For these technical jobs you have just mentioned the easiest way to build a job description (JD) is to give this task to the job holder themselves,
• Let them list what are their day to day tasks
• Let them list what are their monthly tasks
• What are their on going projects, planned
• What are their obtained qualification to do the job
• What are the other required qualification certification to do the job
• What are the technical skills required to do the job
Then from the list of tasks you can build a generic job description of the position starting form senior position cascading to junior positions.
As Anayat have shared please do consider those suggestions. Additionally here's few pf mine:
- Make a study including the both desired and required parameters for your sector.
- Identify the keywords used to define by the industry leaders and your competitors.
- Identify a format to be used which suits your organization the most.
- Include the write-up that you could develop with Anayaat's directions.
42 Job description zip