Matthew Leffler
Principal Software Engineer at Types & Symbols
Eureka, Montana, United States
Summary
🤩
Rockstar🎓
Top SchoolMatthew Leffler is a Principal Software Engineer with 15 years of hands-on experience building pragmatic, well-crafted web applications and developer tools from Montana. He blends front-end expertise—demonstrated by UI work on the Alloy Editor and cross-browser fixes—with back-end contributions to NestJS GraphQL and extensive TypeScript typing work in DefinitelyTyped. Matthew favors practical perfection: shipping solid, maintainable code while improving developer ergonomics like schema sorting and accurate library types. A creative polymath off-hours (photographer and pianist), he brings a meticulous, user-focused perspective to both UI interactions and API design.
15 years of coding experience
18 years of employment as a software developer
High School, Web Programming, High School, Web Programming at Leffler Homeschool
English
Stackoverflow
1,406reputation
94kreached
39answers
2questions
Github Skills (35)
javascript10
typescript10
typescript-definitions10
ui-design10
type-definition10
wpgraphql10
nestjs10
uid10
dts10
front-end-development10
wordpress-graphql10
typescript-types10
graphql10
nodejs10
typescripts10
Programming languages (16)
Github contributions (5)
nestjs/graphql
Jun 2020 - Aug 2022
GraphQL (TypeScript) module for Nest framework (node.js) 🍷
Role in this project:
Back-end Developer
Back-end DeveloperContributions:2 reviews, 7 commits, 10 PRs in 2 years 2 months
Contributions summary:Matthew primarily contributed to the NestJS GraphQL module, enhancing its functionality and addressing code issues. Their work involved adding features such as schema sorting and applying transformations to the auto-generated schema file. Additionally, the user fixed typos and made adjustments to enum definitions, including the deprecation of enum values, improving the code's overall correctness. These changes focused on improving the schema generation and handling of GraphQL types.
nestjsapollographqltypeormnode-jsjavascript
DefinitelyTyped/DefinitelyTyped
Jan 2018 - Mar 2022
The repository for high quality TypeScript type definitions.
Role in this project:Full-stack Developer
Full-stack DeveloperContributions:2 reviews, 7 commits, 7 PRs in 4 years 2 months
Contributions summary:Matthew primarily contributed to type definitions for various libraries within the `definitelytyped` repository. Their work included updating and expanding type definitions for the Vimeo and ImageKit libraries, ensuring compatibility with the latest versions. They also integrated new features like picture-in-picture and save APIs in react-native-video, and updated the video.js types. These contributions demonstrate a focus on maintaining accurate and comprehensive TypeScript type definitions for external libraries.
typescript-definitionstype-definitionshigh-qualitydtsdefinitions
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