#rpackageadvent2025 — Public Fediverse posts

We Made It! 🎉

25 days. Complete modern R package development workflow. From usethis automation to CRAN submission. You have everything you need!

Your Next Steps:
✨ Apply these tools to your packages
📚 Bookmark for reference
🤝 Share knowledge with community
🚀 Build amazing R packages

Thank you for following #RPackageAdvent2025! Now go make the R ecosystem better! 🎄📦
Keep Learning: https://r-pkgs.org | https://usethis.r-lib.org

#rstats #CRAN #RPackageAdvent2025 #ThatsAWrap

Day 25: CRAN Submission Checklist and https://cran-comments.md

Final steps for successful CRAN submission.

Pre-submission checklist:

- devtools::check() passes with 0 errors, warnings, notes
- Test on multiple platforms (rhub, GitHub Actions)
- Update https://NEWS.md and version number
- Check reverse dependencies
- Spell check documentation

#rstats #RPackageAdvent2025

Day 24: rlang - Tidy Evaluation in Packages

Handle user expressions safely in package functions.

Basic tidy evaluation:
my_summarise <- function(data, ...) {
data |>
dplyr::summarise(...)
}

# Embrace operator
my_mutate <- function(data, col, value) {
data |>
dplyr::mutate({{ col }} := value)
}

Pro Tip: Use {{ }} (embrace) for single arguments, ... for multiple arguments.
Resources: https://rlang.r-lib.org

#rstats #RPackageAdvent2025

Day 23: cli - Beautiful Command Line Interfaces

Create user-friendly messages and progress indicators.

Enhanced messages:
cli::cli_alert_success("Package built successfully!")
cli::cli_alert_warning("Missing documentation for {.fn my_function}")
cli::cli_abort("Invalid input: {.val {invalid_value}}")

Pro Tip: Use semantic markup like {.fn function_name} and {.val value} for consistent formatting.
Resources: cli.r-lib.org

#RpackageAdvent2025 #rstats

Day 22: S3, S4, and S7 Object Systems

Create robust object-oriented interfaces with R's object systems.

Pro Tip: Use S3 for simple classes, S4 for complex validation, S7 for modern OOP.
Resources: https://rconsortium.github.io/S7

#rstats #RPackageAdvent2025

Day 21: rhub - Multi-Platform Testing

Test your package on multiple platforms before CRAN submission.

Resources: https://r-hub.github.io/rhub/

#rstats #RPackageAdvent2025

1/ CRAN Tests Everywhere: Windows, macOS, Linux, multiple flavors. Your package must work on all. rhub lets you test before submission.

2/ Run CRAN Checks:
rhub::check_for_cran()

Tests on Debian, Windows, Fedora. Same platforms CRAN uses. Catch platform-specific issues early.

Day 20: Performance Testing with bench

Profile and benchmark your package functions.

Basic benchmarking:

results <- bench::mark(
old_approach = old_function(data),
new_approach = new_function(data),
check = FALSE, # Skip result equality check
iterations = 100
)
plot(results)

Pro Tip: Include benchmarks in your test suite to catch performance regressions.
Resources: https://bench.r-lib.org/

#rstats #RPackageAdvent2025

Day 19: goodpractice - Package Health Checks

Get comprehensive feedback on package quality.

Usage:
goodpractice::gp()

Checks include:
⬩ Function length and complexity
⬩ Namespace usage
⬩ DESCRIPTION completeness
⬩ Code coverage
⬩ R CMD check results

Pro Tip: Run gp() before CRAN submission to catch common issues early.
Resources: github.com/mangothecat/goodpractice

#rstats #RPackageAdvent2025

Day 18: Use linters!

Maintain consistent, readable code style automatically.

Setup:
# .lintr file in project root
linters: linters_with_defaults(
line_length_linter(120),
commented_code_linter = NULL
)

Usage:
lintr::lint_package()
styler::style_pkg()

Pro Tip: Add both to pre-commit hooks for automatic code formatting.
Resources: https://lintr.r-lib.org/

#rstats #RPackageAdvent2025

Day 17: vcr - Recording API Calls for Tests

Record real API responses for reliable, fast tests without hitting live APIs.

