diff --git a/DESCRIPTION b/DESCRIPTION
index d668e342..e533fc9f 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -55,4 +55,4 @@ Config/Needs/cpp11/cpp_register:
     vctrs
 Encoding: UTF-8
 Roxygen: list(markdown = TRUE)
-RoxygenNote: 7.2.3
+RoxygenNote: 7.2.2
diff --git a/R/register.R b/R/register.R
index 3ea10d52..5e41fc04 100644
--- a/R/register.R
+++ b/R/register.R
@@ -67,12 +67,11 @@ cpp_register <- function(path = ".", quiet = !is_interactive(), extension = c(".
 
   dir.create(dirname(r_path), recursive = TRUE, showWarnings = FALSE)
 
-  brio::write_lines(path = r_path, glue::glue('
+  brio::write_lines(path = r_path, glue::glue("
       # Generated by cpp11: do not edit by hand
 
       {r_functions}
-      '
-  ))
+      "))
   if (!quiet) {
     cli::cli_alert_success("generated file {.file {basename(r_path)}}")
   }
@@ -85,11 +84,11 @@ cpp_register <- function(path = ".", quiet = !is_interactive(), extension = c(".
     n_args = viapply(funs$args, nrow)
   )
 
-  cpp_function_registration <- glue::glue_collapse(cpp_function_registration, sep  = "\n")
+  cpp_function_registration <- glue::glue_collapse(cpp_function_registration, sep = "\n")
 
-  extra_includes <-  character()
+  extra_includes <- character()
   if (pkg_links_to_rcpp(path)) {
-    extra_includes <- c(extra_includes, "#include <cpp11/R.hpp>", "#include <Rcpp.h>", "using namespace Rcpp;")
+    extra_includes <- c(extra_includes, "#include <headers/R.hpp>", "#include <Rcpp.h>", "using namespace Rcpp;")
   }
 
   pkg_types <- c(
@@ -114,7 +113,7 @@ cpp_register <- function(path = ".", quiet = !is_interactive(), extension = c(".
       // clang-format off
 
       {extra_includes}
-      #include "cpp11/declarations.hpp"
+      #include "headers/declarations.hpp"
       #include <R_ext/Visibility.h>
 
       {cpp_functions_definitions}
@@ -129,7 +128,7 @@ cpp_register <- function(path = ".", quiet = !is_interactive(), extension = c(".
         R_forceSymbols(dll, TRUE);
       }}
       ',
-      call_entries = glue::glue_collapse(call_entries, "\n")
+    call_entries = glue::glue_collapse(call_entries, "\n")
   ))
 
   if (!quiet) {
@@ -169,7 +168,8 @@ generate_cpp_functions <- function(funs, package = "cpp11") {
   funs$calls <- mapply(wrap_call, funs$name, funs$return_type, funs$args, SIMPLIFY = TRUE)
   funs$package <- package
 
-  out <- glue::glue_data(funs,
+  out <- glue::glue_data(
+    funs,
     '
     // {basename(file)}
     {return_type} {name}({real_params});
@@ -193,20 +193,22 @@ generate_init_functions <- function(funs) {
   funs$declaration_params <- vcapply(funs$args, glue_collapse_data, "{type} {name}")
   funs$call_params <- vcapply(funs$args, `[[`, "name")
 
-  declarations <- glue::glue_data(funs,
-    '
+  declarations <- glue::glue_data(
+    funs,
+    "
     {return_type} {name}({declaration_params});
-    '
+    "
   )
 
   declarations <- paste0("\n", glue::glue_collapse(declarations, "\n"), "\n")
 
-  calls <- glue::glue_data(funs,
-    '
+  calls <- glue::glue_data(
+    funs,
+    "
       {name}({call_params});
-    '
+    "
   )
-  calls <- paste0("\n", glue::glue_collapse(calls, "\n"));
+  calls <- paste0("\n", glue::glue_collapse(calls, "\n"))
 
   list(
     declarations = declarations,
@@ -221,7 +223,7 @@ generate_r_functions <- function(funs, package = "cpp11", use_package = FALSE) {
     package_call <- glue::glue(', PACKAGE = "{package}"')
     package_names <- glue::glue_data(funs, '"_{package}_{name}"')
   } else {
-    package_names <- glue::glue_data(funs, '`_{package}_{name}`')
+    package_names <- glue::glue_data(funs, "`_{package}_{name}`")
     package_call <- ""
   }
 
@@ -231,21 +233,21 @@ generate_r_functions <- function(funs, package = "cpp11", use_package = FALSE) {
   funs$params <- vcapply(funs$list_params, function(x) if (nzchar(x)) paste0(", ", x) else x)
   is_void <- funs$return_type == "void"
   funs$calls <- ifelse(is_void,
-    glue::glue_data(funs, 'invisible(.Call({package_names}{params}{package_call}))'),
-    glue::glue_data(funs, '.Call({package_names}{params}{package_call})')
+    glue::glue_data(funs, "invisible(.Call({package_names}{params}{package_call}))"),
+    glue::glue_data(funs, ".Call({package_names}{params}{package_call})")
   )
 
-  out <- glue::glue_data(funs, '
+  out <- glue::glue_data(funs, "
     {name} <- function({list_params}) {{
       {calls}
     }}
-    ')
+    ")
   out <- glue::glue_collapse(out, sep = "\n\n")
   unclass(out)
 }
 
 wrap_call <- function(name, return_type, args) {
-  call <- glue::glue('{name}({list_params})', list_params = glue_collapse_data(args, "cpp11::as_cpp<cpp11::decay_t<{type}>>({name})"))
+  call <- glue::glue("{name}({list_params})", list_params = glue_collapse_data(args, "cpp11::as_cpp<cpp11::decay_t<{type}>>({name})"))
   if (return_type == "void") {
     unclass(glue::glue("  {call};\n    return R_NilValue;", .trim = FALSE))
   } else {
@@ -256,7 +258,8 @@ wrap_call <- function(name, return_type, args) {
 get_call_entries <- function(path, names, package) {
   con <- textConnection("res", local = TRUE, open = "w")
 
-  withr::with_collate("C",
+  withr::with_collate(
+    "C",
     tools::package_native_routine_registration_skeleton(path,
       con,
       character_only = FALSE,
@@ -274,7 +277,7 @@ get_call_entries <- function(path, names, package) {
     return("")
   }
 
-  redundant <- glue::glue_collapse(glue::glue('extern SEXP _{package}_{names}'), sep = '|')
+  redundant <- glue::glue_collapse(glue::glue("extern SEXP _{package}_{names}"), sep = "|")
 
   if (length(redundant) > 0 && nzchar(redundant)) {
     redundant <- paste0("^", redundant)
@@ -285,7 +288,7 @@ get_call_entries <- function(path, names, package) {
 
   call_calls <- startsWith(res, "extern SEXP")
 
