Community — Apache Cassandra Python Driver · Project Health

asf_roster: not_applicable git: ok github: ok github_commit_authors: ok github_issues: not_applicable github_profile: ok governance: not_applicable jira: ok ponymail: not_applicable release: ok release_lines: not_applicable security: ok subproject_releases: ok

Code and contributor health metrics: sustainability, review capacity, and responsiveness — computed from Git, ASF JIRA and GitHub PR history.

Charts default to the last 3 years.

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.

Responsiveness CHAOSS practitioner guide

Time to First Response (JIRA) insufficient data
Stale PR Rate 82.4% Oct 2026 · n=17
Open PR backlog 16 Sep 2026 · n=16
Median JIRA Resolution Latency insufficient data

Responsiveness

Median JIRA Resolution Latency

established

insufficient data

Based on: CHAOSS: Issue Resolution Duration, CHAOSS: Change Request Closure Ratio (adjacent)

Median JIRA Resolution Latency (12m cohort)

established

insufficient data

Based on: CHAOSS: Issue Resolution Duration

Stale JIRA Issue Rate

established

56.2% Oct 2026

Based on: CHAOSS: Change Requests (adjacent), CHAOSS: Change Requests Declined (adjacent)

PR Merge Lead Time

proxy

4.0 days Jun 2026 backfill pending

Based on: CHAOSS: Change Request Closure Ratio (adjacent)

PR Time to Close

proxy

2.5 days Jul 2026

Based on: CHAOSS: Change Requests (adjacent)

Time to First Response (JIRA)

established

insufficient data

Based on: CHAOSS: Time to First Response, CHAOSS: Responsiveness practitioner guide

Stale PR Rate

established

82.4% Oct 2026

Based on: CHAOSS: Change Requests (adjacent), CHAOSS: Change Requests Declined (adjacent)

Change Request Closure Ratio — GitHub PR

proxy

1.000 Jul 2026

Based on: CHAOSS: Change Request Closure Ratio

Change Request Closure Ratio — JIRA Patch Submissions

established

insufficient data

Based on: CHAOSS: Change Request Closure Ratio

Time to First Response (GitHub issues)

established

n/a

insufficient data

Based on: CHAOSS: Issue Response Time, CHAOSS: Time to First Response

Issue Closure Ratio — GitHub Issues

proxy

n/a

insufficient data

Based on: CHAOSS: Issues Closed (adapted)

Reviewer Capacity

PR Time to First Review

proxy

4.3 days Apr 2026 backfill pending

Based on: CHAOSS: Time to First Response (GitHub-only variant)

Review responsiveness

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.

First-time submitters

Year	Submissions	Median days to first response	≤7d	≤30d	No visible response	Committed ≤365d
2025	1	insufficient data	insufficient data	insufficient data	insufficient data	insufficient data

2nd-5th submission

Year	Submissions	Median days to first response	≤7d	≤30d	No visible response	Committed ≤365d
2025	0	insufficient data	insufficient data	insufficient data	insufficient data	insufficient data

6th+ submission

Year	Submissions	Median days to first response	≤7d	≤30d	No visible response	Committed ≤365d
2025	0	insufficient data	insufficient data	insufficient data	insufficient data	insufficient data

Source of first response (2025 and later tiers combined)

Source	Count	Share
GitHub PR comment	1	100%

Open PR backlog

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.

By age — apache/cassandra (last 36 months)

By linked-ticket state — apache/cassandra (last 36 months)

Current month — apache/cassandra

Month	Open PRs	Drafts	No GitHub response
2026-09-30	16	0	56% (n=16)

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.

Contributor sustainability CHAOSS practitioner guide

Active Contributors 0 Sep 2026 · n=0
New Contributors 0 Sep 2026 · n=0
Contributor Dependency (N for 50%) 2 Sep 2026 · n=13
Unique Reviewers 0 Sep 2026 · n=0

Contributor Sustainability

Active Contributors

established

0 Sep 2026

Based on: CHAOSS: Contributors

New Contributors

established

0 Sep 2026

Based on: CHAOSS: New Contributors

First → Second Contribution Conversion

proxy

40.0% Jun 2015 backfill pending

Based on: CHAOSS: Conversion Rate

Contributor Funnel Conversion

proxy

0.0% Jun 2015 backfill pending

Based on: CHAOSS: Conversion Rate (adjacent), CHAOSS: New Contributors (adjacent)

Contributor Tenure (Kaplan–Meier)

experimental

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

Contributor Churn Rate

proxy

70.0% Aug 2025 backfill pending

Based on: project-specific (no established CHAOSS/literature equivalent)

Sustained Contributors

established

1 Sep 2026

Based on: CHAOSS: Contributors (adjacent)

Truck Factor (DOA)

experimental

3 Sep 2026

Based on: CHAOSS: Contributor Absence Factor / Bus Factor (adjacent), Avelino, Passos, Hora & Valente (2016), A Novel Approach for Estimating Truck Factors

Contributor Dependency (N for 50%)

established

2 Sep 2026

Based on: CHAOSS: Contributor Absence Factor

Contributor Concentration (HHI)

established

0.236 Sep 2026

Based on: DOJ/FTC: Herfindahl-Hirschman Index

Reviewer Capacity

Unique Reviewers

proxy

0 Sep 2026

Based on: CHAOSS: Change Request Reviews (adjacent)

Reviewer Concentration (HHI)

proxy

0.256 Sep 2026

Based on: project-specific (no established CHAOSS/literature equivalent)

PR Review Engagement (Reviewers/PR)

proxy

1.3 May 2026 backfill pending

Based on: CHAOSS: Change Request Reviews (adjacent)

Contributor pipeline

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).