Setup:
library(vcr)
vcr_configure(dir = "tests/fixtures/vcr_cassettes")

Pro Tip: Commit cassette files to git for reproducible tests across environments.
Resources: docs.ropensci.org/vcr

#rstats #RPackageAdvent2025

Day 16: Testing with Mocks using testthat
Test functions that depend on external resources using testthat's built-in mocking.

Pro Tip: Use local_mocked_bindings() to mock functions within the test scope only.
Resources: testthat.r-lib.org

#rstats #RPackageAdvent2025

Day 15: Snapshot Testing with testthat

Test complex outputs that are hard to specify exactly.

Text snapshots:
test_that("error messages are informative", {
expect_snapshot(my_function(bad_input), error = TRUE)
})

Pro Tip: Review snapshot changes carefully - they capture everything, including whitespace and formatting.

#rstats #RPackageAdvent2025

Day 14: testthat 3rd Edition Features
Modern testing with the latest testthat features.

Setup:
usethis::use_testthat(3)

New features:

# Snapshot tests
test_that("plot output is stable", {
p <- my_plot(data)
vdiffr::expect_doppelganger("basic-plot", p)
})

Helper functions in tests/testthat/helper.R

Pro Tip: Use test_that() with descriptive names that explain what should happen.
Resources: https://testthat.r-lib.org

#rstats #RPackageAdvent2025

Day 13: covr - Test Coverage Reporting

Track how much of your code is tested.
use #nocov for code you don't want to cover (like basic R functions etc)

Basic usage:
covr::package_coverage()
covr::report()

Integration with CI:
usethis::use_github_action("test-coverage")
usethis::use_coverage() # Adds codecov badge

Pro Tip: Aim for >80% coverage, but focus on testing critical functions thoroughly rather than chasing 100%.
Resources: https://covr.r-lib.org

#rstats #RPackageAdvent2025

Day 12: README.Rmd Automation

Create dynamic READMEs that stay up-to-date with your code.

Setup:
usethis::use_readme_rmd()

Include these sections:

󠁯•󠁏󠁏 Installation instructions
󠁯•󠁏󠁏 Basic usage example
󠁯•󠁏󠁏 Lifecycle badges
󠁯•󠁏󠁏 Build status badges

Keep it fresh:

# Add to .github/workflows/
- name: Render README
run: Rscript -e 'rmarkdown::render("README.Rmd")'

#rstats #RPackageAdvent2025

Day 11: https://NEWS.md and Semantic Versioning
Keep users informed about package changes.

Create https://NEWS.md:
usethis::use_news_md()

Structure:
# mypackage 1.2.0

## New features
* Added `new_function()` for advanced analysis (#15)

## Bug fixes
* Fixed issue with missing values in `existing_function()` (#12)

Pro Tip: Follow semantic versioning: MAJOR.MINOR.PATCH for breaking.feature.bugfix changes.

#rstats #RPackageAdvent2025

Day 10: lifecycle - Managing Function Deprecation

Communicate changes to users gracefully with lifecycle badges.

Setup:
usethis::use_lifecycle()

#' @lifecycle experimental
new_function <- function() {
# function body
}

Pro Tip: Use lifecycle stages: experimental → stable → superseded → deprecated.
Resources: https://lifecycle.r-lib.org
#rstats #RPackageAdvent2025

Day 9: Vignettes with knitr and rmarkdown

Create comprehensive tutorials and examples for your package.

Add a vignette:
usethis::use_vignette("getting-started")

Vignette best practices:

● Start with a clear problem statement
● Show realistic examples
● Keep computational time under 5 minutes
● Use pre-computed results for heavy computations

Pro Tip: Use knitr::opts_chunk$set(collapse = TRUE, comment = "#>") for clean output.
#rstats #RPackageAdvent2025

Day 8: pkgdown Customization and Deployment

Transform your package documentation into a polished website.