-  if(any(call_calls)) {
+  if (any(call_calls)) {
     return(res[seq(start, end)])
   }
 
@@ -306,11 +309,10 @@ get_cpp_register_needs <- function() {
 }
 
 check_valid_attributes <- function(decorations, file = decorations$file) {
-
   bad_decor <- startsWith(decorations$decoration, "cpp11::") &
     (!decorations$decoration %in% c("cpp11::register", "cpp11::init", "cpp11::linking_to"))
 
-  if(any(bad_decor)) {
+  if (any(bad_decor)) {
     lines <- decorations$line[bad_decor]
     names <- decorations$decoration[bad_decor]
     bad_lines <- glue::glue_collapse(glue::glue("- Invalid attribute `{names}` on
@@ -320,6 +322,5 @@ check_valid_attributes <- function(decorations, file = decorations$file) {
       {bad_lines}
       ")
     stop(msg, call. = FALSE)
-
   }
 }
diff --git a/R/source.R b/R/source.R
index fc9124d5..5edfd80e 100644
--- a/R/source.R
+++ b/R/source.R
@@ -24,7 +24,7 @@
 #' @examples
 #'
 #' cpp_source(
-#'   code = '#include "cpp11/integers.hpp"
+#'   code = '#include "headers/integers.hpp"
 #'
 #'   [[cpp11::register]]
 #'   int num_odd(cpp11::integers x) {
@@ -36,15 +36,15 @@
 #'     }
 #'     return total;
 #'   }
-#'   ')
+#'   '
+#' )
 #'
 #' num_odd(as.integer(c(1:10, 15, 23)))
 #'
 #' if (interactive() && require("progress")) {
-#'
-#' cpp_source(
-#'   code = '
-#' #include <cpp11/R.hpp>
+#'   cpp_source(
+#'     code = '
+#' #include <headers/R.hpp>
 #' #include <RProgress.h>
 #'
 #' [[cpp11::linking_to("progress")]]
@@ -59,9 +59,10 @@
 #'     pb.tick();
 #'   }
 #' }
-#' ')
+#' '
+#'   )
 #'
-#' show_progress()
+#'   show_progress()
 #' }
 #'
 #' @export
@@ -96,7 +97,7 @@ cpp_source <- function(file, code = NULL, env = parent.frame(), clean = TRUE, qu
   # file now points to another location
   file.copy(file, file.path(new_dir, name))
 
-  #change variable name to reflect this
+  # change variable name to reflect this
   new_file_path <- file.path(new_dir, name)
   new_file_name <- basename(new_file_path)
 
@@ -106,14 +107,14 @@ cpp_source <- function(file, code = NULL, env = parent.frame(), clean = TRUE, qu
     all_decorations <- decor::cpp_decorations(dir, is_attribute = TRUE)
   )
 
-  #provide original path for error messages
+  # provide original path for error messages
   check_valid_attributes(all_decorations, file = orig_file_path)
 
   funs <- get_registered_functions(all_decorations, "cpp11::register", quiet = quiet)
   cpp_functions_definitions <- generate_cpp_functions(funs, package = package)
 
   cpp_path <- file.path(dirname(new_file_path), "cpp11.cpp")
-  brio::write_lines(c('#include "cpp11/declarations.hpp"', "using namespace ::cpp11;", cpp_functions_definitions), cpp_path)
+  brio::write_lines(c('#include "headers/declarations.hpp"', "using namespace ::cpp11;", cpp_functions_definitions), cpp_path)
 
   linking_to <- union(get_linking_to(all_decorations), "cpp11")
 
@@ -156,7 +157,7 @@ generate_cpp_name <- function(name, loaded_dlls = c("cpp11", names(getLoadedDLLs
   root <- tools::file_path_sans_ext(basename(name))
   count <- 2
   new_name <- root
-  while(new_name %in% loaded_dlls) {
+  while (new_name %in% loaded_dlls) {
     new_name <- sprintf("%s_%i", root, count)
     count <- count + 1
   }
@@ -184,12 +185,17 @@ generate_makevars <- function(includes, cxx_std) {
 #' @rdname cpp_source
 #' @export
 cpp_function <- function(code, env = parent.frame(), clean = TRUE, quiet = TRUE, cxx_std = Sys.getenv("CXX_STD", "CXX11")) {
-  cpp_source(code = paste(c('#include "cpp11.hpp"',
+  cpp_source(
+    code = paste(
+      c(
+        '#include "cpp11.hpp"',
         "using namespace ::cpp11;",
         "namespace writable = ::cpp11::writable;",
         "[[cpp11::register]]",
-        code),
-      collapse = "\n"),
+        code
+      ),
+      collapse = "\n"
+    ),
     env = env,
     clean = clean,
     quiet = quiet,
@@ -202,15 +208,20 @@ utils::globalVariables("f")
 #' @rdname cpp_source
 #' @export
 cpp_eval <- function(code, env = parent.frame(), clean = TRUE, quiet = TRUE, cxx_std = Sys.getenv("CXX_STD", "CXX11")) {
-  cpp_source(code = paste(c('#include "cpp11.hpp"',
+  cpp_source(
+    code = paste(
+      c(
+        '#include "cpp11.hpp"',
         "using namespace ::cpp11;",
         "namespace writable = ::cpp11::writable;",
         "[[cpp11::register]]",
         "SEXP f() { return as_sexp(",
         code,
         ");",
-        "}"),
-      collapse = "\n"),
+        "}"
+      ),
+      collapse = "\n"
+    ),
     env = env,
     clean = clean,
     quiet = quiet,
diff --git a/R/utils.R b/R/utils.R
index 0dddfaf9..e4e0e473 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -43,18 +43,18 @@ is_windows <- function() {
 # use for stop_if_not_installed(), because rlang itself could be one of the
 # input pkgs.
 is_interactive <- function() {
-    opt <- getOption("rlang_interactive", NULL)
-    if (!is.null(opt)) {
-        return(opt)
-    }
-    if (isTRUE(getOption("knitr.in.progress"))) {
-        return(FALSE)
-    }
-    if (isTRUE(getOption("rstudio.notebook.executing"))) {
-        return(FALSE)
-    }
-    if (identical(Sys.getenv("TESTTHAT"), "true")) {
-        return(FALSE)
-    }
-    interactive()
+  opt <- getOption("rlang_interactive", NULL)
+  if (!is.null(opt)) {
+    return(opt)
+  }
+  if (isTRUE(getOption("knitr.in.progress"))) {
+    return(FALSE)
+  }
+  if (isTRUE(getOption("rstudio.notebook.executing"))) {
+    return(FALSE)
+  }
+  if (identical(Sys.getenv("TESTTHAT"), "true")) {
+    return(FALSE)
+  }
+  interactive()
 }
diff --git a/R/vendor.R b/R/vendor.R
index 5fe10fe2..09148b63 100644
--- a/R/vendor.R
+++ b/R/vendor.R
@@ -4,18 +4,18 @@
 #' project is using. It is often used in the go language community.
 #'
 #' This function vendors cpp11 into your package by copying the cpp11
-#' headers into the `inst/include` folder of your package and adding
-#' 'cpp11 version: XYZ' to the top of the files, where XYZ is the version of
-#' cpp11 currently installed on your machine.
+#' headers into the `src/vendor` folder and adding 'cpp11 version: XYZ' to the
+#' top of the files, where XYZ is the version of cpp11 currently installed on
+#' your machine.
 #'
 #' If you choose to vendor the headers you should _remove_ `LinkingTo:
-#' cpp11` from your DESCRIPTION.
+#' cpp11` from your DESCRIPTION. This is done automatically by this function.
 #'
 #' **Note**: vendoring places the responsibility of updating the code on
 #' **you**. Bugfixes and new features in cpp11 will not be available for your
 #' code until you run `cpp_vendor()` again.
 #'
-#' @inheritParams cpp_register
+#' @param path The path to vendor the code into.
 #' @return The file path to the vendored code (invisibly).
 #' @export
 #' @examples
@@ -26,18 +26,18 @@
 #' # vendor the cpp11 headers into the directory
 #' cpp_vendor(dir)
 #'
-#' list.files(file.path(dir, "inst", "include", "cpp11"))
+#' list.files(file.path(dir, "src", "vendor"))
 #'
 #' # cleanup
 #' unlink(dir, recursive = TRUE)
-cpp_vendor <- function(path = ".") {
-  new <- file.path(path, "inst", "include", "cpp11")
+cpp_vendor <- function(path = "./src/vendor") {
+  new <- file.path(path, "cpp11")
 
