Week 2 Dig: Stratigraphy

Dating techniques — reading the commit history as geological layers to identify periods of construction, maintenance, and abandonment.

1 March 2027

Before the dig#

Run git log --format='%ai' on your dig site and pipe it through a tool of your choice to produce a commit-frequency graph (commits per week or per month). Any tool works — a spreadsheet, a Python script, a shell one-liner. The graph is the artefact; the tool is not.

Read the graph before the session. Look for:

• Construction phase: high-frequency early commits, often by one or two authors
• Maintenance phase: lower frequency, broader authorship, more merge commits
• Decay phase: sporadic commits, often only dependency updates or CI fixes
• Boundary events: a week with an unusual spike or drop. What happened?

In the session#

Present your timeline. Name the phases you see and the boundary between the last active period and the decay. The class pressure-tests your reading: is that spike a release, a rewrite, or a weekend? Is the silence after it abandonment or stability?

Afterwards#

Write a 200-word stratigraphic summary of your dig site: when it was built, when it was maintained, when it was abandoned, and what (if anything) the boundary event appears to have been. Cite specific commits.