Story about an AI dreadnought trying to avenge the destruction of Earth

Question

This is a story I read in the past couple years. It was too long to just be a short story in a collection, but I don't remember it having cover art or anything.

It centers around an AI dreadnought that failed to save the Earth from aliens. Its crew all died in the last battle before Earth was destroyed. The dreadnought has spent thousands of years making guerrilla raids on the aliens' territories, with pauses to repair & improve itself.

The aliens are an expansionist multi-racial federation, with semi-religious veneration of the "leader" race, kind of like Halo's Covenant or Warhammer 40k's Tau. There are still some humans around because the aliens initially missed a colony and found it later; the humans don't know the aliens were responsible for the destruction of Earth and are now an (oppressed?) minor member of the alien federation. Only the top echelons of the alien federation know about the ship because they cover up all its attacks for propaganda reasons; the leaders hate the ship and call it the Wound.

The story is a mix of naval combat as the aliens try to kill the ship, flashbacks to the past, and a longish section where an alien ship with some human crew finds & boards the dreadnought, thinking to salvage it because nobody on the ship is a high enough rank to know about the Wound.

Answer 1

Is it possible you don't remember a cover because you read this story online?

This sounds like it could be The Last Angel.

A Web Original work by Proximal Flame first published on Spacebattles Forum in December of 2012. ... The story opens with the the death of a Compact Chariot at the hands of the first Human Dreadnought. The Compact is a collection of alien species that seeks to conquer Humanity and absorb them into their ever expanding empire. They outnumber and out-gun Humanity, and their flagships, the Chariots have never been defeated. Nemesis breaks that streak, being the first to slay a Compact Chariot in combat. Despite this Nemesis is nearly crippled and her crew decimated. Oh, and one Compact ship gets away with Earth's coordinates. Cut to two thousand years later. The Compact has continued to grow and advance, and all that remains of Humanity is Rally, a single colony the Compact has found, whose population has long since been culturally subverted into loyal citizens. ... Aboard Bequeathed, Grace has to deal with a lecherous and sadistic superior officer while Allyria is routinely put down by the ship's Tribunes, who are still holding a grudge over how much trouble the Verrish gave their invasion force. Then Bequeathed stumbles upon a massive alien derelict in a remote star system. It's the find of the lifetime, and the Bequeathed's captain wants to take the credit. Salvage teams are sent to board it and evaluate the technological treasures within.

The story can be found here.

Answer 2

If it might be an online story, it could be "Chrysalis", by beaverfur.

A giant machine made by humans before they were all wiped out wakes up years later, tries to remain undetected and finds some aliens lurking around and decides to nuke them. In the process, she learned they are some kind of aliens who are part of a galactic council, then more ships come to Sol and the machine makes a boarding attempt and captures the battleship/dreadnought.

The third chapter skips to some aliens talking about politics.