Senior Analyst/Developer expected bonus?

I recently accepted a position as a Senior Analyst Developer at Goldman Sachs in Middle Office. From what I understand, I'll be working on post-execution trade processing and some pure tech-heavy things (haven't started yet).

I come from a non-finance background, and during the interview process everybody kept telling me that they measure compensation in terms of "total comp" (i.e. base + bonus), I thought to brace me for a lowball base salary offer. Thankfully, they gave me a bit of a bump on my base, so I gather they were being honest about the total comp stuff. But I don't have any idea what type of bonus I can expect to receive. Does anybody here know? The bonus is written into my offer letter, but it's worded intentionally vague -- "you'll be eligible for a discretionary bonus" -- so I don't even know if I can count on it.

I turned down a couple other decent offers from big names to work with Goldman and I want to avoid having buyer's remorse.

Thanks!

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