show and tell for hackers in DC.

Round 68: Roomba on the Loose

16 May 2019

Big thanks to WeWork for hosting.

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Event link:

Notes copied directly from the hackpad!

Owen Diehl


A tool for declaratively automating https certificates for small projects, powered by letsencrypt. “Automating HTTPS for small projects” Encryption is important! Let’s Encrypt! Yes, let’s! But still annoying: How do I get this certificate? How do I renew? Docker container to handle everything for you!


Config file for use with docker compose! Good for nginx! Uses under the hood. Seems like it handles a lot of annoying work!

Travis Hoppe: Greasepaint

A python library to add makeup and other body modifications to your photos

Brand new library! Very important stuff! Or possibly silly!


Glam rock! Whammy bar! Also makeup! Very skill! Now: Makeup on your face! With Python!

> pip install greasepaint

from greasepaint import eyeshadow

Based on pixelhouse? Poisson image editing, y’all. More glam tho! For the US Senate! Writing a graphics library is fun and exciting! Five lines in pixelhouse! Person Ghost!

Frankie Abralind

People will tell their secrets to poets.

Free Custom Poetry! Art project became a full-time job! Non-profit to encourage good listening in hospitals! People tell their secrets because they’re good listeners: “I’m a poet. Can I write you a poem?”

Example from a doctor at Sibley Memorial Hospital - you can get the book and read it to! “Maybe that’s what therapy is like; I don’t know.” Maybe more people should take advantage of therapy! Helping doctors, nurses, and patients! Find them online!

Poets all over! Poets the hospitals! “When a tiger fights, she fights!”

Charles Lyons

Basic background on the Nova Labs makerspace in Reston

Lots of resources for lots of kinds of hacks!

Robotics! Blacksmithing!

So many events happening every work! Requires taking their classes to get signed off on machines; safety and competency! Autonomous collective! “A support group for creative people” Anvil in the parking lot. Different from TechShop

Brian Cohen: Pleochroism

Automatically generating color schemes with Pleochroic

Parameterized color scheme generator Can you control every aspect of your computer? Maybe not!

Characteristics that are useful for a color scheme. Color science. Red/Green/Blue pixels blend together to make a color your eyes can see. Can have the same lightness value but different colors.

Yellow can be as bright as blue, but it doesn’t look that way Gettin’ into your eye! Cones receiving frequencies! Trying to make a good design! It’s not easy! Where is that best color scheme? Interact with some sliders!

Primary color offset! Invert it to be funky! Whole presentation in Julia! Has return types with v1. With Julia2, maybe inductive data types with pattern matching? Oomox for GTK theming! Using interact library for Jupyter sliders.

Eric Haengel

I’m following up on a previous talk I gave about an audio modem I built. I’m working on v2, and it is a work in progress but I have some mostly working hardware to demo for everyone.

Audio Modem v2! Oscilloscope in the place! Communicating from computer to computer via audio! Project started a year ago! Now: Custom hardware!

THERE’S A BLOCK DIAGRAM Livin’ in a voltage world, y’all. Eric made his own printed circuit board, because of course he did “I have a cat, and she’s very sensitive to ultrasound, apparently.” Lots of companies who will make a circuit board for you.