1 Book Found

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"Looking for a Kindle Unlimited sci-fi series (around 5 books, read circa 2020). First-person narration. Main character starts as a courier pilot on a space station and has a rival pilot from a larger company. A hooded humanoid alien pays him for a delivery with a blueprint for a crystalline ship coating that greatly improves durability. He uses it to build ships in a private moon shipyard, defeats pirates, grows a fleet, and eventually fights aliens. One of his friends becomes a General after losing all four limbs and receiving cybernetic replacements. The fleet liberates a robot-controlled planet. Later, personnel are captured and forced into military simulations inside a giant alien metal sphere. The overarching enemy is a hidden AI that has been manipulating events, and the final books reveal the AI behind the conflict."