The other replies here are misguided. A senior developer's job is not to take over as a know-it-all dictator at the end of their first week. You don't write uni

The other replies here are misguided. A senior developer's job is not to take over as a know-it-all dictator at the end of their first week. You don't write unit tests for existing code, refactor other developers' work, take over the role of architect or sysadmin, make sweeping changes to existing processes, or take any other "heroic action". The number of comments here essentially saying "assert your dominance by introducing the 'right way of doing things'" is unsettling. Shame on anyone who strolls into a new team with this mentality. Your job is simple: get to work. You don't invent "important senior work" for yourself as a way to prove your merit with your ego, before you have settled in and earned your title. You pick up existing tickets from the queue. The only way to get acquainted with the project and its stack is to begin working on real tasks that require minimal modifications to the codebase. That's your goal: commit and deploy small chunks of code that accomplish something useful for the business. You need to take the time to organically discover each subsystem, one at a time, as you complete tasks that actually close tickets. A senior developer's initial job is to be a "junior developer" who knows nothing about the project, taking the time to learn the system bit by bit. Progressively pick up enough knowledge in order to eventually be in a position to assist other developers and make decisions about the project's future. After 1-3 months, depending on the size and complexity of the project, you will have touched a majority of subsystems while working on tasks. You will then have a comprehensive understanding of the system as a whole, and may be considered informed enough to take some amount of control over the future direction of the project. tldr; Your job as the newest senior developer on a team is not to be perceived by others as a senior developer. Your job is to act like a senior developer, and that means taking the time to integrate yourself at a reasonable pace. The "Senior" prefix to the title does not kick in until you've worked on the codebase long enough to fully understand it.