If I can handle being melee on my Mesmer, Elementalist, Thief, and Ranger, I'm sure I can handle being melee on the Engineer.
Especially with Adrenal Implant and Adrenaline Pump!
Frankly, I'm getting tired of hearing, from
every single profession, that they're squishy and can only survive less hits than they have fingers on one hand. Because I've experienced that kind of "squishy" on every single profession, including Guardian and Warrior. That's the way the game is designed - you're not meant to survive taking direct hits... not for very long anyways.