Median JIRA Resolution Latency
establishedn/a
insufficient data
Based on: CHAOSS: Issue Resolution Duration, CHAOSS: Change Request Closure Ratio (adjacent)
Automated, reproducible metrics for Apache Cassandra easy-stress.
Code and contributor health metrics: sustainability, review capacity, and responsiveness — computed from Git, ASF JIRA and GitHub PR history.
Faint points mark a month flagged low-n or insufficient data —
its statistic (a rate, an HHI, a median) comes from too few underlying events to be
reliable on its own. Hover a point for its exact n and flag; the value itself is unchanged.
n/a
insufficient data
Based on: CHAOSS: Issue Resolution Duration, CHAOSS: Change Request Closure Ratio (adjacent)
n/a
insufficient data
Based on: CHAOSS: Issue Resolution Duration
n/a
insufficient data
Based on: CHAOSS: Change Requests (adjacent), CHAOSS: Change Requests Declined (adjacent)
insufficient data
insufficient data
Based on: CHAOSS: Change Requests (adjacent)
n/a
insufficient data
Based on: CHAOSS: Time to First Response, CHAOSS: Responsiveness practitioner guide
insufficient data
Based on: CHAOSS: Change Requests (adjacent), CHAOSS: Change Requests Declined (adjacent)
insufficient data
Based on: CHAOSS: Change Request Closure Ratio
n/a
insufficient data
Based on: CHAOSS: Change Request Closure Ratio
insufficient data
Based on: CHAOSS: Issue Response Time, CHAOSS: Time to First Response
0.143 Apr 2024 backfill pending
Based on: CHAOSS: Issues Closed (adapted)
insufficient data
Based on: CHAOSS: Time to First Response (GitHub-only variant)
How quickly a patch submission gets its first visible review response, split by how many
prior submissions the same contributor has -- a first-time submitter, a 2nd-5th submission, or
a 6th+ submission. A "submission" is one JIRA issue that ever reached
Patch Available, together with any linked GitHub pull request. "First visible
response" is the earliest of a JIRA comment, a JIRA status change to
Review In Progress/Ready to Commit, or a GitHub PR review/comment,
from someone other than the submission's own author -- review that happened somewhere this
project doesn't track (a private message, an in-person conversation) is invisible to this
section, so "no visible response" means exactly that, not "no response at all."
Methodology and caveats. The submission's author is reconstructed from JIRA's assignee-change history, which is a best-effort proxy, not a confirmed identity. Shares for "response within 7/30 days" and "no visible response" only count submissions old enough to judge (right-censoring: a submission newer than 7, 30, or 365 days is left out of that share's count entirely, not counted as a miss). These figures are informational only, shown with their own sample size (n) for context. Full definitions: METRICS.md.
History still loading: the Patch-Available changelog backfill hasn't started yet, so author tiers and shares below are not yet trustworthy.
Review responsiveness isn't published yet -- it appears once the Patch-Available changelog backfill has collected enough JIRA history for this project.
The open apache/cassandra PR backlog by age and by linked-JIRA-ticket state, reconstructed monthly. Scoped to apache/cassandra: other configured repos use their own issue tracker or none, so ticket-key state isn't meaningful for them — see the table below instead.
| Month | Open PRs | Drafts | No GitHub response |
|---|---|---|---|
| 2026-09-30 | 2 | 0 | insufficient data |
Based on: CHAOSS: Change Requests (adapted), CHAOSS: Issue Age (adapted, applied to change requests)
Base branch (trunk vs. release branches) is not collected yet, so it is not shown here.
