based build system that ESPHome could invoke directly.

The goal of this project is to phase out our dependency on PlatformIO.

By eliminating PlatformIO from the ESP-IDF path, we remove a third-party dependency that must be maintained and versioned. This simplifies the toolchain and reduces potential points of failure. Crucially, it enables faster issue resolution. Currently, when upstream dependencies break, ESPHome is often blocked waiting for PlatformIO to release a fix. With direct ESP-IDF integration, we can diagnose and ship fixes within hours, rather than weeks.

This role will involve significant architectural work involving both the large C++ core codebase and the Python code generation component.

What you are going to do

• Lead the architectural design to replace PlatformIO's orchestration role within ESPHome with a native, Python-based solution that interacts directly with vendor SDKs.

• Implement direct integration with native toolchains, specifically focusing on the Espressif IDF (IoT Development Framework) using modern CMake.

• Develop the mechanisms within ESPHome's Python backend for toolchain acquisition, version management, and library dependency handling that PlatformIO previously managed.

• Update ESPHome’s existing Python CLI and dashboard code to seamlessly utilize the new CMake-based build backend.

• Review code from team members regarding build system changes.

• Ensure the new build system reliably produces working binaries across supported platforms and complex configurations.

What you need to have

• Senior experience in architecting and implementing complex software build systems.

• Expert-level knowledge of modern CMake, specifically in cross-compilation environments for embedded systems.

• Strong expertise in Python development, as the glue code orchestrating the build is written in Python.

• Deep understanding of embedded toolchains (compilers, linkers, sysroots) and vendor SDKs, particularly Espressif IDF.

• Experience with Git and GitHub.

• Professional Fluency in English: Excellent written and verbal communication skills in English.

It would be great if you also have

• A passion for smart homes and automation.

• Experience as an ESPHome user.

• Previous experience contributing to, or deeply analyzing the internals of, PlatformIO.

• Experience with C/C++ package management design concepts (e.g., Conan, vcpkg).

The conditions

• This is a project-based contractor position with a clear definition of done: a release of ESPHome that directly uses CMake/ESP-IDF without requiring PlatformIO.

• The Open Home Foundation is a fully remote organization; you can work from anywhere in the world.

• Because we are a fully remote company, there is no fixed schedule. However, for team communication, we try to ensure at least 3 hours of overlap in the workday with the members of our team, who are mostly based in Europe.

• Your point of contact will be our Ecosystem Lead.

• Compensation will be based on an agreed-upon hourly or project rate commensurate with the niche, senior expertise required for this architectural shift.

About us

The Open Home Foundation is a non-profit organization based in Switzerland, with the objective of fighting for the fundamental principles of privacy, choice, and sustainability for smart homes. It does this by supporting the development of open-source projects and open connectivity and communication standards.

A big part of this is Home Assistant, but the Open Home Foundation also owns or collaborates with other projects important to promoting privacy, choice, and sustainability in the smart home, like ESPHome.

The process

• Apply for the project.

• Our team will review your application.

• Initial interview.

• Portfolio review.

• Interview with the team.

• Contract Offer.