Work Experience

Senior Programming Language Engineer, Chapel

Hewlett Packard Enterprise | Summer 2022 - Present

Implemented compile-time reflection, parallel iterators, and trait-like interfaces in Chapel's C++-based compiler.
Led development of Python bindings for compiler, accelerating development of a linter and a language server by over 10x.
Optimized scope resolution and type checking compiler passes, improving performance by 30% and 60% respectively.
Designed a type-safe error reporting API, improving developer experience and enabling 100+ custom error messages.
Supported community growth by designing, launching, and authoring articles for the Chapel language technical blog.
Laid groundwork for compatibility with leading-edge supercomputers by implementing initial AMD GPU programming support using Clang and ROCm tooling.

Research and Teaching Assistant, Programming Language Theory

Oregon State University, Corvallis, OR | Spring 2018 - Summer 2022

Formalized denotational and operational semantics of new explanation-oriented programming languages.
Developed tooling in Haskell to interpret, verify, generate, and debug programming languages.
Contributed to research papers published to the GPCE and VL/HCC.
Proctored quizzes and exams for over 200 students.
Aided students in implementing a final project in the form of a custom programming language.
Suggested and organized independent review sessions attended by over 70 students, with 50% attendance growth between sessions.

Front-End Intern, Hydrogen

Element.io | June 2021 - September 2021

Spearheaded migration of codebase to TypeScript, improving documentation and discovering hidden bugs.
Leveraged advanced type system features to precisely specify nontrivial program properties.
Developed a mocking system to help specify and test corner cases in a distributed communication system.
Independently implemented user-facing features including offline-first replies and sanitized HTML rendering.
Engaged in open-source development, interacting with community to respond to bug reports and feature requests.

Projects

agda-spa

— Framework for formally-verified lattice-based program analysis in Agda, explained in-depth in a series of posts.

bloglang

— Compiler for a functional, lazily evaluated language using C++ and LLVM, explained in-depth on personal blog.

maypop

— Dependently typed functional programming language capable of formal proofs, written in Haskell.

matrix-highlight

— TypeScript-based browser extension for collaborative web annotation based on the Matrix protocol.

Publications

Divya Bajaj, Martin Erwig, Daniel Fedorin: A Visual Notation for Succinct Program Traces (journal paper), COLA 2023
Divya Bajaj, Martin Erwig, Daniel Fedorin, Kai Gay: Adaptable Traces for Program Explanations, APLAS 2021
Divya Bajaj, Martin Erwig, Daniel Fedorin, Kai Gay: A Visual Notation for Succinct Program Traces, VL/HCC 2021
Jácome Cunha, Mihai Dan, Martin Erwig, Daniel Fedorin, Alex Grejuc: Explaining spreadsheets with spreadsheets (short paper).
GPCE 2018: 161-167

Education

Master of Science, Oregon State University, Computer Science - Completed June 2022 • 4.0 GPA

Thesis: Guided Translation of Algorithmic Notation into Functional Programs

Bachelor of Science, Oregon State University, Major: Computer Science | Minor: Mathematics - Completed June 2020 • 4.0 GPA

Additional Experience

Technical Writer

Independent | Spring 2015 - Present

Designed and published website currently live at danilafe.com, peaking at 27k daily unique visitors.
Authored blog posts on topics spanning data structures, web development, programming languages, and compilers.
Formalized and described solutions to select Advent of Code problems using the Coq proof assistant.
Created 14-part series on compiler development, walking readers through lexing, parsing, compilation using LLVM, garbage collection, and polymorphic type checking.