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This procrastination issue has a long buildup, but I will try to explain it briefly. I was working on a large project with a senior programmer in a language/methodology I was new to. About half-way through the project, the senior programmer left the job and the project was now all in my hands.
Fast forward a month and I have a fairly good working program, which is great. The unfortunate issue is that now I am tasked with implementing the program into other projects, which I have no clue on how to do. Mixed with looking for a different job (unrelated to this project, but related to the job), I have unwittingly procrastinated on working on a solution to my issue.
Now I have a deadline that I know I will most likely not meet. Should I explain to my manager that I am further behind that he may believe and that I have messed up, or should I just work extremely hard on finding a solution and deal with the mess-up at deadline time?