Flash Boys is a great book and we required our new hires to read it as it got a lot of things right.
Front running is illegal now, but arbitrage opportunities still exist between exchanges. Being fast is still an easy way to make money.
You're right about dark pools though. Those are the future (honestly they are already up and functioning) and they hide trading activity very well.
Front running has always been illegal.
Arbitrage is not illegal. Latency arb certainly isn't easy.
"Dark Pools" is a book. It's also a thing, but that's obviously not what I was talking about.
There's nothing especially shady about dark pools. We'd call them "private exchanges" if the exchanges weren't themselves already private companies, I think.
Nowhere did I imply that arbitrage is illegal and latency arbitrage is a big driver of revenue for several hedge funds, especially those which track baskets against their components.
There isn't anything shady about dark pools, except that there is little public information about the trades which take place within them, they are sparsely regulated, and you have even less insight into your counter parties than you do on open exchanges. And my response referencing dark pools was a response to your comment about execution services.
Being fast is not an easy way to make money. It's an incredibly hard and difficult way to make money. I don't know what kind of HFT you worked at, but I guess you just plugged in a laptop to a GBit/s network line and plugged away making "easy" money?
Also, the first dark pool was created in the 80s, so you're a little late on that development as well.
And once you are fast, you have to stay fast. Remaining fast is not easy or cheap either.
Sure, if you have the part that’s really hard to get right, making money is then really easy.