vavr-io/vavr

vʌvr (formerly called Javaslang) is a non-commercial, non-profit object-functional library that runs with Java 8+. It aims to reduce the lines of code and increase code quality.

6,157
Stars
over 12 years
Age
0
Published reviews
0
Questions

Reliability breakdown

What drives the reliability score

Component scores measured daily from GitHub activity (2026-02-26).

Continuity30% of headline58

Activity on 0 of 44 tracked days in the last 90 and 0 of 29 in the last 30.

Closure30% of headline94

Merged 0 of 0 PRs opened and closed 0 of 0 issues opened over the last 90 tracked days — PR flow carries 55% of this component, issue flow 45%.

Shipping20% of headline0

0 releases in the last 180 days, 0 in the last 90 and 0 in the last 30 — a steady cadence scores highest.

Liveness10% of headline100

Last push 5 days ago — freshness decays as pushes age (roughly halves every 83 days without a push).

Support burden10% of headline75

77 open issues against 6,157 stars — about 13 open issues per 1,000 stars. Lighter backlogs score higher.

Adoption confidence65

Modeled — how confidently teams are adopting this repo. Stargazers

Maintenance quality73

Modeled from PR/issue responsiveness and upkeep signals. Activity pulse

Risk score18

Modeled — lower is better; adoption and continuity risk. Repository

Stays active (30d)48%

Modeled chance the repo stays active over 30 days. Activity pulse

Stays active (90d)51%

Modeled chance the repo stays active over 90 days. Activity pulse

Release rhythm (180d)0

Regularity of releases over the last 180 days. Releases

Maintainer bus risk (90d)49%

Modeled — lower is better; concentration of commits in few maintainers. Contributors graph

Measured history

Project metrics

Weekly GitHub totals with 30, 90, and 180 day views.

Issues opened

Feb 22, 2026

Current1

Previous0

Weekly total

110
Full metrics details

GitHub API observation. Historical values render only when the source provides a real observation for that day.

36 observed daily rows. Missing days are not fabricated.

DateValue

Issues closed

Feb 22, 2026

Current2

Previous0

Weekly total

210
Full metrics details

GitHub Search issue totals queried for exact UTC days; rolling values are sums of proven daily counts.

36 observed daily rows. Missing days are not fabricated.

DateValue

Pull requests opened

Feb 22, 2026

Current5

Previous5

Weekly total

950
Full metrics details

GitHub API observation. Historical values render only when the source provides a real observation for that day.

36 observed daily rows. Missing days are not fabricated.

DateValue

Pull requests closed

Feb 22, 2026

Current3

Previous6

Weekly total

1050
Full metrics details

GitHub Search pull-request totals queried for exact UTC days; rolling values are sums of proven daily counts.

36 observed daily rows. Missing days are not fabricated.

DateValue

Pull requests merged

Feb 22, 2026

Current3

Previous5

Weekly total

950
Full metrics details

GitHub API observation. Historical values render only when the source provides a real observation for that day.

36 observed daily rows. Missing days are not fabricated.

DateValue

Issue close ratio (daily)

Feb 21, 2026

Current0.00

Previous0.00

Daily ratio — a gap means nothing was opened that day

How this works: each day's value is issues closed that day ÷ issues opened that day. Days when nothing was opened render as gaps — never a rolling average or a made-up zero. Values above 1 mean the project closed more issues than arrived that day.

1.000.500.00
Full metrics details

GitHub Search issue totals queried for exact UTC days; rolling values are sums of proven daily counts.

2 observed daily rows. Missing days are not fabricated.

Per-day formula: issues closed that day ÷ issues opened that day; blank when nothing was opened (a gap, not a zero).

DateIssues openedIssues closedStored score

Pull request close ratio (daily)

Feb 23, 2026

Current1.00

Previous0.50

Daily ratio — a gap means nothing was opened that day

How this works: each day's value is pull requests closed that day ÷ pull requests opened that day. Days when nothing was opened render as gaps — never a rolling average or a made-up zero. Values above 1 mean the project closed more pull requests than arrived that day.

2.001.000.00
Full metrics details

GitHub Search pull-request totals queried for exact UTC days; rolling values are sums of proven daily counts.

15 observed daily rows. Missing days are not fabricated.

Per-day formula: pull requests closed that day ÷ pull requests opened that day; blank when nothing was opened (a gap, not a zero).

DatePRs openedPRs closedStored score

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Project Q&A

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