Dane Hartman | Software, teaching and media

Featured software

I took these apps from idea to release. I designed the interface, shaped the architecture, tested every build, and set up the store listings, payments, error tracking and hosting, working with Claude as my coding agent.

Across these projects: Cloudflare, Paddle, Sentry, Healthchecks.io, Photoshop

KaraokeSmith

Windows desktop app · 2026

Give it an MP3 and you get a karaoke video back. It separates the vocals, transcribes the lyrics and times every word, then opens an editor where you fix whatever the AI got wrong before it exports an MP4. Your audio stays on your PC. I designed the interface and supplied the artwork, directed Claude Code to build it, and tested it on six hardware setups and dozens of fresh virtual machines. A small Cloudflare Worker handles licensing: Paddle takes the payment, the Worker verifies it and emails the key. A security review of that Worker found three defects, including refunds that did not revoke licenses. All three are fixed.

Remotion, FFmpeg, Python, FastAPI, Cloudflare Workers, Paddle, Resend

Visit karaokesmith.com ▸

TagSmith

Windows desktop app · Microsoft Store · from December 2025

I wanted a power-user tool to manage photo metadata and quickly geotag photos. Existing software was clumsy, so I built TagSmith. TagSmith allows you to quickly fix dates, locations and keywords stored inside photos and videos. It can time-shift bad camera clock settings and extract dates from filename patterns. With a built-in offline GPS database of 68,000 cities, reverse geocoding, and nearest-neighbor GPS propagation, it makes bulk geotagging your photos quick and easy. TagSmith credits can be purchased to unlock Gemini-powered AI landmark identification, which geotags your photos based on their contents. Available on the Microsoft Store.

The optional AI feature runs on a small Cloudflare backend that tracks prepaid credits and takes payment through Paddle. A monitor checks every 15 minutes that anyone who pays actually gets their credits.

Electron, React, TypeScript, ExifTool, Cloudflare Workers, D1, Paddle, Resend, Healthchecks.io

Visit tagsmith.app ▸

UIMA website

Freelance rebuild · live October 2026

A museum's Squarespace site, rebuilt in 17 days. 83 exhibitions and 273 events came across with their photos, and every old address redirects to the right new page. I produced three design options for the client, then subvariations of their preferred style until a final design was chosen. I handled the migration and directed the build. When the client requests a change, I make and deploy it, often within minutes.

Visit uima-chicago.org ▸

More software

Code.org AutograderGrades Code.org projects against a rubric and emails each student the result. I wrote all 74 criteria to steer the LLM, and I used it with my own classes for two school years. It grades consistently and students get immediate feedback.Open source

GC → IC Grade TransferTeachers often have to manually transfer grades from one system to another. Some districts pay for a Chrome extension that does that automatically, but it can cost over $70,000 per year. When my district stopped paying, I decided it was time for Claude and I to build a free version. I've been in touch with teachers across the country that are now using it, and I've shipped nine versions, pushing updates to ensure that it continues to work even when IC changes its gradebook structure.Free Chrome extension

Games I coded myself

I wrote Pac-Man, Tetris and Asteroids before LLMs existed and used them as the basis for coding lessons.

Pac-Manp5.js, with two extra maps · Play ▸

Tetrisp5.js · Play ▸

Asteroids 3DUnity, desktop browsers only · Play ▸

Learning and media

I make videos for my own students and put them on YouTube. The file-management one has passed a million views, and educational institutions have asked to reuse it.

More on my YouTube channel, including the rest of the Computer Skills Course ▸ (opens in a new tab)

How I teach

I design lessons with the scaffolding necessary for students of all levels to learn and succeed. Hints come first, and a student only sees the solution if they get stuck. Every unit has a rubric students can check their own work against. I also built a digital literacy boot camp that grew over about ten years, and I've led staff sessions on AI and classroom technology, including one for a whole district. On contract through Zenith Performance Solutions I built e-learning modules in Articulate Storyline for corporate clients and delivered them as SCORM packages, working with subject matter experts.

Side projects

Some lighter projects I made for fun.

D2LOL, the assignment dropbox that talks backA parody learning platform. You drop in an assignment you already turned in, and an AI grader called Professor Redpen reads it, compliments it, then roasts it. Built with my SAIT hackathon team.Try it live ▸

KaraokeFix on YouTubeMy karaoke channel. Most of the videos on it were made with my own KaraokeSmith software.Watch on YouTube ▸

The Shawstache RedemptionA Movember film I made for the annual mustache contest at Wheat Ridge High School.

Photography

I studied photography as an undergrad. Here is some of my work.

See all photos (34)

Under the hood

I'm old-school about computers. I started in Norton Commander, and now use Total Commander. I bulk-rename with Advanced Renamer and regular expressions, and I'm comfortable working in the Windows registry. I build PCs, image lab machines over the network, run a Mac imaging server, clone drives using a Linux USB stick, and keep redundant backups of everything that matters.

Say hello

Questions, or want to use one of my videos in your course?

Send a note and I'll answer it myself. You can also find me on LinkedIn (opens in a new tab).

Software and media, built end to end.