Michael Dalessio

github.com/flavorjones mike.daless.io mike.dalessio@gmail.com NYC/NJ

I write code for a living, but I also do it for fun. I've had success as an executive, a manager, and a technical lead. I encourage software development practices which emphasize early and continuous delivery of valuable software. I try to always respect the humanity of the people who must collaborate well in order to build excellent products.

TL;DR

Technology Skills

Ruby and Rails.: I love Ruby, though I'm comfortable in many other languages. In Ruby, I have experience writing native extensions in C, Java, and FFI, and am familiar with the garbage collector. At Shopify, I supported one of the largest web sites anywhere and have experience with performance analysis.
Distributed systems.: After working on Cloud Foundry for a few years, I know some things about developing, operating, and maintaining a distributed computing platform, and about the interesting emergent behavior you see when the platform is put under stress.
C, C++, FORTRAN.: I've designed and implemented SDKs and have experience writing portable code for platforms old and new. Yes, I've got deep knowledge of FORTRAN, having integrated it with C and C++ at the source level and at linktime. No, I don't expect this to ever be useful again.
Other languages.: I've written Golang, Java, Lisp, Clojure, Scala, Rust, Perl, and a handful of other languages in addition to what's listed above; though I wouldn't claim to be an expert in any of them. Oh, but I am a bash wizard.
XML and HTML.: I've been maintaining the Nokogiri library for over a decade, so I'm intimately familiar with the XML, XPath, HTML4, and HTML5 specs. I also am a co-maintainer of the libgumbo HTML5 parser used by Nokogiri.
System-level programming.: I've got experience with threaded and evented processing models. I've done network programming on both *nix and Windows using TCP and UDP. I've built a fault-tolerant load balancer and implemented job scheduling algorithms.
Figuring It Out.: I can read man pages. I know what an RFC is. I like reading other people's code.

Organizational and Human Skills

Team Building.: I've had success hiring and managing strong, inclusive development teams, and improving existing teams.
Framework Design.: I've designed and built application frameworks to deliver complex functionality to domain-expert developers. Notably, I designed and built the SDK used by Bloomberg to build Launchpad.
Mentoring.: I'm able to mentor developers in technology and design, both in an informal office setting and in formal training classes. I'm also an experienced technical trainer, having run many large "developer boot camps".
Client management.: I've got years of experience working with clients of all sizes in a variety of verticals. I know that everything works better when people trust and respect each other.
Financial and Energy Markets.: I have experience building trading systems for equity and fixed income financial markets, and for energy markets. I'm also comfortable with bond math and the FI derivative market.
Mad Communication Skillz.: Me talk good. Me also write good. Me so funny.

Professional Experience

Software Developer @ 37signals (Sept 2024 — present)

Member of the Security, Infrastructure, and Performance ("SIP") team, working on the infrastructure that powers Basecamp, HEY, ONCE, and more.

Director of Engineering @ Shopify (June 2020 — March 2024)

Led the Ruby and Rails Infrastructure team, dedicated to making Ruby and Rails 100-year tools. Part of the Developer Acceleration team.

VP of Engineering @ VMware (via acquisition, Dec 2019 — June 2020)

Led the Tanzu "Modern Application" R&D team of 400+ engineers worldwide on Cloud Foundry and related Kubernetes and Data Services products.

Pivotal (2012 — 2019)

VP, Engineering @ Pivotal Cloud Foundry (Oct 2016 — Dec 2019)
Engineering Director @ Pivotal Cloud Foundry (July 2014 — Sept 2016)

Wore many hats to help the Pivotal Cloud Foundry engineering organization scale out to 80+ teams in eight cities across eight timezones.
For the CF Foundation, led two OSS Project Management Committees: Buildpacks and Developer Tools.

Director @ Pivotal Labs NYC (Sept 2012 — July 2014)

As the business owner of the NYC consulting practice for Pivotal Labs, was responsible for all aspects of revenue and headcount.

Director of Technology @ Benchmark Solutions (Feb 2010 — Aug 2012)

I was the manager and technical lead for the frontend team (web and native Windows client), the realtime data infrastructure team, and the reference data team.

Pivotal Labs (2008 — 2010)

Director, NYC consulting business. (Sept 2009 — Feb 2010)

As the business owner of the NYC consulting practice for Pivotal Labs, was responsible for all aspects of revenue and headcount.

Agile Software Developer. (Nov 2008 — Sept 2009)

Consulted with multiple clients to implement web applications built with Rails and Javascript.

Founder @ Pharos Enterprise Intelligence (Jan 2008 — Dec 2018)

Architect and lead developer for a turn-key SaaS Energy Management System which helps North American power plant operators run their business and bid their units into the energy markets.

Director of Application Development @ USPOWERGEN (May 2006 — Dec 2007)

System architect and lead developer for an in-house Energy Management System.
Director of technology across multiple power plants.