   if (dir.exists(new)) {
     stop("'", new, "' already exists\n * run unlink('", new, "', recursive = TRUE)", call. = FALSE)
   }
 
-  dir.create(new , recursive = TRUE, showWarnings = FALSE)
+  dir.create(new, recursive = TRUE, showWarnings = FALSE)
 
   current <- system.file("include", "cpp11", package = "cpp11")
   if (!nzchar(current)) {
@@ -59,5 +59,67 @@ cpp_vendor <- function(path = ".") {
     writeLines(c(cpp11_header, readLines(f)), file.path(new, basename(f)))
   }
 
+  # Additional steps to make vendoring work ----
+
+  # 1. Check if `src/Makevars` exists
+  makevars_exists <- file.exists("src/Makevars")
+
+  # 2. If makevars exists, it should have a line that reads
+  # `PKG_CPPFLAGS = -I../inst/include` or similar
+
+  vendor_line <- paste0(" -I", new)
+
+  if (isTRUE(makevars_exists)) {
+    makevars <- readLines("src/Makevars")
+
+    if (any(grepl("^PKG_CPPFLAGS", makevars))) {
+      cat("There is a `PKG_CPPFLAGS` line in src/Makevars. It will be modified.\n")
+
+      # which line contains `PKG_CPPFLAGS`?
+      cppflags_line <- grep("^PKG_CPPFLAGS", makevars)
+
+      # append the vendoring line
+      if (!grepl(vendor_line, makevars[cppflags_line])) {
+        makevars[cppflags_line] <- paste0(makevars[cppflags_line], vendor_line)
+      }
+
+      writeLines(makevars, "src/Makevars")
+    } else {
+      # add the line
+      makevars <- c(makevars, paste0("PKG_CPPFLAGS = ", vendor_line))
+
+      writeLines(makevars, "src/Makevars")
+    }
+
+    cat("The existing src/Makevars was modified. Please check it.\n")
+  } else {
+    # create the file
+    writeLines(paste0("PKG_CPPFLAGS = ", vendor_line), "src/Makevars")
+
+    # warn about the change
+    cat("A new src/Makevars file was created.\n")
+  }
+
+  # 3. `DESCRIPTION` now should not have `LinkingTo: cpp11` or `LinkingTo: \n\tcpp11`
+  description <- readLines("DESCRIPTION")
+
+  cpp11_in_desc <- any(
+    grepl("LinkingTo: cpp11", description),
+    grepl("LinkingTo: ", description),
+    grepl("    cpp11", description)
+  )
+
+  if (isTRUE(cpp11_in_desc)) {
+    # remove the lines
+    description <- description[!grepl("LinkingTo: cpp11", description)]
+    description <- description[!grepl("LinkingTo: ", description)]
+    description <- description[!grepl("    cpp11", description)]
+
+    writeLines(description, "DESCRIPTION")
+
+    # warn about the change
+    cat("`LinkingTo: cpp11` was removed from DESCRIPTION.\n")
+  }
+
   invisible(new)
 }
diff --git a/cpp11test/bench/grow.R b/cpp11test/bench/grow.R
index a7bc7171..4c9b776a 100644
--- a/cpp11test/bench/grow.R
+++ b/cpp11test/bench/grow.R
@@ -1,9 +1,7 @@
 pkgload::load_all("cpp11test")
 
-bench::press(len = 10 ^ (0:7),
-  {
-    bench::mark(
-      .Call(cpp11_grow_, len)
-    )
-  }
-)
+bench::press(len = 10^(0:7), {
+  bench::mark(
+    .Call(cpp11_grow_, len)
+  )
+})
diff --git a/cpp11test/bench/protect.R b/cpp11test/bench/protect.R
index 989a8e1c..f79a3b0d 100644
--- a/cpp11test/bench/protect.R
+++ b/cpp11test/bench/protect.R
@@ -1,6 +1,7 @@
 pkgload::load_all("cpp11test")
 
-bench::press(n = 10000,
+bench::press(
+  n = 10000,
   bench::mark(
     protect_one_(1:10, n),
     protect_one_cpp11_(1:10, n),
@@ -9,7 +10,8 @@ bench::press(n = 10000,
   )
 )
 
-bench::press(n = 10000,
+bench::press(
+  n = 10000,
   bench::mark(
     protect_many_(n),
     protect_many_cpp11_(n),
diff --git a/cpp11test/bench/sum.R b/cpp11test/bench/sum.R
index 6bf2760d..f4be2e70 100644
--- a/cpp11test/bench/sum.R
+++ b/cpp11test/bench/sum.R
@@ -8,13 +8,15 @@ cases <- expand.grid(
 )
 
