How to add packages to a .bib file from within a .qmd file

citations.qmd

---
format: html
bibliography: [references.bib, packages.bib]
---

<!-- The `references.bib` files is for other, non-package, references. -->

```{r setup}
#| include: false

# This function takes package names as characters
# - checks they're installed
# - saves them for later
# - prints them out as @R-<package names>
citepkg <- function(...) {
  pkg <- c(...)
  stopifnot(insight::check_if_installed(pkg, stop = TRUE, prompt = FALSE))
  
  pkgs2cite <- getOption("pkgs2cite", default = NULL)
  options(pkgs2cite = c(pkgs2cite, pkg))
  
  paste0(paste0("@R-", pkg), collapse = "; ")
}
```

All analyses were carried out in R [`r citepkg("base")`] 
using some really amazing packages [`r citepkg("tidyverse", "ggplot2")`].

<!-- See comment below for how this works out. -->

# References

<!-- Then right before the references add this chunk - and that's it! -->

```{r write-bib}
#| include: false
#| echo: false
pkgs2cite <- getOption("pkgs2cite", default = NULL)
pkgs2cite <- unique(c("base", pkgs2cite))
knitr::write_bib(pkgs2cite, file = "packages.bib")
```

::: {#refs}
:::

This is how those citations are rendered in the .md file:

All analyses were carried out in R [@R-base] 
using some really amazing packages [@R-tidyverse; @R-ggplot2].

Which results in: