I have been working for a kashrut rabbinical organization as a mashgiach for over a month and a half. They are extremely satisfied with my work and have told me so. Originally, I replaced the regular mashgiach who was on vacation and was asked to come in for just one week. Ever since, they call me every week to inform me to come in just for the following week. I finally asked them if I could have the job permanently, and they said that they would continue calling me every week. I cannot budget this way and with the uncertainty. I have never heard of any company or employer acting this way with an employee. Is there any halachic justification to the way I am being treated? Is there anything I can do?
While this is certainly a difficult way to be employed, there is no halachic obligation for them to hire you in a permanent way. However, you are certainly not required to work in such a way, and can use your good work as a bargaining chip, i.e. to give them some kind of ultimatum and time frame for permanent hiring after which you will discontinue any other form of employment.