I'm tempted to use this stack on a new project but I worry about MongoDB since data in this application is critical and loss would be catastrophic. Is it possible to substitute Postgres or something with atomicity?
Or maybe MongoDB has ironed out the problems that were listed on HN previous...
> but I worry about MongoDB since data in this application is critical and loss would be catastrophic
Don't worry, this is just some old and well debated prejudice against Mongo (don't want to start a mongo discussion here though). Mongo has five different safe write modes you can choose from plus optional journaling and is in general some of the most impressive piece of tech and the best document store I know. Just try it and you won't go back and it's popular: http://www.google.com/trends/explore#q=mongodb%2C%20postgres...
Though Postgres is a great DB and supports JSON directly you get just a fraction of the query possibilities you have with Mongo. With Postgres you get some basic operations for the JSON data type (since the JSON support is added recently, think 12-18 months ago). So, I wouldn't consider it as a real substitute to Mongo.
I like it because I get
- high responsive / low latency sites
- fast ramp up time thanks to Mongo, no schemes, no migration, just JSON everywhere; JS objects are one of the most flexible data types
- more than just a key value store, a powerful document store with query capabilities close to SQL DBs (Mongo)
- an ecosystem where performance is important (e.g. tons of on performance trimmed templating engines like doT)
- just one language to get good in (JS)
- fresh, highly modular concept and no aged, outdated design patterns from 2005 legacy, bloated, monolithic web frameworks
- lightweight, lightweight, lightweight
- instant startup time of the VM
- no compilation
- a language implementation with C class performance (V8)
- Easy to find talents which can work on all parts of the system => real full stack devs
- a lightweight, unobtrusive FE framework which doesn't stand in your way (Angular)
- best package manager out there (npm)