This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.
To capture the video (filesize: 19MB), using the free "QuickTime Player" application:
| # The initial version | |
| if [ ! -f .env ] | |
| then | |
| export $(cat .env | xargs) | |
| fi | |
| # My favorite from the comments. Thanks @richarddewit & others! | |
| set -a && source .env && set +a | 
| FROM ubuntu:14.04 | |
| MAINTAINER Seonghwan Lee <[email protected]> | |
| RUN cd /etc/apt && \ | |
| sed -i 's/archive.ubuntu.com/kr.archive.ubuntu.com/g' sources.list | |
| RUN apt-get update | |
| RUN apt-get install -y git curl python | |
| RUN apt-get install -y ruby2.0 ruby2.0-dev |