When I heard the term "stablecoin", my first thought was about George Soros. Most people don't know his early history. In 1992, he crashed the British pound for a $1 billion profit in a few days.
Currency pegs are notoriously difficult to maintain. They create predictable behavior and predictability can be exploited. Look at this Demand/Supply/Price chart...
I expected in 2019 that there would be Soros-style attacks on crypto-currencies. A stablecoin is a currency peg. For price to remain the same, increased demand is countered with increased supply. Otherwise there are... shortages! Shortages create dysfunctional behavior because coins aren't available, which creates timeouts, unpredictable failure cases, etc.
Many "algorithmic coins" are designed to increase coin supply during a demand spike. The assumption is that those coins will be backed with deposits or burned after the demand spike ends.
The demand response is a unique time-based function for each coin. In theory, you can arbitrage their behavior differences.
If you don't understand basic concepts like this, you probably shouldn't be writing (or buying or funding) a crypto currency.
1) Cap incoming demand at 3 or 5% growth rate. Sure, you may lose a few customers but you won't lose your platform.
2) Cap rate of coin creation at 2 or 3% per day. Duh. You may get glitchy behavior but you'll know why.
3) Force deposits to back coins first. That's what banks do.