I do use both of those protocols, but for this specific use case I'm referring Alchemix. I deposited $30k DAI and borrowed $15k alUSD against the deposit. Traded the alUSD for USDC and withdrew through Coinbase.

I didn't go into detail in the initial post since it sounds a bit crazy, but the loan will actually pay itself off since Alchemix is depositing my $30k into Yearn. The yields generated from Yearn gradually pay down my debt automatically. Other interest bearing positions (apps like Compound and "yield farming" on various new protocols) will also help me pay off the loan faster.

The alternative to this is that I could've taken $15k from the initial $30k and paid off our loans outright. But, using Alchemix is more capital efficient. Student debts are now paid and I also have $30k of capital generating yield instead of only $15k if I had simply paid the loans upfront.

How did you come to trust Alchemix with that much capital? I'm not familiar with them, but just checking their site doesn't give me a lot of confidence about sending tens of thousands of $ to them.

It's all open source. You can see the contracts yourself, or read an audit that someone else created. The beauty is that you don't have to trust them, because you can see exactly what can possibly happen with your money by looking at the code.

I trust people much smarter than myself to evaluate the contracts. Audits from highly reputable firms also help. Nonetheless, there's always risk.

How long does it take until your loan has paid itself off?

My collateral is currently yielding 6.5%, which is gradually paying down the debt. At this rate, estimated maturity is 02/28/2029. This will vary depending on APYs for DAI in the Yearn protocol. But personally, I'll use other income streams to pay it off much sooner.