Head of Software Development @ ASPEED Software (Aug 2004 — Apr 2006)

Managed a team of developers building SDKs for parallel computing on large clusters.
Assisted clients in parallelizing applications (Professional Services). Lead developer on parallel-computing SDK.

Infrastructure Applications Lead @ Moneyline Telerate (Nov 2003 — Aug 2004)

Managed a team porting applications to a new pub/sub API as the last phase of a ticker plant rollout.
Managed a team of offshore developers building an internal application for browsing ticker plant data.
Implemented a high-performance UDP feed to integrate third-party data vendors.

Bloomberg, L.P. (1995 — 2003)

Architect and Project Lead for Bloomberg Launchpad @ (2001 — 2003)

Managed a high-performing expert team.
Designed, built, and led development on Bloomberg Launchpad, the next-gen Bloomberg UI, and implemented core services for pub/sub and instant messaging.

Trading Systems Engineer (1995 — 2001)

Designed and built the Trading Systems Desktop ("TW") using the new Bloomberg UI (Win32 controls).
Built and maintained a set of customer-facing TCP/IP feeds.
Coordinated and taught the Bloomberg "boot camp" developer training classes.
Wrangled a huge time-series dataset.

Volunteer Work

Member of the Ruby Central OSS Committee (2023 — present)

This committee meets periodically to advise and direct the OSS team funded by Ruby Central.

Member of the Ruby on Rails security team and triage team (2023 — present)

I'm a contributor to Rails, and the de facto owner of Rails's HTML sanitization stack, which led to my joining the security team. As a member of the security team, respond as needed to vulnerability reports. As a member of the triage team, make initial reviews and responses to issues and pull requests.

Co-organizer of GORUCO (2015 — 2018)

GORUCO was the premier NYC regional Ruby conference, convening annually from 2007 — 2018.

Startup Advisor

Prospective (May 2024 — current)

Advising open-source startup Prospective on delivering fast data visualization in the browser.

Gitwallet (Feb 2024 — current)

Advising startup focused on helping open-source maintainers monetize their expertise.

True Diversity (Jan 2021 — Oct 2021)

Advising startup focused on improving diversity and equity in the tech industry.

Open Source Experience

Maintainer of nokogiri

Nokogiri is currently the most popular XML/HTML parsing library for Ruby developers. It supports CSS and XPath querying, has push and pull SAX parsers, validates schemas, performs XSLT transformations, and has a very simple and usable API. It's implemented in Ruby with native extensions in C and Java.

Maintainer of loofah, loofah-activerecord, and rails-html-sanitizer

Loofah underlies the default HTML sanitizer in Rails, which can be used to prevent cross-site scripting (XSS) attacks. It provides a variety of methods to clean or remove unsafe HTML, and delivers ActiveRecord plugins for Rails applications.

Rails HTML Sanitizer is the default library for sanitizing HTML fragments in Rails applications.

Maintainer of sqlite3 Ruby gem

The sqlite3 ruby gem is the original and most widely-used Ruby database adapter for SQLite.

I also maintain the the sqlean Ruby gem which wraps the sqlean sqlite extensions with Ruby accessors.

Mechanize is a Ruby library used for automating website interaction and screen-scraping. It fully supports browser history and cookies, and allows easy authentication and form submission. The http-cookie project delivers standards-compliant cookie handling.

Maintainer of rake-compiler-dock, mini_portile, and ruby-c-extensions-explained

The rake-compiler-dock project delivers OCI images to help maintainers build precompiled native gems. It's the Ruby analog for Python's pypa/manylinux project for building Wheels.

The mini_portile project helps gem maintainers integrate native extensions with autoconf projects.

Finally, the Ruby C Extensions Explained is a project that demonstrates and documents a variety of ways to package and precompile native C code in a Ruby gem, complete with CI pipelines and two conference talks explaining the approaches.

Maintainer of tailwindcss-rails and tailwindcss-ruby

tailwindcss-ruby packages tailwindcss, and tailwindcss-rails provides tight integration with Rails.

Selected Smaller Projects and Contributions

I've made contributions to many other Ruby-related projects, including Rails, the Ruby language and its Prism parser, rdoc, the Truffleruby interpreter, Mastodon, Active Hash, racc, rexical, chromedriver-helper rake-compiler, sanitize, crass, grpc, ruby-magic, ruby-ffi, hoe-debugging, hoe-gemspec, hoe-bundler, and concurrent-ruby.

Outside of Ruby, I've made contributions to libxml2, git, valgrind, DOMPurify, and rofi.

Undergraduate Experience

NASA Space Telescope Science Institute (1993 — 1995)

Research assistant to Dr. Rex Saffer

Studied Subdwarf B stars and their rotational velocities.

Rowland Department of Physics @ The Johns Hopkins University

Research assistant to Dr. Doyle T. Hall (1993 — 1995)

Studied Jupiter and its moons, primarily through analysis of Voyager and IUE data.