Compute the deadline of a GitHub Milestone based on corrected issue estimates.
- incurs a low-impact process on assignees
- puts estimates near all relevant details
- permits estimate revision as easily as providing the original estimate
- fosters single-source-of-truth for issue milestones and assignments
- adjusts the deadline when things are added, reopened, moved, or closed
- compensates for past estimate track-record
- does not increase the number of developer tools
An issue has an estimate if has a label such as:
2 days
14 hours
1 week
3 points
or more flexibly if any of its comments have a line of the format:
estimated 2 days
14hr estimate
eta 0.9 week per mrmanager
3 points
Comment estimates may be made by the assignee, other potential assignee(s), or both.
The Closed Issues Estimates (CIE) is the sum of estimates of closed issues, grouped by an assignee.
Available Time (AT) is a function that computes the assignee availability over a timespan, excluding their time off, holidays, or other jobs.
For each assignee, the Velocity (V) is the ratio:
V = CIE / AT(start..now)
A V of 100% means their estimates were accurate, whereas 200% means they took half as long as estimated.
Open Issues Estimate (OIE) is the sum of estimates of open issues, grouped by an assignee.
A Corrected Open Issues Estimate (COIE) is computed for each assignee by:
COIE = OIE * AT(now..COIE) / V
Issues with non-assignee estimates are potentially manually (re)assignable, or Sheddable Issues (SI).
The milestone's deadline is set to the last assignee's COIE.
The milestone's description is updated with an estimate report,
ordered by assignee's COIE (labeled done). For estimate
calibration, the OIE, AT(now..COIE), and V are revealed (labeled
estimate, avail., and velocity). For rebalancing, some SI IDs
are listed (labeled sheddable).
| assignee | done | estimate | avail. | velocity | sheddable |
|----------|--------:|---------:|-------:|---------:|-----------|
| @user1 | 10 days | 10 days | 88% | 110% | #239 |
| @user2 | 68 days | 138 days | 100% | 200% | #226 |
| @user3 | TBD | | | | |
which renders like:
| assignee | done | estimate | avail. | velocity | sheddable |
|---|---|---|---|---|---|
| @user1 | 10 days | 10 days | 88% | 110% | #239 |
| @user2 | 68 days | 138 days | 100% | 200% | #226 |
| @user3 | TBD |
If either CIE or AT(start..now) are 0, V is 100%. This serves estimating before commencing work.
If any open issue for the milestone does not have an estimate, or if the milestone has a prior open milestone without a deadline, the milestone deadline is not computable. The deadline is thus unset.
If the open issue is assigned but without an estimate, the assignee's
COIE is TBD. This calls out those who have not provided
estimates.
Closed issues without estimates are assumed to take 0 time, and thus their assignment is irrelevant. This encourages providing estimates, even retroactively.
Open issues without assignees but with comment estimates are deadline-optimally distributed among the commenters who provided estimates.
Open issues without assignees but with labeled estimates are deadline-optimally distributed among the discovered assignees.
The milestone description may also have lines specifying the following configuration options.
The scale of COIE and OIE, specified in the report header:
estimates (hours)
estimates (days)
estimates (weeks)
estimates (months)
estimates (points)
If absent, the scale is days.
AT baseline, specified in the milestone description:
user1: 7hours/day, 2days/week
user2: 10hr/day, 6d/wk
36hours/week
4pt/week
If absent:
8hours/day
40hours/week
22days/month
1point/week
AT exceptions, specified in the milestone description:
user1: vacation 2014-05-09 to 2014-05-12
user2: unavailable 2014-05-14
holiday 2014-05-22
Assignee's start on the milestone, specified in the milestone description:
user2: started 2014-05-01
started 2014-04-01
If absent, it's the earliest of the assignee's closed issues minus estimate. If none of their issues are closed, it defaults to now.
Prior milestones, specified in the milestone description:
after milestone name
after milestone_id
The earliest start date for each assignee in this milestone is the latest COIE of prior milestone.
Non-linear V, if longer estimates are habitually less accurate than shorter.
Limit unassigned issues to a subset of potential assignees.
End time or total units of time available.