I'm an Australian citizen, software developer planning to move to Germany. I know that as an Australian citizen I'm allowed to stay in Germany for up to 90 days. But it looks like to get a job I need to apply for residence permit first. Or is it the other way round? Maybe someone has more detailed steps up to a point where you got the job.
Australian citizens can apply for a residence permit after entering Germany at the local immigration authority, without applying for a visa beforehand.
You won’t be able to start work until the work permit has been issued. This means that legally one is allowed to sign a working contract without any residence or work permits or visas, but needs both residence permit and work permit on the first working day. However, in rare cases this might be misunderstood by the employer, e.g., you might be asked during job interview if you already have work permit. For such cases, try to handle it nicely explaining that the normal process of getting it requires a signed job contract and that you have a very good chances of getting a residence permit (especially after new Fachkräfteeinwanderungsgesetz was introduced on 01.03.2020).
If you want to start working immediately after your arrival in Germany, you should apply for a visa about 8-10 weeks prior to the intended departure.