PRcrastinate

Analyze GitHub Pull Request review latency metrics

---

A Ruby script to analyze GitHub Pull Request review latency metrics and export the data to CSV files for analysis in Excel or other tools.

Quickstart

# Get a GitHub token from https://github.com/settings/tokens (needs 'repo' scope)
export GITHUB_TOKEN=ghp_xxxxxxxxxxxx

# Run the analysis (analyzes all merged PRs since 2008-01-01)
./run myorg/myrepo

# Or specify a start date (analyzes from August 1st until now)
./run myorg/myrepo 2025-08-01

# Or with a specific date range
./run myorg/myrepo 2025-11-01 2025-11-30

This will generate two CSV files: pr_first_review.csv and pr_rereview_cycles.csv

Overview

PRcrastinate helps you understand how long it takes for PRs to get reviewed in your repository by tracking:

• Time from PR creation to first review
• Time from review request to first review
• Time from last commit to first review
• Re-review cycles after changes are requested

Prerequisites

• Docker
• A GitHub Personal Access Token

Getting a GitHub Token

1. Go to GitHub Settings: https://github.com/settings/tokens

2. Click "Generate new token" → "Generate new token (classic)"

3. Give your token a descriptive name (e.g., "PR Review Latency Analysis")

4. Set an expiration date (recommended: 90 days or custom)

5. Select the following scopes:

   • repo (Full control of private repositories)
     • This includes repo:status, repo_deployment, public_repo, repo:invite, and security_events
   • Alternatively, if analyzing only public repositories, you can use just:
     • public_repo (Access public repositories)

6. Click "Generate token"

7. Copy the token immediately - you won't be able to see it again!

Required Token Scopes

• For private repositories: repo scope
• For public repositories only: public_repo scope

The script needs read access to pull requests, reviews, and timeline events.

Usage

The ./run script runs the analysis in a Docker container, so you don't need Ruby installed locally.

Basic Usage

GITHUB_TOKEN=your_token_here ./run owner/repo

With Date Range

GITHUB_TOKEN=your_token_here ./run owner/repo YYYY-MM-DD
GITHUB_TOKEN=your_token_here ./run owner/repo YYYY-MM-DD YYYY-MM-DD

Arguments

1. Repository (required): GitHub repository in owner/name format (e.g., facebook/react)
2. SINCE date (optional): Start date for analysis in YYYY-MM-DD format (defaults to 2008-01-01)
3. UNTIL date (optional): End date for analysis in YYYY-MM-DD format (defaults to current time)

The script analyzes PRs that were merged between the SINCE and UNTIL dates.

Setting the Token

You can set the GITHUB_TOKEN environment variable in several ways:

Option 1: Inline (recommended for one-time use)

GITHUB_TOKEN=ghp_xxxxxxxxxxxx ./run owner/repo 2025-08-01

Option 2: Export in your shell session

export GITHUB_TOKEN=ghp_xxxxxxxxxxxx
./run owner/repo 2025-08-01

Option 3: In your shell profile (for repeated use)

Add to ~/.bashrc, ~/.zshrc, or equivalent:

export GITHUB_TOKEN=ghp_xxxxxxxxxxxx

Then reload your shell or run source ~/.bashrc

⚠️ Security Note: Never commit your token to version control. Consider using a .env file (and add it to .gitignore) or a secrets manager.

Examples

Analyze all merged PRs (from 2008-01-01 until now):

GITHUB_TOKEN=ghp_xxxxxxxxxxxx ./run myorg/myrepo

Analyze PRs merged from August 1st until now:

GITHUB_TOKEN=ghp_xxxxxxxxxxxx ./run myorg/myrepo 2025-08-01

Analyze PRs merged in November 2025:

GITHUB_TOKEN=ghp_xxxxxxxxxxxx ./run myorg/myrepo 2025-11-01 2025-11-30

Running without Docker (if you have Ruby installed):

GITHUB_TOKEN=ghp_xxxxxxxxxxxx ruby lib/prcrastinate.rb myorg/myrepo
GITHUB_TOKEN=ghp_xxxxxxxxxxxx ruby lib/prcrastinate.rb myorg/myrepo 2025-08-01

Output

The script generates two CSV files:

pr_first_review.csv

One row per PR with columns:

• repo: Repository name
• pr_number: PR number
• pr_url: Link to the PR
• pr_title: PR title
• pr_author: GitHub username of PR author
• created_at: When the PR was created
• merged_at: When the PR was merged
• is_draft: Whether the PR was a draft
• first_review_at: When the first review was submitted
• created_to_first_review_seconds: Latency from creation to first review
• earliest_review_requested_at: When the first review was requested
• review_requested_to_first_review_seconds: Latency from review request to first review
• last_commit_before_first_review_at: Last commit before the first review
• last_commit_to_first_review_seconds: Latency from last commit to first review

pr_rereview_cycles.csv

One row per re-review cycle (after CHANGES_REQUESTED) with columns:

• repo: Repository name
• pr_number: PR number
• pr_url: Link to the PR
• cycle_index: Which re-review cycle this is (1, 2, 3...)
• cycle_start_at: When the cycle started (first commit after changes requested)
• cycle_end_at: When the cycle ended (next review submission)
• cycle_seconds: Duration of the re-review cycle
• cycle_trigger: What triggered the cycle (e.g., AUTHOR_COMMIT_AFTER_CR)
• end_review_state: State of the review that ended the cycle
• end_reviewer: Who submitted the review that ended the cycle

Analyzing the Data

The CSV files can be imported into Excel, Google Sheets, or any data analysis tool.

Suggested analyses:

• Create pivot tables grouping by week or month
• Calculate mean, median, and p90 (90th percentile) review latencies
• Filter out draft periods or bot activity
• Identify trends over time
• Compare latencies across different time periods

Troubleshooting

"Missing GITHUB_TOKEN env var"

• Make sure you've set the GITHUB_TOKEN environment variable

"HTTP error 401" or "Bad credentials"

• Your token is invalid or expired - generate a new one

"HTTP error 403" or "Resource not accessible"

• Your token doesn't have the required scopes
• For private repos, ensure the repo scope is enabled
• The repository might not exist or you don't have access

"GraphQL errors"

• Check that the repository name is in the correct format: owner/name
• Verify the dates are in YYYY-MM-DD format