 # Add special case
-cases <- do.call(rbind,
+cases <- do.call(
+  rbind,
   list(
     list(len = 3e6, vector = "normal", method = "for2"),
     list(len = 3e6, vector = "normal", method = "foreach2"),
     list(len = 3e6, vector = "altrep", method = "foreach2"),
-    cases)
+    cases
   )
+)
 
 bench::press(
   .grid = cases,
diff --git a/cpp11test/src/add.cpp b/cpp11test/src/add.cpp
index 3a3bb4df..95561c25 100644
--- a/cpp11test/src/add.cpp
+++ b/cpp11test/src/add.cpp
@@ -1,4 +1,4 @@
-#include "cpp11/doubles.hpp"
+#include "headers/doubles.hpp"
 
 [[cpp11::register]] SEXP cpp11_add_vec_for_(cpp11::writable::doubles x, double num) {
   R_xlen_t n = x.size();
diff --git a/cpp11test/src/cpp11.cpp b/cpp11test/src/cpp11.cpp
index 6120c333..506b2e6d 100644
--- a/cpp11test/src/cpp11.cpp
+++ b/cpp11test/src/cpp11.cpp
@@ -1,10 +1,10 @@
 // Generated by cpp11: do not edit by hand
 // clang-format off
 
-#include <cpp11/R.hpp>
+#include <headers/R.hpp>
 #include <Rcpp.h>
 using namespace Rcpp;
-#include "cpp11/declarations.hpp"
+#include "headers/declarations.hpp"
 #include <R_ext/Visibility.h>
 
 // add.cpp
diff --git a/cpp11test/src/data_frame.cpp b/cpp11test/src/data_frame.cpp
index 08729155..fe4a6fc0 100644
--- a/cpp11test/src/data_frame.cpp
+++ b/cpp11test/src/data_frame.cpp
@@ -1,6 +1,6 @@
-#include "cpp11/integers.hpp"
-#include "cpp11/list.hpp"
-#include "cpp11/strings.hpp"
+#include "headers/integers.hpp"
+#include "headers/list.hpp"
+#include "headers/strings.hpp"
 
 [[cpp11::register]] SEXP data_frame_() {
   using namespace cpp11::literals;
diff --git a/cpp11test/src/errors.cpp b/cpp11test/src/errors.cpp
index 79f061ee..a571902f 100644
--- a/cpp11test/src/errors.cpp
+++ b/cpp11test/src/errors.cpp
@@ -1,5 +1,5 @@
-#include "cpp11/function.hpp"
-#include "cpp11/protect.hpp"
+#include "headers/function.hpp"
+#include "headers/protect.hpp"
 using namespace cpp11;
 
 [[cpp11::register]] void my_stop_n1fmt(std::string mystring) { cpp11::stop(mystring); }
diff --git a/cpp11test/src/errors_fmt.cpp b/cpp11test/src/errors_fmt.cpp
index 6c3ef8bc..96bf341d 100644
--- a/cpp11test/src/errors_fmt.cpp
+++ b/cpp11test/src/errors_fmt.cpp
@@ -1,6 +1,6 @@
 #define CPP11_USE_FMT
-#include "cpp11/function.hpp"
-#include "cpp11/protect.hpp"
+#include "headers/function.hpp"
+#include "headers/protect.hpp"
 using namespace cpp11;
 
 [[cpp11::register]] void my_stop(std::string mystring, int myarg) {
diff --git a/cpp11test/src/grow.cpp b/cpp11test/src/grow.cpp
index eb3f620b..ba587029 100644
--- a/cpp11test/src/grow.cpp
+++ b/cpp11test/src/grow.cpp
@@ -1,4 +1,4 @@
-#include "cpp11/doubles.hpp"
+#include "headers/doubles.hpp"
 
 [[cpp11::register]] cpp11::writable::doubles grow_(R_xlen_t n) {
   cpp11::writable::doubles x;
diff --git a/cpp11test/src/insert.cpp b/cpp11test/src/insert.cpp
index 913d71b8..6a71afe6 100644
--- a/cpp11test/src/insert.cpp
+++ b/cpp11test/src/insert.cpp
@@ -1,4 +1,4 @@
-#include "cpp11/doubles.hpp"
+#include "headers/doubles.hpp"
 
 [[cpp11::register]] SEXP cpp11_insert_(SEXP num_sxp) {
   R_xlen_t num = INTEGER(num_sxp)[0];
diff --git a/cpp11test/src/matrix.cpp b/cpp11test/src/matrix.cpp
index 10348945..a484bcff 100644
--- a/cpp11test/src/matrix.cpp
+++ b/cpp11test/src/matrix.cpp
@@ -1,6 +1,6 @@
-#include "cpp11/matrix.hpp"
+#include "headers/matrix.hpp"
 #include "Rmath.h"
-#include "cpp11/doubles.hpp"
+#include "headers/doubles.hpp"
 using namespace cpp11;
 
 [[cpp11::register]] SEXP gibbs_cpp(int N, int thin) {
diff --git a/cpp11test/src/release.cpp b/cpp11test/src/release.cpp
index 7b321e45..6be8d514 100644
--- a/cpp11test/src/release.cpp
+++ b/cpp11test/src/release.cpp
@@ -1,5 +1,5 @@
 #include <vector>
-#include "cpp11/sexp.hpp"
+#include "headers/sexp.hpp"
 
 #include "Rcpp.h"
 
diff --git a/cpp11test/src/safe.cpp b/cpp11test/src/safe.cpp
index 175f24ec..b12d254d 100644
--- a/cpp11test/src/safe.cpp
+++ b/cpp11test/src/safe.cpp
@@ -1,6 +1,6 @@
 #include <cstring>
-#include "cpp11/doubles.hpp"
-#include "cpp11/protect.hpp"
+#include "headers/doubles.hpp"
+#include "headers/protect.hpp"
 
 [[cpp11::register]] SEXP cpp11_safe_(SEXP x_sxp) {
   SEXP err = R_NilValue;
diff --git a/cpp11test/src/sum.cpp b/cpp11test/src/sum.cpp
index e685c7d1..25cd691c 100644
--- a/cpp11test/src/sum.cpp
+++ b/cpp11test/src/sum.cpp
@@ -1,5 +1,5 @@
 #include <numeric>
-#include "cpp11/doubles.hpp"
+#include "headers/doubles.hpp"
 
