Portfolio
Work
Work in open source, developer platforms, and the teams behind them.
Python Watchdog Creator
- Open source
- Original author of Watchdog — 100M+ downloads/month, 7,300+ GitHub stars
- Used by
- Google's Agent Development Kit & Dart SDK, Apple's FoundationDB, the AWS SAM CLI, Streamlit, Apache Superset, Home Assistant, and Hugging Face — plus US national labs and agencies (NASA JPL, ORNL, CISA)
What I lead
- Now
- Engineering manager — 5 parallel teams across 6 countries at GlobalLogic consulting for Google
- Recently
- Founding GlobalLogic engineering manager and technical architect for Google's open-source Gen AI SDK, Firebase Genkit; shipped Genkit Python v0.5.0 (Feb 2026)
Impact. I lead 5 parallel engineering teams across 6 countries at GlobalLogic — about 25+ engineers today, scaling toward 45+ as additional projects ramp up. The work spans Google Search, Looker, Firebase, and gRPC; the day-to-day is the usual blend of hiring, technical direction, performance reviews, and trying to build the conditions where good engineers do their best work.
Until March 2026 I led teams for Firebase Genkit, including the founding architectural team for Genkit Python, and Dotprompt — Google's open-source generative-AI SDK and its prompt-as-code companion. Shipping Genkit Python v0.5.0 in February 2026, hiring across four countries through December and January, and then rolling off the team cleanly was among the most satisfying periods of my career.
The source-linked Genkit Python and Dotprompt record separates the implementations, packages, registry signals, public-source users, and contribution history behind that work.
What I've made
The thing I'm best known for is Watchdog — a cross-platform filesystem-monitoring library for Python that I started in 2010 as a side project at a previous job. It has aged improbably well: today it sees 100M+ downloads a month and is a quiet dependency of Google's Agent Development Kit and Dart SDK, Apple's FoundationDB, the AWS SAM CLI, Streamlit, Apache Superset, Home Assistant, and Hugging Face's dataset tooling — and a long tail of scientific and infrastructure software at NIST and ORNL, and beyond. I no longer maintain it day-to-day — it's in good community stewardship — but I'm proud of it the way you can only be proud of something you launched into the world and watched flourish without you. In July 2026 I started sending patches again: supply-chain hardening for the release pipeline, pinning its GitHub Actions to commit SHAs and restricting the workflow token to read-only. Contributing, not reclaiming. I keep a source-linked record of where it runs — across government agencies, national laboratories, operating systems, and industry.
Watchdog is maintained today by Mickaël Schoentgen, who has stewarded the project since 2018 and has cut every release since. I'm grateful it landed in such careful hands — my patches go through his review like anyone else's.
Watchdog is the best-known, but it's one point on a longer line — a steady stream of open-source work and some art, most recent first, running back several decades:
- Hybrid Content Security Policy Enforcement for a Web-Based Application — sole inventor named on Google's published U.S. patent application for a Web security architecture that combines build-time Content Security Policy hashes and Subresource Integrity with per-request nonces for dynamic markup (US 2026/0197352 A1; assigned to Google LLC; patent pending).
- Firebase Genkit — Google's open-source Gen AI framework, used in production. I founded and led its Python SDK and contributed across the project (~380 commits).
- Dotprompt — I wrote the TypeScript (refactored and heavily tested), Go, Java, Rust, Python, and Dart implementations of Dotprompt, Google's prompt-as-code format — including a full Handlebars engine for Dart, which the language lacked — and the Bazel rules that build them (rules_dart, rules_flutter, rules_vitest).
- handlebarrz — a Rust-backed Handlebars engine for Python, shipped as cross-platform wheels (Alpine, arm64, x86-64). Python's usual library, pybars3, is LGPL — unusable in an Apache-2.0 project — so I wrote a clean-licensed replacement, with a Rust core for speed.
- addlicense — added Buck2 build-file support to Google's source-license header tool.
- rules_jvm_external — a fix to detect the Java version correctly in Bazel's JVM-dependency ruleset.
- Looker visualizations — for Google Looker's open-source visualization marketplace I added the testing, CI, and code-quality scaffolding — Jest unit tests, release workflows, input sanitization — across seven viz repos, and review pull requests across twenty.
- Bazel — a credited contributor to the build system itself, named in the release notes from 3.5 (2020) through 7.0 (2023).
- googletest — fixed FreeBSD linker errors in Google's C++ testing framework.
- abseil — a FreeBSD portability fix (the
ElfWmacro) in Google's C++ common libraries. - bazel-skylib — a more portable shebang in Bazel's standard Starlark library.
- grpc — an re2 upgrade to unbreak the build on gcc-11, in Google's RPC framework.
- flatbuffers — fixed linker errors on FreeBSD/OpenBSD in Google's serialization library.
- rules_foreign_cc — added a FreeBSD toolchain to Bazel's foreign-build-systems ruleset.
- utest.h — a run of cross-platform fixes (FreeBSD, DragonFly, Solaris, Haiku, MSYS2 / MinGW) to the C/C++ unit-testing header.
- cctz — exported the test suite to downstream Bazel workspaces in Google's civil-time library.
- double-conversion — fixed the Bazel build for downstream projects in Google's float-to-string library.
- rules_rust — updated rustfmt in Bazel's Rust ruleset.
- google/benchmark — a FreeBSD/OpenBSD linker fix in Google's microbenchmark library.
- A patch to Vim — I taught it to recognize Bazel's
*.BUILDand*.bazelfiles, and Bram Moolenaar applied it himself (#6836). I still use his editor almost every day. - libsass — a fix to libsass, the C/C++ implementation of Sass.
- Cython — a listed contributor to Cython, the optimising Python-to-C compiler.
- Emacs themes and patches — I adapted and packaged Marcus Crafter's TextMate-inspired Twilight theme for the Marmalade archive; Crafter merged the work upstream, and the published descendant still preserves the
Adapted-By: Yesudeep Mangalapillycredit. The same run included clojurescript-mode support in auto-complete, fixes to iedit and emacs-powerline, and packaging the GitHub color theme for Marmalade. - webapp2 — a spot in the AUTHORS of webapp2, the framework that shipped inside Google App Engine — part of a run of App Engine work, including a DecimalProperty for tipfy and packaging fixes for webapp-improved.
- Watchdog — the cross-platform filesystem-monitoring library I'm best known for, written in 2010, maintained as primary author through 2016, and contributed to again since 2026: 100M+ downloads a month, packaged into most Linux distributions, and depended on from national labs and government agencies to Google's Dart SDK and AWS's SAM CLI. Where it runs →
- A faster
trim()— an essay on a 50–60× fasterString.prototype.trim, adopted into early JavaScript frameworks. - A Christmas patch — somewhere in a 2005 changelog, a maintainer still thanks me for it.
- WebView XP — the first thing I ever open-sourced: a Windows XP–style Explorer pane for Windows 98 and 2000, released under a teenage alias, Art Sands — followed soon by a community wikibook on x86 assembly (archived) I proposed.
- Vikas Colourful Rhymes — my very first credit of all: a child singer on a cassette of nursery rhymes, the earliest thing I ever shipped to an audience. The music was credited to Josfi — my father — a credit Amazon's listing still carries (archived), decades after the cassette left the shelves.
For the full professional record, see the CV.