Advanced customization:

# _pkgdown.yml
template:
params:
bootswatch: flatly

reference:
- title: "Data manipulation"
contents:
- starts_with("mutate")
- ends_with("_join")

Auto-deployment:
usethis::use_github_action("pkgdown")

Pro Tip: Group functions logically in the reference section for better navigation.
#rstats #RPackageAdvent2025

Day 7: roxygen2 Advanced Tags and Cross-References 📝

Master documentation with advanced roxygen2 features, with markdown-style writing! 🎯

💡 Pro Tip: Use @inheritDotParams to inherit ... parameter documentation.
📚 Resources: https://roxygen2.r-lib.org

#rstats #roxygen2 #Documentation #RPackageAdvent2025

The Bottom Line: Manually editing DESCRIPTION = typos, wrong formatting, forgotten versions. usethis = automatic, correct, sorted. Let the tool handle the details so you focus on code.
Tomorrow: Advanced roxygen2 for better documentation! 📝

Resources: https://usethis.r-lib.org
#rstats #usethis #Dependencies #RPackageAdvent2025

Day 6/25: Adding dependencies to your #rstats package 🧵

#rstats #RPackageAdvent2025

The Manual DESCRIPTION Problem: You need to add dplyr to your package. Open DESCRIPTION, find Imports, type "dplyr," hope you didn't typo it, wonder if you need a version constraint, forget to sort alphabetically. Then your package fails R CMD check.

usethis Does It Right:
usethis::use_package("dplyr")

Adds to Imports section, alphabetically sorted, with correct formatting. One command, zero mistakes.

Day 5: Package Structure with pkgdown Site Generation 🌐
Create beautiful documentation websites for your packages! ✨

Setup: 🔧

usethis::use_pkgdown()
pkgdown::build_site()

💡 Pro Tip: Use usethis::use_pkgdown_github_pages() for automatic deployment.
📚 Resources: https://pkgdown.r-lib.org

#rstats #pkgdown #Documentation #RPackageAdvent2025 📖

Day 4: .Rbuildignore and .gitignore Best Practices 📁

Control what gets included in your package build and git repository! 🎯

💡 Pro Tip: Use usethis::use_build_ignore() to add entries programmatically.
#rstats #BestPractices #Git #RPackageAdvent2025 🗃️

Day 3: GitHub Actions with r-lib/actions - CI/CD Setup 🚀

Automate your package testing across multiple platforms and R versions! 🔄
Quick setup: ⚡

💡 Pro Tip: The standard check runs on Windows, macOS, and Ubuntu with
multiple R versions.

📚 Resources: https://github.com/r-lib/actions

#GitHubActions #rstats #CI #RPackageAdvent2025

Day 2: devtools - Essential Development Workflow 🔧

The devtools package streamlines your package development workflow with key functions! ⚡

💡 Pro Tip: Use Ctrl/Cmd + Shift + L in RStudio to quickly run load_all().

📚 Resources: https://devtools.r-lib.org

#RPackageDev #RStats #devtools #RPackageAdvent2025
🛠️

Day 1: usethis - Project Setup Automation 🎯

The usethis package is your best friend for automating repetitive package development tasks! 🤖

💡 Pro Tip: Set up your global options once with usethis::edit_r_profile() to add your name, email, and preferred license.

📚 Resources: https://usethis.r-lib.org
#RPackageDev #RStats #usethis #RPackageAdvent2025 📦

How to Follow Along:

I'll post daily starting Dec 1st
Each post includes practical code examples
Follow the #RPackageAdvent2025 hashtag
Comment with your questions - I'll answer!
Share your favorite tips with the community

Why I'm Doing This: I've developed multiple R packages and learned these lessons the hard way. My goal is to save you time, frustration, and help you build better packages that users love.
Ready to level up your R package game? See you December 1st! 🚀

🎄 ANNOUNCEMENT: R Package Development Advent Calendar 2025! 🎄

Starting December 1st, I'm launching a 25-day journey through modern R package development. But this isn't just another tips series - here's why you should follow along 🧵

The Problem: R package development can feel overwhelming. Between documentation, testing, CI/CD, and CRAN submission, there are dozens of tools to learn.

#rstats #RPackageAdvent2025