Tenure survival

Cohort size (n=15) 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	15	15	100.0%
6	13	13	100.0%
12	7	7	100.0%
18	1	1	100.0%
24	1	0	0.0%

Funnel, pooled across the last 11 horizon-elapsed cohorts (Sep 2013 – Jun 2015, n=71)

Pooled rather than shown as a single cohort month: at this cohort size, one month's bars are noisy enough on their own to be misleading, and the 730-day observation horizon means only cohorts old enough to be fully resolved are included here (no "in flight" segment).

Contributor leaderboard

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.

Commits

#	Contributor	Organization	Count
1	absurdfarce	IBM	14	Report an issue
2	Bret McGuire	unknown	3	Report an issue
3	Brad Schoening	unknown	3	Report an issue
4	mck	unknown	2	Report an issue
5	ramikg	unknown	1	Report an issue
6	Daniel Bershatsky	unknown	1	Report an issue
7	Dev-iL	unknown	1	Report an issue
8	brettabamonte	unknown	1	Report an issue
9	Brad Schoening	unknown	1	Report an issue
10	Hannes Järrendal	unknown	1	Report an issue
11	Jarek Potiuk	unknown	1	Report an issue
12	Thomas Kowalski	unknown	1	Report an issue
13	Luke Ratcliffe	unknown	1	Report an issue

Reviews

#	Contributor	Organization	Count
1	Bret McGuire	unknown	19	Report an issue
2	Brad Schoening	unknown	11	Report an issue
3	Brad Schoening reference: https://github.com/apache/cassandra-python-driver/pull/1279	unknown	1	Report an issue
4	Bret McGuire reference: https://github.com/apache/cassandra-python-driver/pull/1261	unknown	1	Report an issue
5	Brad Schoening reference: https://github.com/apache/cassandra-python-driver/pull/1287	unknown	1	Report an issue
6	Brad Schoening reference: https://github.com/apache/cassandra-python-driver/pull/1262	unknown	1	Report an issue
7	Andy Tolbert	unknown	1	Report an issue
8	Brad Schoening reference: https://github.com/apache/cassandra-python-driver/pull/1282	unknown	1	Report an issue
9	Brad Schoening reference: https://github.com/apache/cassandra-python-driver/pull/1264	unknown	1	Report an issue
10	Brad Schoening reference: https://github.com/apache/cassandra-python-driver/pull/1268	unknown	1	Report an issue
11	Bret McGuire reference: https://github.com/apache/cassandra-python-driver/pull/1297	unknown	1	Report an issue
12	Brad Schoening reference: https://github.com/apache/cassandra-python-driver/pull/1298	unknown	1	Report an issue
13	Brad Schoening reference: https://github.com/apache/cassandra-python-driver/pull/1296	unknown	1	Report an issue
14	Brad Schoening reference: https://github.com/apache/cassandra-python-driver/pull/1270	unknown	1	Report an issue
15	Bret McGuire reference: https://github.com/apache/cassandra-python-driver/pull/1263	unknown	1	Report an issue
16	Bret McGuire reference: https://github.com/apache/cassandra-python-driver/pull/1300	unknown	1	Report an issue

JIRA issues resolved

#	Contributor	Organization	Count
1	absurdfarce	unknown	11	Report an issue
2	bschoeni	unknown	1	Report an issue
3	brettabamonte	unknown	1	Report an issue
4	rishabhsaraswat	unknown	1	Report an issue

Organizational participation CHAOSS practitioner guide

Elephant Factor insufficient data
Organizational Concentration (HHI) insufficient data
Single-Organization Share insufficient data
Unknown-Affiliation Rate 54.8% Sep 2026 · n=31

Organizational Diversity

Elephant Factor

experimental

insufficient data

Based on: CHAOSS: Elephant Factor, CHAOSS wg-risk: Elephant Factor

Organizational Concentration (HHI)

established

insufficient data

Based on: CHAOSS: Organizational Diversity

Single-Organization Share

established

insufficient data

Based on: CHAOSS: Organizational Diversity

Unknown-Affiliation Rate

established

54.8% Sep 2026

Based on: project-specific (no established CHAOSS/literature equivalent)

Leadership CHAOSS practitioner guide

PMC Joins per Quarter shared — see Apache Cassandra

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 →

Releases CHAOSS: Release Frequency

Release Frequency 3 Sep 2026 · n=3
Days Between Releases (median) 122.5 days Sep 2026 · n=3
Time Since Last Release 120.0 days Oct 2026 · n=1

Release Cadence

Release Frequency

established

3 Sep 2026

Based on: CHAOSS: Release Frequency

Release Interval Regularity (CoV)

proxy

0.468 Sep 2026

Based on: project-specific (no established CHAOSS/literature equivalent)

Time Since Last Release

established

120.0 days Oct 2026

Based on: project-specific (no established CHAOSS/literature equivalent)

Days Between Releases (median)

proxy

122.5 days Sep 2026

Based on: CHAOSS: Release Frequency

Release lines, CI and blockers → /releases/

Conversation patterns

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 →