The industry I work in has many many companies. For whatever reason they all seem to use a very similar website template. Job openings are almost always listed on their webpage. Almost always its a plugin from workday or whatever their HR software is. Years ago I noticed that job listings were almost always published to their websites before they appeared on major job sites like linkedin.
I used a business to business website that lists every single company in this industry by location and has a link for each to generate a list of companys and URLS. I monitor this for changes with changedetection.io
Then changedetection.io + company list and their job posting URLS that look like this company.com/careers/join-us/?_sft_job_posting_category=technical
So I now have about 800 companies that I am able to monitor for job leads and get notified via NTFY with company, job title and job description.
Its turned off currently cause I am actively employed, but when I was looking about a year ago I had it running hourly and if I look again I will indeed use it