Keir Mierle

Keir Mierle is a software engineer whose work spans computer vision, speech recognition and embedded systems. He coauthored a 2007 operating-systems paper and Astrometry.net, then helped build Ceres Solver and libmv. With Thad Hughes, he coauthored a 2013 recurrent neural network for voice activity detection, and Ceres Solver received the 2023 Mark Everingham Prize. At Google, he led the Pigweed team and co-announced its SDK, whose components have shipped in millions of devices. As of October 2026, he contributes code to Pigweed.

Now at: Google

Timeline

2007

JIT instrumentation paper

In 2007, he coauthors a EuroSys paper with Marek Olszewski, Adam Czajkowski and Angela Demke Brown on dynamically instrumenting operating systems.
2009

Astrometry.net for sky images

In 2009, he coauthors Astrometry.net, a system that takes an astronomical image and returns its pointing, scale and orientation without a first guess.
2010–May 2012

Ceres Solver at Google

In early 2010, Ceres Solver grows from Google's need for general least-squares solving; Sameer Agarwal and Frederik Schaffalitzky start the library, and Mierle takes Schaffalitzky's place after he leaves Google. In May 2012, Mierle and Agarwal, both Geo software engineers at Google, release Ceres as a portable, open-source C++ library for large nonlinear least-squares problems, from fitting statistical curves to building 3D models from photographs. Google uses it to estimate the pose of Street View cars, aircraft and satellites and to build 3D models for PhotoTours.
2011

Libmv in Blender tracking

In 2011, he is libmv's primary developer; its structure-from-motion algorithm drives Blender's motion tracking. The method relies on rigid motion, so non-deforming cars, trucks, buildings and airplanes track well.
2013

A recurrent model for voice detection

With Thad Hughes, he presents a recurrent neural network for voice activity detection at ICASSP in 2013. It uses one tenth the parameters of a Gaussian mixture baseline, cuts false alarms by 26%, reduces speech-recognition computation time by 17% and lowers word error rate by 1%.
2023

The Mark Everingham Prize

At ICCV 2023, Keir Mierle and Sameer Agarwal receive the Mark Everingham Prize for Ceres Solver.
As of October 2026

Contributing to Pigweed

In March 2020, he and Mohammed Habibulla announce Pigweed, Google's open-source libraries for 32-bit microcontrollers; he leads the team and teaches its Hackaday Remoticon workshop in 2020. In August 2024, as a Google software engineer, he co-announces the first Pigweed SDK preview with native Bazel and Raspberry Pi Pico 2 support; its components have shipped in millions of devices, including Pixel devices, Nest thermostats and DeepMind robots. As of October 2026, he contributes code to Pigweed; in September 2026, he adds pw_ghish, a CLI that wraps Gerrit and LUCI Buildbucket workflows and includes AI integration, and in October 2026 he updates cancellation handling in pw_async2.