diff --git a/DESCRIPTION b/DESCRIPTION
index 616ac5a..a41ed3a 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -22,9 +22,9 @@ Imports:
     utils,
     whisker,
     withr,
-    rextendr,
     here,
     cli,
+    stringi
 Suggests: 
     knitr,
     rmarkdown,
diff --git a/NAMESPACE b/NAMESPACE
index ef9e092..5dc950c 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -1,5 +1,14 @@
 # Generated by roxygen2: do not edit by hand
 
+S3method(format_toml,"NULL")
+S3method(format_toml,character)
+S3method(format_toml,data.frame)
+S3method(format_toml,default)
+S3method(format_toml,double)
+S3method(format_toml,integer)
+S3method(format_toml,list)
+S3method(format_toml,logical)
+S3method(format_toml,name)
 export(generate_nmm_config)
 export(get_slurm_jobs)
 export(get_slurm_partitions)
@@ -17,11 +26,23 @@ importFrom(fs,file_exists)
 importFrom(fs,is_absolute_path)
 importFrom(fs,path_abs)
 importFrom(glue,glue)
+importFrom(glue,glue_collapse)
 importFrom(jsonlite,fromJSON)
 importFrom(processx,run)
+importFrom(purrr,discard)
+importFrom(purrr,flatten_chr)
 importFrom(purrr,list_rbind)
 importFrom(purrr,map)
+importFrom(purrr,map2)
+importFrom(purrr,map2_chr)
+importFrom(purrr,map_if)
 importFrom(rlang,abort)
+importFrom(rlang,as_function)
+importFrom(rlang,dots_list)
+importFrom(rlang,is_atomic)
+importFrom(rlang,is_missing)
+importFrom(rlang,names2)
+importFrom(stringi,stri_replace_all_regex)
 importFrom(tibble,tibble)
 importFrom(utils,globalVariables)
 importFrom(utils,read.table)
diff --git a/R/nmm-config.R b/R/nmm-config.R
index c9b8377..d037267 100644
--- a/R/nmm-config.R
+++ b/R/nmm-config.R
@@ -62,15 +62,15 @@ generate_nmm_config <- function(
 
   if (length(alerter_opts) != 0) {
     if ("args" %in% names(alerter_opts)) {
-      write_file(rextendr::to_toml(
+      write_file(to_toml(
         toml,
         alerter = alerter_opts[names(alerter_opts) != "args"],
         alerter.args = alerter_opts$args),
         config_toml_path)
     } else {
-      write_file(rextendr::to_toml(toml, alerter = alerter_opts), config_toml_path)
+      write_file(to_toml(toml, alerter = alerter_opts), config_toml_path)
     }
   } else {
-    write_file(rextendr::to_toml(toml), config_toml_path)
+    write_file(to_toml(toml), config_toml_path)
   }
 }
diff --git a/R/slurmtools-package.R b/R/slurmtools-package.R
index 9c7be73..1044ae9 100644
--- a/R/slurmtools-package.R
+++ b/R/slurmtools-package.R
@@ -15,11 +15,24 @@
 #' @importFrom fs is_absolute_path
 #' @importFrom fs path_abs
 #' @importFrom glue glue
+#' @importFrom glue glue_collapse
 #' @importFrom jsonlite fromJSON
 #' @importFrom processx run
+#' @importFrom purrr discard
+#' @importFrom purrr flatten_chr
 #' @importFrom purrr list_rbind
 #' @importFrom purrr map
+#' @importFrom purrr map_if
+#' @importFrom purrr map2
+#' @importFrom purrr map2_chr
 #' @importFrom rlang abort
+#' @importFrom rlang as_function
+#' @importFrom rlang dots_list
+#' @importFrom rlang is_atomic
+#' @importFrom rlang is_missing
+#' @importFrom rlang map2_chr
+#' @importFrom rlang names2
+#' @importFrom stringi stri_replace_all_regex
 #' @importFrom tibble tibble
 #' @importFrom utils globalVariables
 #' @importFrom utils read.table
diff --git a/R/toml_serialization.R b/R/toml_serialization.R
new file mode 100644
index 0000000..4db5513
--- /dev/null
+++ b/R/toml_serialization.R
@@ -0,0 +1,308 @@
+# This is pulled from the rextendr package commit c698bf3
+# https://github.com/extendr/rextendr/blob/main/R/toml_serialization.R
+
+
+#' Convert R `list()` into toml-compatible format.
+#'
+#' [to_toml()] can be used to build `Cargo.toml`.
+#' The cargo manifest can be represented in terms of
+#' R objects, allowing limited validation and syntax verification.