 [[cpp11::register]] double sum_dbl_for_(cpp11::doubles x) {
   double sum = 0.;
diff --git a/cpp11test/src/sum_int.cpp b/cpp11test/src/sum_int.cpp
index 922f6e76..79bd22af 100644
--- a/cpp11test/src/sum_int.cpp
+++ b/cpp11test/src/sum_int.cpp
@@ -1,5 +1,5 @@
 #include <numeric>
-#include "cpp11/integers.hpp"
+#include "headers/integers.hpp"
 
 [[cpp11::register]] double sum_int_for_(cpp11::integers x) {
   double sum = 0.;
diff --git a/cpp11test/src/test-as.cpp b/cpp11test/src/test-as.cpp
index ddbb9974..ca087f0b 100644
--- a/cpp11test/src/test-as.cpp
+++ b/cpp11test/src/test-as.cpp
@@ -2,7 +2,7 @@
 #include <string>
 #include <vector>
 
-#include "cpp11/declarations.hpp"
+#include "headers/declarations.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-data_frame.cpp b/cpp11test/src/test-data_frame.cpp
index e692712b..20f67bd9 100644
--- a/cpp11test/src/test-data_frame.cpp
+++ b/cpp11test/src/test-data_frame.cpp
@@ -1,7 +1,7 @@
-#include "cpp11/data_frame.hpp"
-#include "cpp11/function.hpp"
-#include "cpp11/integers.hpp"
-#include "cpp11/strings.hpp"
+#include "headers/data_frame.hpp"
+#include "headers/function.hpp"
+#include "headers/integers.hpp"
+#include "headers/strings.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-doubles.cpp b/cpp11test/src/test-doubles.cpp
index a7423e1e..31216cc2 100644
--- a/cpp11test/src/test-doubles.cpp
+++ b/cpp11test/src/test-doubles.cpp
@@ -1,9 +1,9 @@
 #include <cstring>
-#include "cpp11/doubles.hpp"
-#include "cpp11/function.hpp"
-#include "cpp11/integers.hpp"
-#include "cpp11/sexp.hpp"
-#include "cpp11/strings.hpp"
+#include "headers/doubles.hpp"
+#include "headers/function.hpp"
+#include "headers/integers.hpp"
+#include "headers/sexp.hpp"
+#include "headers/strings.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-environment.cpp b/cpp11test/src/test-environment.cpp
index 370b6018..55b2b57a 100644
--- a/cpp11test/src/test-environment.cpp
+++ b/cpp11test/src/test-environment.cpp
@@ -1,7 +1,7 @@
-#include "cpp11/as.hpp"
-#include "cpp11/environment.hpp"
-#include "cpp11/function.hpp"
-#include "cpp11/strings.hpp"
+#include "headers/as.hpp"
+#include "headers/environment.hpp"
+#include "headers/function.hpp"
+#include "headers/strings.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-external_pointer.cpp b/cpp11test/src/test-external_pointer.cpp
index 897fd4f2..325760c5 100644
--- a/cpp11test/src/test-external_pointer.cpp
+++ b/cpp11test/src/test-external_pointer.cpp
@@ -1,5 +1,5 @@
 #include <iostream>
-#include "cpp11/external_pointer.hpp"
+#include "headers/external_pointer.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-function.cpp b/cpp11test/src/test-function.cpp
index 678a5ee2..c19e4139 100644
--- a/cpp11test/src/test-function.cpp
+++ b/cpp11test/src/test-function.cpp
@@ -1,4 +1,4 @@
-#include "cpp11/function.hpp"
+#include "headers/function.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-integers.cpp b/cpp11test/src/test-integers.cpp
index 6f876c57..ef4d3896 100644
--- a/cpp11test/src/test-integers.cpp
+++ b/cpp11test/src/test-integers.cpp
@@ -1,8 +1,8 @@
 #include "Rversion.h"
-#include "cpp11/doubles.hpp"
-#include "cpp11/function.hpp"
-#include "cpp11/integers.hpp"
-#include "cpp11/strings.hpp"
+#include "headers/doubles.hpp"
+#include "headers/function.hpp"
+#include "headers/integers.hpp"
+#include "headers/strings.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-list.cpp b/cpp11test/src/test-list.cpp
index 0abf6002..51738f62 100644
--- a/cpp11test/src/test-list.cpp
+++ b/cpp11test/src/test-list.cpp
@@ -1,9 +1,9 @@
-#include "cpp11/doubles.hpp"
-#include "cpp11/integers.hpp"
-#include "cpp11/list.hpp"
-#include "cpp11/logicals.hpp"
-#include "cpp11/raws.hpp"
-#include "cpp11/strings.hpp"
+#include "headers/doubles.hpp"
+#include "headers/integers.hpp"
+#include "headers/list.hpp"
+#include "headers/logicals.hpp"
+#include "headers/raws.hpp"
+#include "headers/strings.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-list_of.cpp b/cpp11test/src/test-list_of.cpp
index 08d62dcf..930addfb 100644
--- a/cpp11test/src/test-list_of.cpp
+++ b/cpp11test/src/test-list_of.cpp
@@ -1,7 +1,7 @@
-#include "cpp11/doubles.hpp"
-#include "cpp11/list.hpp"
-#include "cpp11/list_of.hpp"
-#include "cpp11/strings.hpp"
+#include "headers/doubles.hpp"
+#include "headers/list.hpp"
+#include "headers/list_of.hpp"
+#include "headers/strings.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-logicals.cpp b/cpp11test/src/test-logicals.cpp
index 6c9b136a..170c412e 100644
--- a/cpp11test/src/test-logicals.cpp
+++ b/cpp11test/src/test-logicals.cpp
@@ -1,4 +1,4 @@
-#include "cpp11/logicals.hpp"
+#include "headers/logicals.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-matrix.cpp b/cpp11test/src/test-matrix.cpp
index 693d6ec7..4b98c9fb 100644
--- a/cpp11test/src/test-matrix.cpp
+++ b/cpp11test/src/test-matrix.cpp
@@ -1,7 +1,7 @@
-#include "cpp11/doubles.hpp"
-#include "cpp11/function.hpp"
-#include "cpp11/integers.hpp"
-#include "cpp11/matrix.hpp"
+#include "headers/doubles.hpp"
+#include "headers/function.hpp"
+#include "headers/integers.hpp"
+#include "headers/matrix.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-nas.cpp b/cpp11test/src/test-nas.cpp
index a0ca5848..dcaf4024 100644
--- a/cpp11test/src/test-nas.cpp
+++ b/cpp11test/src/test-nas.cpp
@@ -1,7 +1,7 @@
-#include "cpp11/doubles.hpp"
-#include "cpp11/integers.hpp"
-#include "cpp11/r_bool.hpp"
-#include "cpp11/r_string.hpp"
+#include "headers/doubles.hpp"
+#include "headers/integers.hpp"
+#include "headers/r_bool.hpp"
+#include "headers/r_string.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-protect-nested.cpp b/cpp11test/src/test-protect-nested.cpp
index 2679a5f7..384a62d9 100644
--- a/cpp11test/src/test-protect-nested.cpp
+++ b/cpp11test/src/test-protect-nested.cpp
@@ -1,5 +1,5 @@
-#include "cpp11/function.hpp"
-#include "cpp11/protect.hpp"
+#include "headers/function.hpp"
+#include "headers/protect.hpp"
 #include "testthat.h"
 
