Bringing System to Great Tang

Novel Summary
Li Yi passed through, with a lifespan system. Only by doing things that were conducive to the social development of the Tang Dynasty could lifespan be increased.
At this time, his life span was calculated by hours, and then he met Emperor Li Longji who had concealed his identity from him.
The story begins here.
Li Yi: As long as it can increase my lifespan, I have all the skills needed.
– Description from readMTL