A Story of Humanity: The Jess and Dev Tales by Melissa Good
Part 5 and 6

The Story of Humanity: The Jess and Dev Tales is set in the near future post apocalyptic - the earth has been devastated by weather. Human society on the planet is reduced to fighting for survival over seaweed and scraps. Jesslyn (Jess) Drake is a warrior for that time - an agent who works for one of two 'sides' (think cold war) and is sent into conflict to steal scientific secrets or otherwise prevent that 'side' from making advances that would let them prosper. There are no good or bad guys.
Dev is Biological Alternative, set 0202-164812, instance NM-Dev-1 is a type of human being developed on a space station in orbit who can accept direct brain programming to suit them for a specific job and is the first of her kind to be made into an agent to join this side. Has a somewhat slave status and no one really wants them around but is given to Agent Drake who is arm twisted into giving it a try