0 Sep 2026
Based on: CHAOSS: Contributors
0 Sep 2026
Based on: CHAOSS: New Contributors
insufficient data
Based on: CHAOSS: Conversion Rate
insufficient data
Based on: CHAOSS: Conversion Rate (adjacent), CHAOSS: New Contributors (adjacent)
insufficient data
Based on: Lin, Robles & Serebrenik (2017), Developer Turnover in Global, Industrial Open Source Projects, Foucault et al. (2015), Impact of Developer Turnover on Quality in Open-Source Software
71.4% Aug 2025 backfill pending
Based on: project-specific (no established CHAOSS/literature equivalent)
1 Sep 2026
Based on: CHAOSS: Contributors (adjacent)
1 Sep 2026
Based on: CHAOSS: Contributor Absence Factor / Bus Factor (adjacent), Avelino, Passos, Hora & Valente (2016), A Novel Approach for Estimating Truck Factors
1 Sep 2026
Based on: CHAOSS: Contributor Absence Factor
0.531 Sep 2026
Based on: DOJ/FTC: Herfindahl-Hirschman Index
n/a
0 Sep 2026
insufficient data
Based on: project-specific (no established CHAOSS/literature equivalent)
insufficient data
Two additional views of the cards above: a Kaplan–Meier survival curve over contributor tenure, and a per-stage breakdown of the latest completed first-time-contributor cohort's funnel. Both are computed from git commit history only; the committer and PMC funnel stages are not available (no confirmed identity link between the ASF roster and this project's git/JIRA identities exists yet).
Cohort size (n=7) is below the 30-contributor floor for a Kaplan–Meier curve; showing a still-active count instead.
| Months since first contribution | Eligible | Still active | Share |
|---|---|---|---|
| 3 | 7 | 7 | 100.0% |
| 6 | 5 | 5 | 100.0% |
| 12 | 4 | 4 | 100.0% |
| 18 | 2 | 1 | 50.0% |
| 24 | 1 | 0 | 0.0% |
The contributor funnel isn't published yet.
n/a
Top contributors by one activity type at a time — commits, reviews, and JIRA issues resolved — over the trailing 12 completed months (2025-10-01 to 2026-09-30). These are ranked counts of deterministic, public activity, never a blended "contribution score" and never based on any classified label (DECISIONS.md — D19).
Identity-resolution limits. Counts are grouped by resolved identity (normalize/identity.py), not by human being. M0's identity resolution only merges an exact-matching git email or JIRA username; a commit-trailer reviewer name (a bare handle or display name, not an email) is never automatically linked to that same person's git email or JIRA username, so one contributor active under more than one raw identifier can appear more than once, or under a handle rather than their full name. Manual merges are reviewed, evidenced entries in identity_overrides.yaml -- see the corrections link below to request one. Request an identity correction (every row's own "Report an issue" link below uses this same form) — see /corrections/ for what happens next.
| # | Contributor | Organization | Count | |
|---|---|---|---|---|
| 1 | Jon Haddad | Apple | 10 | Report an issue |
| 2 | The Apache Software Foundation | unknown | 1 | Report an issue |
| 3 | dcapwell | unknown | 1 | Report an issue |
| 4 | samlightfoot | unknown | 1 | Report an issue |
| 5 | Stepan Nazarov | unknown | 1 | Report an issue |
| # | Contributor | Organization | Count | |
|---|---|---|---|---|
| 1 | Jon Haddad | unknown | 2 | Report an issue |
| 2 | Yifan Cai | unknown | 1 | Report an issue |
insufficient data
insufficient data
Based on: CHAOSS: Elephant Factor, CHAOSS wg-risk: Elephant Factor
insufficient data
Based on: CHAOSS: Organizational Diversity
insufficient data
Based on: CHAOSS: Organizational Diversity
28.6% Sep 2026
Based on: project-specific (no established CHAOSS/literature equivalent)
PMC membership is tracked once for the whole Apache Cassandra project via the shared ASF roster, not per subproject. See Apache Cassandra's Community page →
3 Sep 2026
Based on: CHAOSS: Release Frequency
1.414 Sep 2026
Based on: project-specific (no established CHAOSS/literature equivalent)
595.0 days Oct 2026
Based on: project-specific (no established CHAOSS/literature equivalent)
12.0 h Sep 2026
Based on: CHAOSS: Release Frequency
Conversation patterns are classified from the dev@ mailing list, shared across all Apache Cassandra subprojects — not computed per subproject. See Apache Cassandra's Conversations page →