altcoin price alerts (node.js, python or php based) -- ...

i'd like to get cryptocurrency exchange price change alerts based on adjustable settings. Additional details to be provided to qualified applicants who know the subject matter well and can therefore work time-efficiently. Please briefly summarise your experience with bitcoins and other cryptocurrencies, especially with altcoin exchange api's. I'm open to any approach/language (php, python, node.js, etc.) that provides alerts that are as close to real-time as possible