+#' This function converts manifests written using R objects into
+#' toml representation, applying basic formatting,
+#' which is ideal for generating cargo
+#' manifests at runtime.
+#'
+#' @param ... A list from which toml is constructed.
+#'     Supports nesting and tidy evaluation.
+#' @param .str_as_literal Logical indicating whether to treat
+#'     strings as literal (single quotes no escapes) or
+#'     basic (escaping some sequences) ones. Default is `TRUE`.
+#' @param .format_int,.format_dbl Character scalar describing
+#'     number formatting. Compatible with `sprintf`.
+#' @return A character vector, each element corresponds to
+#'     one line of the resulting output.
+#' @examples
+#' # Produces [workspace] with no children
+#' to_toml(workspace = NULL)
+#'
+#' to_toml(patch.crates_io = list(`extendr-api` = list(git = "git-ref")))
+#'
+#' # Single-element arrays are distinguished from scalars
+#' # using explicitly set `dim`
+#' to_toml(lib = list(`crate-type` = array("cdylib", 1)))
+#' @noRd
+to_toml <- function(...,
+                    .str_as_literal = TRUE,
+                    .format_int = "%d",
+                    .format_dbl = "%g") {
+  args <- dots_list(
+    ...,
+    .preserve_empty = TRUE,
+    .ignore_empty = "none",
+    .homonyms = "error",
+    .check_assign = TRUE
+  )
+  names <- names2(args)
+
+  # We disallow unnamed top-level atomic arguments
+  invalid <- which(purrr::map2_lgl(names, args, ~ !nzchar(.x) && is.atomic(.y)))
+
+  # If such args found, display an error message
+  if (length(invalid) > 0) {
+    cli::cli_abort(
+      c(
+        get_toml_err_msg(),
+        "x" = "Unnamed arguments found at {cli::qty(length(invalid))} position{?s}: {invalid}.",
+        "i" = "All top-level values should be named."
+      ),
+      class = "rextendr_error"
+    )
+  }
+
+  tables <- map2_chr(names, args, function(nm, a) {
+    header <- make_header(nm, a)
+    body <- format_toml(
+      a,
+      .top_level = TRUE,
+      .tbl_name = ifelse(is.data.frame(a), nm, character(0)),
+      .str_as_literal = .str_as_literal,
+      .format_int = .format_int,
+      .format_dbl = .format_dbl
+    )
+    body <- glue_collapse(body, "\n")
+    if (!nzchar(body)) {
+      body <- NULL
+    }
+
+    # The values can be (1) header and body, (2) header only, or (3) body only.
+    # In the case of (2) and (3) the other element is of length 0, so we need to
+    # remove them by `c()` first, and then concatenate by "\n" if both exists
+    glue_collapse(c(header, body), "\n")
+  })
+  glue_collapse(tables, "\n\n")
+}
+
+make_header <- function(nm, arg) {
+  # For future support of array-of-table
+  # https://toml.io/en/v1.0.0-rc.3#array-of-tables
+  if (nzchar(nm) && !is.data.frame(arg)) {
+    as.character(glue("[{nm}]"))
+  } else {
+    character(0)
+  }
+}
+
+get_toml_err_msg <- function() "Object cannot be serialized."
+get_toml_missing_msg <- function() {
+  "Missing arument and `NULL` are only allowed at the top level."
+}
+
+simplify_row <- function(row) {
+  result <- map_if(
+    row,
+    ~ is.list(.x) && all(!nzchar(names2(.x))),
+    ~ .x[[1]],
+    .else = ~.x
+  )
+  discard(
+    result,
+    ~ is_na(.x) || is_null(unlist(.x))
+  )
+}
+
+
+format_toml <- function(x, ..., .top_level = FALSE) UseMethod("format_toml")
+
+#' @export
+format_toml.default <- function(x, ..., .top_level = FALSE) {
+  cli::cli_abort(c(
+    get_toml_err_msg(),
+    "x" = "{.code {class(x)}} cannot be converted to toml."