 #ifdef HAS_UNWIND_PROTECT
diff --git a/cpp11test/src/test-protect.cpp b/cpp11test/src/test-protect.cpp
index 2bd2dadf..323029c6 100644
--- a/cpp11test/src/test-protect.cpp
+++ b/cpp11test/src/test-protect.cpp
@@ -12,7 +12,7 @@
 // clang-format on
 
 #define CPP11_USE_FMT
-#include "cpp11/protect.hpp"
+#include "headers/protect.hpp"
 #include "testthat.h"
 
 #ifdef HAS_UNWIND_PROTECT
diff --git a/cpp11test/src/test-raws.cpp b/cpp11test/src/test-raws.cpp
index ecae6db6..c3f0fd25 100644
--- a/cpp11test/src/test-raws.cpp
+++ b/cpp11test/src/test-raws.cpp
@@ -1,4 +1,4 @@
-#include "cpp11/raws.hpp"
+#include "headers/raws.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-sexp.cpp b/cpp11test/src/test-sexp.cpp
index d9e7800e..9acee94a 100644
--- a/cpp11test/src/test-sexp.cpp
+++ b/cpp11test/src/test-sexp.cpp
@@ -1,4 +1,4 @@
-#include "cpp11/list.hpp"
+#include "headers/list.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-string.cpp b/cpp11test/src/test-string.cpp
index 98661a53..0953744f 100644
--- a/cpp11test/src/test-string.cpp
+++ b/cpp11test/src/test-string.cpp
@@ -1,4 +1,4 @@
-#include "cpp11/strings.hpp"
+#include "headers/strings.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/src/test-strings.cpp b/cpp11test/src/test-strings.cpp
index 3a11e935..7584be1b 100644
--- a/cpp11test/src/test-strings.cpp
+++ b/cpp11test/src/test-strings.cpp
@@ -1,6 +1,6 @@
 #include <cstring>
-#include "cpp11/sexp.hpp"
-#include "cpp11/strings.hpp"
+#include "headers/sexp.hpp"
+#include "headers/strings.hpp"
 
 #include <testthat.h>
 
diff --git a/cpp11test/tests/testthat/test-doubles.R b/cpp11test/tests/testthat/test-doubles.R
index a7016bd0..fa5197f7 100644
--- a/cpp11test/tests/testthat/test-doubles.R
+++ b/cpp11test/tests/testthat/test-doubles.R
@@ -1,5 +1,4 @@
 test_that("doubles iterators work with normal vectors", {
-
   len <- 1e5
   set.seed(42)
   x <- rnorm(len)
@@ -12,7 +11,6 @@ test_that("doubles iterators work with normal vectors", {
 })
 
 test_that("doubles iterators work with altrep vectors", {
-
   len <- 1e5
   seq_double <- function(x) as.double(seq_len(x))
 
diff --git a/cpp11test/tests/testthat/test-matrix.R b/cpp11test/tests/testthat/test-matrix.R
index a43f59b0..34df89ca 100644
--- a/cpp11test/tests/testthat/test-matrix.R
+++ b/cpp11test/tests/testthat/test-matrix.R
@@ -7,7 +7,7 @@ test_that("row_sums gives same result as rowSums", {
   expect_equal(row_sums(x), rowSums(x))
 
   y <- cbind(x1 = 3, x2 = c(4:1, 2:5))
-  y[3, ] <- NA;
+  y[3, ] <- NA
   expect_equal(row_sums(y), rowSums(y))
 })
 
@@ -20,6 +20,6 @@ test_that("col_sums gives same result as colSums", {
   expect_equal(col_sums(x), colSums(x))
 
   y <- cbind(3, c(4:1, 2:5))
-  y[3, ] <- NA;
+  y[3, ] <- NA
   expect_equal(col_sums(y), colSums(y))
 })
diff --git a/cpp11test/tests/testthat/test_formatted_errors.R b/cpp11test/tests/testthat/test_formatted_errors.R
index f4cfa8e5..f5ec6cc3 100644
--- a/cpp11test/tests/testthat/test_formatted_errors.R
+++ b/cpp11test/tests/testthat/test_formatted_errors.R
@@ -5,7 +5,8 @@ test_that("cpp11::stop formatting works", {
 
   test2 <- c(3, 5, 7)
   expect_error(my_stop("You've tested this {} times", test2[1]), "You've tested this 3 times",
-               fixed = TRUE)
+    fixed = TRUE
+  )
 })
 test_that("cpp11::warning formatting works", {
   test1 <- "warning"
diff --git a/inst/include/cpp11.hpp b/inst/include/cpp11.hpp
index 71e1cf1d..fa81c052 100644
--- a/inst/include/cpp11.hpp
+++ b/inst/include/cpp11.hpp
@@ -1,24 +1,24 @@
 #pragma once
 
