Make R-models compatible with Chap

This page covers how to set up the environment for R-based models using renv.

Environment options

renv environment (for R models)

Use renv_env to specify an renv.lock file for R models that use renv for dependency management:

renv_env: renv.lock

When Chap runs your model, it will automatically:

1. Look for the renv.lock file in your model directory
2. Run renv::restore(prompt = FALSE) to install all required R packages
3. Execute your R commands with the restored environment

Your model directory should contain:

• renv.lock - The lockfile specifying exact package versions (generated by renv::snapshot())
• renv/ directory - Contains renv activation scripts
• .Rprofile - Auto-activates renv when R starts (typically contains source("renv/activate.R"))

Setting up renv for your R model

1. Initialize renv in your R project:

   renv::init()
   

2. Install your required packages:

   renv::install("dplyr")
   renv::install("argparser")
   # ... other packages
   

3. Create the lockfile:

   renv::snapshot()
   

This creates renv.lock with exact versions of all dependencies, ensuring reproducible environments.

See the minimalist R model example for a complete working example.

Next steps

• For prediction length constraints and configurable model parameters, see Additional Configuration