Corwin W. Marsh

Software Architect.Agentic Engineer.Dad.

Corwin's profile
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A little about me:

Hi! I'm Corwin. Welcome to my personal site!

I work at Slalom in Seattle as a Senior Architect Software Engineer.

Greater Seattle Area
Since 2014

Technologies I love

I am a fullstack developer with passion for all things frontend.

Here are a few of the technologies I work with and love.

Currently learning

One of the things I love the most about software engineering is that there is always something new to learn.

Feel free to check out my links below to get to know me better.

Featured projects

A few of the developer tools and experiments I've been building.

VS Code extension

oil.code

A VS Code extension inspired by oil.nvim that lets you edit your filesystem like a normal file so common file operations feel fast and keyboard friendly.

  • Built for developers who want an oil.nvim-style workflow without leaving VS Code.
  • Supports create, move, rename, delete, preview, and directory navigation directly from the editor.
TypeScriptVS Code APIVim workflows
MarketplaceGitHub

CLI developer tool

Arashi

A Git worktree manager for meta-repositories that helps keep related repos aligned while working across a shared feature branch and workspace.

  • Designed for multi-repo development and spec-driven workflows.
  • Includes commands for creating, switching, syncing, and setting up coordinated worktrees.
TypeScriptNode.jsGitCLI UX
DocsMarketplacenpmGitHub

tmux integration

coding-agents-tmux

A tmux plugin and CLI for tracking, monitoring, and jumping between terminal coding-agent sessions, with support for busy, idle, and waiting states.

  • Makes it easier to manage multiple agent sessions from a single tmux workflow.
  • Supports pi, opencode, and codex session discovery, switching, popups, and status summaries.
TypeScripttmuxTerminal toolingAgent UX
GitHub

pi ecosystem

pi-extensions

A collection of installable pi extensions that explores small but useful workflow improvements for the pi coding agent experience.

  • Includes packages for asking user questions, copying code blocks, interactive review, and Vim-style quit commands.
  • A place for experimenting with pragmatic extensions that make pi more ergonomic day to day.
TypeScriptpiExtensionsDeveloper experience
GitHubpi.dev

My experience:

A snapshot of the roles that shaped how I build products, lead teams, and think about developer experience.

Current role

Sr. Software Architect

Slalom

Aug 2015 - Present

Partner with clients to turn ambiguous requirements into production-ready software, with a focus on frontend architecture, maintainability, and confident delivery.

Selected impact

  • Led classes and coaching sessions that helped engineers adopt AI tools and workflows, including context engineering, agentic development, and spec-driven development.
  • Led delivery across web, mobile, and serverless projects for clients in multiple industries.
  • Architected React design system foundations for a program with more than 100 team members.
  • Built shared OAuth2 login experiences and client libraries used across multiple applications.
  • Implemented a React Single-Spa microfrontend for administration workflows spanning multiple product teams.

Previous roles

Jr. Software Engineer

Intellicheck Mobilisa

Jul 2014 - Aug 2015

Contributed to identity verification products across internal tools, web applications, backend services, and mobile integrations.

  • Delivered bug fixes and features for internal C# applications.
  • Improved an ASP.NET management tool used in military access control workflows.
  • Strengthened backend services and iOS integrations for identity verification products.

General Manager

Domino's Pizza

Oct 2009 - Jun 2014

Built a foundation in leadership, hiring, and operations while learning how useful software can be for everyday teams.

  • Led teams, hired staff, and managed day-to-day store operations.
  • Built Excel and VBA tools for food ordering and staffing that reduced waste and improved profitability.
  • Shared those tools across the region, helping spark my transition into software engineering.

Connect with me

Want to talk software, developer tools, or AI-assisted workflows? I’m easiest to find on LinkedIn or Bluesky.

Find me online

I’m always up for a good conversation about building useful things.