-#include "cpp11/R.hpp"
-#include "cpp11/altrep.hpp"
-#include "cpp11/as.hpp"
-#include "cpp11/attribute_proxy.hpp"
-#include "cpp11/data_frame.hpp"
-#include "cpp11/doubles.hpp"
-#include "cpp11/environment.hpp"
-#include "cpp11/external_pointer.hpp"
-#include "cpp11/function.hpp"
-#include "cpp11/integers.hpp"
-#include "cpp11/list.hpp"
-#include "cpp11/list_of.hpp"
-#include "cpp11/logicals.hpp"
-#include "cpp11/matrix.hpp"
-#include "cpp11/named_arg.hpp"
-#include "cpp11/protect.hpp"
-#include "cpp11/r_bool.hpp"
-#include "cpp11/r_string.hpp"
-#include "cpp11/r_vector.hpp"
-#include "cpp11/raws.hpp"
-#include "cpp11/sexp.hpp"
-#include "cpp11/strings.hpp"
+#include "headers/R.hpp"
+#include "headers/altrep.hpp"
+#include "headers/as.hpp"
+#include "headers/attribute_proxy.hpp"
+#include "headers/data_frame.hpp"
+#include "headers/doubles.hpp"
+#include "headers/environment.hpp"
+#include "headers/external_pointer.hpp"
+#include "headers/function.hpp"
+#include "headers/integers.hpp"
+#include "headers/list.hpp"
+#include "headers/list_of.hpp"
+#include "headers/logicals.hpp"
+#include "headers/matrix.hpp"
+#include "headers/named_arg.hpp"
+#include "headers/protect.hpp"
+#include "headers/r_bool.hpp"
+#include "headers/r_string.hpp"
+#include "headers/r_vector.hpp"
+#include "headers/raws.hpp"
+#include "headers/sexp.hpp"
+#include "headers/strings.hpp"
diff --git a/inst/include/cpp11/R.hpp b/inst/include/headers/R.hpp
similarity index 97%
rename from inst/include/cpp11/R.hpp
rename to inst/include/headers/R.hpp
index 8d6751f1..91f2d40f 100644
--- a/inst/include/cpp11/R.hpp
+++ b/inst/include/headers/R.hpp
@@ -25,7 +25,7 @@
 // clang-format on
 
 #include <type_traits>
-#include "cpp11/altrep.hpp"
+#include "headers/altrep.hpp"
 
 namespace cpp11 {
 namespace literals {
diff --git a/inst/include/cpp11/altrep.hpp b/inst/include/headers/altrep.hpp
similarity index 100%
rename from inst/include/cpp11/altrep.hpp
rename to inst/include/headers/altrep.hpp
diff --git a/inst/include/cpp11/as.hpp b/inst/include/headers/as.hpp
similarity index 98%
rename from inst/include/cpp11/as.hpp
rename to inst/include/headers/as.hpp
index 682f12b5..255ed8cf 100644
--- a/inst/include/cpp11/as.hpp
+++ b/inst/include/headers/as.hpp
@@ -7,8 +7,8 @@
 #include <string>       // for string, basic_string
 #include <type_traits>  // for decay, enable_if, is_same, is_convertible
 
-#include "cpp11/R.hpp"        // for SEXP, SEXPREC, Rf_xlength, R_xlen_t
-#include "cpp11/protect.hpp"  // for stop, protect, safe, protect::function
+#include "headers/R.hpp"        // for SEXP, SEXPREC, Rf_xlength, R_xlen_t
+#include "headers/protect.hpp"  // for stop, protect, safe, protect::function
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/attribute_proxy.hpp b/inst/include/headers/attribute_proxy.hpp
similarity index 84%
rename from inst/include/cpp11/attribute_proxy.hpp
rename to inst/include/headers/attribute_proxy.hpp
index 64e7436b..c0adf44d 100644
--- a/inst/include/cpp11/attribute_proxy.hpp
+++ b/inst/include/headers/attribute_proxy.hpp
@@ -3,9 +3,9 @@
 #include <initializer_list>  // for initializer_list
 #include <string>            // for string, basic_string
 
-#include "cpp11/R.hpp"        // for SEXP, SEXPREC, Rf_install, PROTECT, Rf_...
-#include "cpp11/as.hpp"       // for as_sexp
-#include "cpp11/protect.hpp"  // for protect, safe, protect::function
+#include "headers/R.hpp"        // for SEXP, SEXPREC, Rf_install, PROTECT, Rf_...
+#include "headers/as.hpp"       // for as_sexp
+#include "headers/protect.hpp"  // for protect, safe, protect::function
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/data_frame.hpp b/inst/include/headers/data_frame.hpp
similarity index 90%
rename from inst/include/cpp11/data_frame.hpp
rename to inst/include/headers/data_frame.hpp
index f1caad51..4a652062 100644
--- a/inst/include/cpp11/data_frame.hpp
+++ b/inst/include/headers/data_frame.hpp
@@ -7,10 +7,10 @@
 #include <utility>           // for move
 
 #include "R_ext/Arith.h"              // for NA_INTEGER
-#include "cpp11/R.hpp"                // for Rf_xlength, SEXP, SEXPREC, INTEGER
-#include "cpp11/attribute_proxy.hpp"  // for attribute_proxy
-#include "cpp11/list.hpp"             // for list, r_vector<>::r_vector, r_v...
-#include "cpp11/r_vector.hpp"         // for r_vector
+#include "headers/R.hpp"                // for Rf_xlength, SEXP, SEXPREC, INTEGER
+#include "headers/attribute_proxy.hpp"  // for attribute_proxy
+#include "headers/list.hpp"             // for list, r_vector<>::r_vector, r_v...
+#include "headers/r_vector.hpp"         // for r_vector
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/declarations.hpp b/inst/include/headers/declarations.hpp
similarity index 100%
rename from inst/include/cpp11/declarations.hpp
rename to inst/include/headers/declarations.hpp
diff --git a/inst/include/cpp11/doubles.hpp b/inst/include/headers/doubles.hpp
similarity index 91%
rename from inst/include/cpp11/doubles.hpp
rename to inst/include/headers/doubles.hpp
index 9782346d..ff373bb2 100644
--- a/inst/include/cpp11/doubles.hpp
+++ b/inst/include/headers/doubles.hpp
@@ -5,12 +5,12 @@
 #include <initializer_list>  // for initializer_list
 
 #include "R_ext/Arith.h"        // for ISNA
-#include "cpp11/R.hpp"          // for SEXP, SEXPREC, Rf_allocVector, REAL
-#include "cpp11/as.hpp"         // for as_sexp
-#include "cpp11/named_arg.hpp"  // for named_arg
-#include "cpp11/protect.hpp"    // for SEXP, SEXPREC, REAL_ELT, R_Preserve...
-#include "cpp11/r_vector.hpp"   // for vector, vector<>::proxy, vector<>::...
-#include "cpp11/sexp.hpp"       // for sexp
+#include "headers/R.hpp"          // for SEXP, SEXPREC, Rf_allocVector, REAL
+#include "headers/as.hpp"         // for as_sexp
+#include "headers/named_arg.hpp"  // for named_arg
+#include "headers/protect.hpp"    // for SEXP, SEXPREC, REAL_ELT, R_Preserve...
+#include "headers/r_vector.hpp"   // for vector, vector<>::proxy, vector<>::...
+#include "headers/sexp.hpp"       // for sexp
 
 // Specializations for doubles
 
diff --git a/inst/include/cpp11/environment.hpp b/inst/include/headers/environment.hpp
similarity index 86%
rename from inst/include/cpp11/environment.hpp
rename to inst/include/headers/environment.hpp
index 64fbc553..0b1df9de 100644
--- a/inst/include/cpp11/environment.hpp
+++ b/inst/include/headers/environment.hpp
@@ -3,17 +3,17 @@
 #include <string>  // for string, basic_string
 
