Josh Duff

me@JoshDuff.com

I like to work on boring-sounding business software that people use to get their jobs done.

I prefer to work as a product manager+developer, interacting directly with customers and translating business requirements into deliverables.

I've worked for employers with lots of developers that shipped buggy software slowly. I've worked on small teams that shipped great software reliably. I prefer the latter.

I've been working remote since 2013, though I've appreciated working once a week from coffee shops with nearby coworkers at a couple of jobs.

Previous employers

Duff Ventures (contracting) 2025-current

TypeScript, React, Svelte, MySQL

• For a printed circuit board manufacturer: developed a purchasing system to order the parts needed to satisfy a bill of materials from multiple vendors, optimizing for price, lead time, attrition, etc.
• For an arborist: developed an instant estimate system for lead generation

Workshop (internal communications) 2023-2025

TypeScript, Vue, Postgres, Cloudflare Workers

Developed an email editor (think the interface you use to create emails in MailChimp or similar marketing email senders) to replace a third-party whitelabeled editor.

T.Rex Arms (ecommerce, fulfillment, manufacturing in the firearm accessories industry), 2020-2023

TypeScript, Svelte, MySQL, Cloudflare Workers, node.js

Worked primarily on the internal software that coordinated inventory, sales, fulfillment, customer service, manufacturing.

• Developed queue-based task workers to integrate with Quickbooks and other third-parties
• Developed a barcode-scanner interface for warehouse workers to audit stock levels and move inventory. Eyes-free, tolerant to loss of internet or server downtime, all business logic server-side.
• Developed the storefront interface for a holster picker, with every color+pistol+light combination driving manufacturing details in the backend
• Developed a work order system

EquipmentShare (heavy construction equipment industry), 2019-2020

TypeScript, lit-html

Developed the front-end of a payroll administration webapp. My team worked on time-tracking for truck drivers: the truckers used a mobile app to log their time for compliance and payroll purposes.

I built out the front-end webapp used by company administrators. Solved unnecessarily difficult timezone problems with the JS Date API. Published a pretty good date range selector.

Duff Ventures (contracting) 2017-2019

TypeScript, Svelte, node.js

Freelanced for clients in the publishing and customer service industries. Highlights included:

• Building a markdown→Leanpub CI publishing pipeline, including book linting
• Getting screensharing to work for nested iframes in Median Cobrowse

Cake (consumer software), 2016-2017

TypeScript, React, MySQL

With two other developers, added features and fixed bugs to get a node.js/Express/React app (a forum-based social network, now defunct) closer to shipping.

eDataSource (email marketing industry), 2013-2016

Java, AngularJS, MySQL/RDS/Aurora, Hadoop/Apache Pig

• With a team of 3-4 developers:
  • Built and maintained a distributed Java application that processes millions of emails per day, indexing the commercial email campaigns and storing the results in MySQL and ElasticSearch
  • Developed a client-facing AngularJS application used by email marketers to determine the effectiveness of their campaigns and diagnose email deliverability problems
  • Maintained Boxbe, a spam-filtering service used by 1M+ users
• As a single developer/product manager, built the internal admin site that customer account managers used to edit the domain/brand/company taxonomy, and administrate client user accounts

ISoft Data Systems (car parts and heavy truck parts industries), 2005-2013

C++, MFC, MySQL, JavaScript, PHP, node.js

My first "real" dev job. I started part-time as the first dedicated phone-answerer/customer support, started making code changes between calls, then made the jump to full-time development.

• Was the lead developer/product manager for an inventory/point of sale application built with C++/MySQL
• Travelled to customer locations to perform installations and training
• Made a minimal CRM tool for internal support use, using PHP and MySQL
• Worked with partner customers to develop an enterprise application for the heavy truck parts industry
• Made a push-based replication tool for MySQL databases (would not recommend)
• Made an application to query Quickbooks desktop company files directly
• Made a barcode scanner webapp for use on mobile phones with barcode scanners
• Made a front-end framework in JavaScript capable of running in Windows CE's IE6 and Safari Mobile
• Maintained and added to a suite of reports built with Crystal Reports and MySQL queries

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Open source

Larger projects

• spyfallx.com, an implementation of a popular tabletop party game (source)
• abstract-state-router, a framework-agnostic nested state router for web applications
• susdsearch.com, an improved search site for some of my favorite reviewers (source)
• canonreader.com, a Bible reader (source)
• buyadagger.com, an example of a product listing page that doesn't suck (source, blog post)

An arbitrary selection of my smaller libraries

• classy-graph, an exercise in "data-ink maximization" inspired by Edward Tufte.
• sql-concat, for building SQL statements programmatically
• financial-number, for arbitrary-precision arithmetic on financial values
• regex-fun, for writing maintainable regular expressions

Plus hundreds of other JS libraries on GitHub.

Familiar Technologies

• Web front-end
  • AngularJS
  • React
  • Redux
  • Svelte
  • Vue
• Java
• PHP
• C++
• TypeScript
• Databases
  • MySQL
  • SQLite
  • ElasticSearch
  • Redis