+  ), class = "rextendr_error")
+}
+
+#' @export
+format_toml.data.frame <- function(x,
+                                   ...,
+                                   .tbl_name,
+                                   .top_level = FALSE) {
+  rows <- nrow(x)
+  header <- glue("[[{.tbl_name}]]")
+  if (rows == 0L) {
+    return(as.character(header))
+  }
+  result <-
+    map(
+      seq_len(rows),
+      function(idx) {
+        item <- simplify_row(dplyr::slice(x, idx))
+        if (length(item) == 0L) {
+          result <- character(0)
+        } else {
+          result <- format_toml(
+            item,
+            ...,
+            .top_level = TRUE
+          )
+        }
+        if (!is_atomic(result)) {
+          result <- flatten_chr(result)
+        }
+
+        c(header, result)
+      }
+    )
+  flatten_chr(result)
+}
+
+# This handles missing args
+# `to_toml(workspace = )` results into
+# [workspace] with no children
+#' @export
+format_toml.name <- function(x, ..., .top_level = FALSE) {
+  if (isTRUE(.top_level)) {
+    if (is_missing(x)) {
+      return(character(0))
+    } else {
+      # This function errors and does not return
+      format_toml.default(x, ..., .top_level = .top_level)
+    }
+  } else {
+    if (is_missing(x)) {
+      cli::cli_abort(
+        c(get_toml_err_msg(), "x" = get_toml_missing_msg()),
+        class = "rextendr_error"
+      )
+    } else {
+      # This function errors and does not return
+      format_toml.default(x, ..., .top_level = .top_level)
+    }
+  }
+}
+
+# `NULL` is equivalent to missing arg
+#' @export
+format_toml.NULL <- function(x, ..., .top_level = FALSE) {
+  if (isTRUE(.top_level)) {
+    return(character(0))
+  } else {
+    cli::cli_abort(
+      c(get_toml_err_msg(), "x" = get_toml_missing_msg()),
+      class = "rextendr_error"
+    )
+  }
+}
+
+format_toml_atomic <- function(x,
+                               ...,
+                               .top_level = FALSE,
+                               .formatter) {
+  # Cache dimensions because slicing drops attributes
+  dims <- dim(x)
+  x <- x[!is.na(x)]
+  len <- length(x)
+
+  if (len == 0L) {
+    "[ ]"
+  } else {
+    formatter <- as_function(.formatter)
+    items <- glue_collapse(formatter(x, ...), ", ")
+    if (len > 1L || !is.null(dims)) {
+      items <- glue("[ {items} ]")
+    }
+    # Ensure type-stability
+    as.character(items)
+  }
+}
+
+# This should escape basic symbols
+escape_dbl_quotes <- function(x) {
+  stri_replace_all_regex(x, "([\"])", r"(\\$1)")
+}
+
+#' @export
+format_toml.character <- function(x,
+                                  ...,
+                                  .str_as_literal = TRUE,
+                                  .top_level = FALSE) {
+  if (isTRUE(.str_as_literal)) {
+    .formatter <- ~ glue("'{.x}'")
+  } else {
+    .formatter <- ~ glue("\"{escape_dbl_quotes(.x)}\"")
+  }
+  format_toml_atomic(
+    x,
+    ...,
+    .str_as_literal = .str_as_literal,
+    .top_level = FALSE,
+    .formatter = .formatter
+  )
+}
+
+#' @export
+format_toml.integer <- function(x,
+                                ...,
+                                .format_int = "%d",
+                                .top_level = FALSE) {
+  format_toml_atomic(
+    x,
+    ...,
+    .format_int = .format_int,
+    .top_level = FALSE,
+    .formatter = ~ sprintf(.format_int, .x)
+  )
+}
+
+#' @export
+format_toml.double <- function(x,
+                               ...,
+                               .format_dbl = "%g",
+                               .top_level = FALSE) {
+  format_toml_atomic(
+    x,
+    ...,
+    .format_dbl = .format_dbl,
+    .top_level = FALSE,
+    .formatter = ~ sprintf(.format_dbl, .x)
+  )
+}
+
+#' @export
+format_toml.logical <- function(x,
+                                ...,
+                                .top_level = FALSE) {
+  format_toml_atomic(
+    x,
+    ...,
+    .top_level = FALSE,
+    .formatter = ~ ifelse(.x, "true", "false")
+  )
+}
+
+#' @export
+format_toml.list <- function(x, ..., .top_level = FALSE) {
+  names <- names2(x)
+  invalid <- which(!nzchar(names))
+  if (length(invalid) > 0) {
+    cli::cli_abort(
+      c(
+        get_toml_err_msg(),
+        "x" = "Unnamed arguments found at position{?s}: {invalid}.",
+        "i" = "List values should have names."
+      ),
+      class = "rextendr_error"
+    )
+  }
+  result <- map2(names, x, function(nm, val) {
+    glue("{nm} = {format_toml(val, ..., .top_level = FALSE)}")
+  })
+
+  if (!.top_level) {
+    result <- glue("{{ {paste0(result, collapse = \", \")} }}")
+  }
+  if (!is_atomic(result)) {
+    result <- flatten_chr(result)
+  }
+  # Ensure type-stability
+  as.character(result)
+}