Apache Cassandra C/C++ Driver · Project Health

Apache Cassandra C/C++ Driver

Automated, reproducible metrics for Apache Cassandra C/C++ Driver.

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 0.0% Oct 2026 · n=16
  • Open PR backlog 16 Sep 2026 · n=16
  • Median JIRA Resolution Latency insufficient data

Responsiveness

Median JIRA Resolution Latency (12m cohort)

established

insufficient data

Based on: CHAOSS: Issue Resolution Duration

JSON · CSV

PR Time to Close

proxy

799.4 days Sep 2025 backfill pending

Based on: CHAOSS: Change Requests (adjacent)

JSON · CSV

Change Request Closure Ratio — GitHub PR

proxy

0.333 Sep 2026

Based on: CHAOSS: Change Request Closure Ratio

JSON · CSV

Change Request Closure Ratio — JIRA Patch Submissions

established

insufficient data

Based on: CHAOSS: Change Request Closure Ratio

JSON · CSV

Issue Closure Ratio — GitHub Issues

proxy

n/a

insufficient data

Based on: CHAOSS: Issues Closed (adapted)

JSON · CSV

Reviewer Capacity

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.

Review responsiveness isn't published yet -- it appears once the Patch-Available changelog backfill has collected enough JIRA history for this project.

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 2 44% (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 3 Sep 2026 · n=3
  • New Contributors 2 Sep 2026 · n=2
  • Contributor Dependency (N for 50%) 2 Sep 2026 · n=8
  • Unique Reviewers 4 Sep 2026 · n=4

Contributor Sustainability

Active Contributors

established

3 Sep 2026

Based on: CHAOSS: Contributors

JSON · CSV

New Contributors

established

2 Sep 2026

Based on: CHAOSS: New Contributors

JSON · CSV

First → Second Contribution Conversion

proxy

80.0% Jun 2014 backfill pending

Based on: CHAOSS: Conversion Rate

JSON · CSV

Contributor Churn Rate

proxy

83.3% Aug 2024 backfill pending

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

JSON · CSV

Sustained Contributors

established

1 Sep 2026

Based on: CHAOSS: Contributors (adjacent)

JSON · CSV

Contributor Dependency (N for 50%)

established

2 Sep 2026

Based on: CHAOSS: Contributor Absence Factor

JSON · CSV

Contributor Concentration (HHI)

established

0.254 Sep 2026

Based on: DOJ/FTC: Herfindahl-Hirschman Index

JSON · CSV

Reviewer Capacity

Reviewer Concentration (HHI)

proxy

0.329 Sep 2026

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

JSON · CSV

PR Review Engagement (Reviewers/PR)

proxy

1.0 Jul 2023 backfill pending

Based on: CHAOSS: Change Request Reviews (adjacent)

JSON · CSV

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=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 5 5 100.0%
6 4 4 100.0%
12 2 2 100.0%
18 0 0 insufficient data
24 0 0 insufficient data

Funnel, latest horizon-elapsed cohort (Jun 2014, n=5)

low confidence (n < 30)

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.

Reviews

# Contributor Organization Count
1 Bret McGuire unknown 9 Report an issue
2 Yifan Cai unknown 3 Report an issue
3 Yifan Cai reference: https://github.com/apache/cassandra-cpp-driver/pull/591 unknown 1 Report an issue
4 Yifan Cai reference: https://github.com/apache/cassandra-cpp-driver/pull/594 unknown 1 Report an issue
5 Yifan Cai reference: https://github.com/apache/cassandra-cpp-driver/pull/581 unknown 1 Report an issue
6 Yifan Cai reference: https://github.com/apache/cassandra-cpp-driver/pull/590 unknown 1 Report an issue
7 Yifan Cai reference: https://github.com/apache/cassandra-cpp-driver/pull/580 unknown 1 Report an issue

JIRA issues resolved

# Contributor Organization Count
1 absurdfarce unknown 3 Report an issue

JSON · CSV

Organizational participation CHAOSS practitioner guide
  • Elephant Factor insufficient data
  • Organizational Concentration (HHI) insufficient data
  • Single-Organization Share insufficient data
  • Unknown-Affiliation Rate 53.8% Sep 2026 · n=13

Organizational Diversity

Organizational Concentration (HHI)

established

insufficient data

Based on: CHAOSS: Organizational Diversity

JSON · CSV

Single-Organization Share

established

insufficient data

Based on: CHAOSS: Organizational Diversity

JSON · CSV

Unknown-Affiliation Rate

established

53.8% Sep 2026

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

JSON · CSV

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 0 Sep 2026 · n=0
  • Days Between Releases (median) 344.0 days Nov 2023 · n=3
  • Time Since Last Release 1091.0 days Oct 2026 · n=1

Release Cadence

Release Frequency

established

0 Sep 2026

Based on: CHAOSS: Release Frequency

JSON · CSV

Release Interval Regularity (CoV)

proxy

1.089 Nov 2023 backfill pending

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

JSON · CSV

Time Since Last Release

established

1091.0 days Oct 2026

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

JSON · CSV

Days Between Releases (median)

proxy

344.0 days Nov 2023 backfill pending

Based on: CHAOSS: Release Frequency

JSON · CSV

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 →