This is a book I read in 1992. I thought the title was Nth Space, or N-Space, but the only listing I was able to find anywhere close to that was a collection of short stories.The story centers around a civilization that uses space ships to navigate the ripples in the fabric of space / time that are formed by a star's mass. Each of these ships is a powerful computer that is linked to the brain of the pilot. The dilemna they must overcome is some unkown civilization, that lacks their sophistication for navigating these ripples, is blowing up stars, which straightens out the folds, which greatly simplifys the problem,but destroys whatever life form is living in that star system. So they must find out who is doing this and stop them.Their civilization has divided different disciplines into guilds. Of the many specialties, there is a guild for Space Navigation, one for memory, and even one for semantics.One particular guild I remember is the gene shapers. this guild use the knowledge of genetic engineering to do just about anything, from correcting conditions to making complete anatomical changes. An example is a fad of morphing one's body into hybrids of animals. A practice that is similar to fringe groups we have here on earth that uses tattoos and dental shaping to make themselves appear like Tigers or Lizards. However, in the civilization of this book they take it to a deeper level. I give this background because one of the supporting characters, unknowingly, earns the ire of one of these gene shapers; and while getting some work done, the gene shaper leaves him a little easter egg in his coding. If that, soon to be unhappy, character gets an erection after sundown, he's stuck with it until sunrise.
The universe of Neverness is and filled with extraordinary beings, such as the neanderthal-like Alaloi and the Order of Pilots. Against this backdrop stands Mallory Ringer, who penetrates the Solid State Entity. There he makes a discovery. One that could unlock the secret of immortality.