Where the postings actually live
Most companies hire through an applicant tracking system whose listings are openly readable: Greenhouse, Lever, Ashby, Workable, SmartRecruiters and Recruitee between them cover a large share of software employers. A company appears on one of them, so five of six will correctly have nothing for any given company.
Reading the boards directly is better than reading an aggregator. The dates are the company own, the text is unedited, and nothing has been deduplicated away.
Counting, not reading
The signal is the shape of the hiring, not the content of one posting. Count postings by function over a rolling two-week window and look for clusters: four sales roles at once means a number was set and a team is being built to hit it.
A single role is usually a backfill and rarely worth acting on. Three or more in one function inside a fortnight is a project.
Separating growth from replacement
Three tells distinguish expansion from churn. New titles that did not exist at that company before indicate a new capability. Several roles at the same seniority posted together indicate a team build rather than a departure. A location that is new for that company indicates expansion.
Conversely, one senior role reposted after a few months usually means a failed search or a departure, and it is not a buying signal.
Reading the text, once the count says to
When a cluster fires, the postings themselves are the richest free document a company writes about its plans. They name the tools the team will use, the problems the hire is expected to solve, and often the manager the role reports to. That is your qualification and your angle, in the company own words.