 #include "Rversion.h"         // for R_VERSION, R_Version
-#include "cpp11/R.hpp"        // for SEXP, SEXPREC, Rf_install, Rf_findVarIn...
-#include "cpp11/as.hpp"       // for as_sexp
-#include "cpp11/protect.hpp"  // for protect, protect::function, safe, unwin...
-#include "cpp11/sexp.hpp"     // for sexp
+#include "headers/R.hpp"        // for SEXP, SEXPREC, Rf_install, Rf_findVarIn...
+#include "headers/as.hpp"       // for as_sexp
+#include "headers/protect.hpp"  // for protect, protect::function, safe, unwin...
+#include "headers/sexp.hpp"     // for sexp
 
 #if R_VERSION >= R_Version(4, 0, 0)
 #define HAS_REMOVE_VAR_FROM_FRAME
 #endif
 
 #ifndef HAS_REMOVE_VAR_FROM_FRAME
-#include "cpp11/function.hpp"
+#include "headers/function.hpp"
 #endif
 
 namespace cpp11 {
diff --git a/inst/include/cpp11/external_pointer.hpp b/inst/include/headers/external_pointer.hpp
similarity index 92%
rename from inst/include/cpp11/external_pointer.hpp
rename to inst/include/headers/external_pointer.hpp
index 6956b061..5a83fa42 100644
--- a/inst/include/cpp11/external_pointer.hpp
+++ b/inst/include/headers/external_pointer.hpp
@@ -4,11 +4,11 @@
 #include <memory>       // for bad_weak_ptr
 #include <type_traits>  // for add_lvalue_reference
 
-#include "cpp11/R.hpp"         // for SEXP, SEXPREC, TYPEOF, R_NilValue, R_C...
-#include "cpp11/protect.hpp"   // for protect, safe, protect::function
-#include "cpp11/r_bool.hpp"    // for r_bool
-#include "cpp11/r_vector.hpp"  // for type_error
-#include "cpp11/sexp.hpp"      // for sexp
+#include "headers/R.hpp"         // for SEXP, SEXPREC, TYPEOF, R_NilValue, R_C...
+#include "headers/protect.hpp"   // for protect, safe, protect::function
+#include "headers/r_bool.hpp"    // for r_bool
+#include "headers/r_vector.hpp"  // for type_error
+#include "headers/sexp.hpp"      // for sexp
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/function.hpp b/inst/include/headers/function.hpp
similarity index 90%
rename from inst/include/cpp11/function.hpp
rename to inst/include/headers/function.hpp
index c1679d97..68549dbf 100644
--- a/inst/include/cpp11/function.hpp
+++ b/inst/include/headers/function.hpp
@@ -6,11 +6,11 @@
 #include <string>   // for string, basic_string
 #include <utility>  // for forward
 
-#include "cpp11/R.hpp"          // for SEXP, SEXPREC, CDR, Rf_install, SETCAR
-#include "cpp11/as.hpp"         // for as_sexp
-#include "cpp11/named_arg.hpp"  // for named_arg
-#include "cpp11/protect.hpp"    // for protect, protect::function, safe
-#include "cpp11/sexp.hpp"       // for sexp
+#include "headers/R.hpp"          // for SEXP, SEXPREC, CDR, Rf_install, SETCAR
+#include "headers/as.hpp"         // for as_sexp
+#include "headers/named_arg.hpp"  // for named_arg
+#include "headers/protect.hpp"    // for protect, protect::function, safe
+#include "headers/sexp.hpp"       // for sexp
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/integers.hpp b/inst/include/headers/integers.hpp
similarity index 90%
rename from inst/include/cpp11/integers.hpp
rename to inst/include/headers/integers.hpp
index 1159e2f3..a268841e 100644
--- a/inst/include/cpp11/integers.hpp
+++ b/inst/include/headers/integers.hpp
@@ -5,13 +5,13 @@
 #include <initializer_list>  // for initializer_list
 
 #include "R_ext/Arith.h"              // for NA_INTEGER
-#include "cpp11/R.hpp"                // for SEXP, SEXPREC, Rf_allocVector
-#include "cpp11/as.hpp"               // for as_sexp
-#include "cpp11/attribute_proxy.hpp"  // for attribute_proxy
-#include "cpp11/named_arg.hpp"        // for named_arg
-#include "cpp11/protect.hpp"          // for preserved
-#include "cpp11/r_vector.hpp"         // for r_vector, r_vector<>::proxy
-#include "cpp11/sexp.hpp"             // for sexp
+#include "headers/R.hpp"                // for SEXP, SEXPREC, Rf_allocVector
+#include "headers/as.hpp"               // for as_sexp
+#include "headers/attribute_proxy.hpp"  // for attribute_proxy
+#include "headers/named_arg.hpp"        // for named_arg
+#include "headers/protect.hpp"          // for preserved
+#include "headers/r_vector.hpp"         // for r_vector, r_vector<>::proxy
+#include "headers/sexp.hpp"             // for sexp
 
 // Specializations for integers
 
diff --git a/inst/include/cpp11/list.hpp b/inst/include/headers/list.hpp
similarity index 88%
rename from inst/include/cpp11/list.hpp
rename to inst/include/headers/list.hpp
index 64dd987b..72af2fc0 100644
--- a/inst/include/cpp11/list.hpp
+++ b/inst/include/headers/list.hpp
@@ -2,13 +2,13 @@
 
 #include <initializer_list>  // for initializer_list
 
-#include "cpp11/R.hpp"                // for SEXP, SEXPREC, SET_VECTOR_ELT
-#include "cpp11/attribute_proxy.hpp"  // for attribute_proxy
-#include "cpp11/named_arg.hpp"        // for named_arg
-#include "cpp11/protect.hpp"          // for preserved
-#include "cpp11/r_string.hpp"         // for r_string
-#include "cpp11/r_vector.hpp"         // for r_vector, r_vector<>::proxy
-#include "cpp11/sexp.hpp"             // for sexp
+#include "headers/R.hpp"                // for SEXP, SEXPREC, SET_VECTOR_ELT
+#include "headers/attribute_proxy.hpp"  // for attribute_proxy
+#include "headers/named_arg.hpp"        // for named_arg
+#include "headers/protect.hpp"          // for preserved
+#include "headers/r_string.hpp"         // for r_string
+#include "headers/r_vector.hpp"         // for r_vector, r_vector<>::proxy
+#include "headers/sexp.hpp"             // for sexp
 
 // Specializations for list
 
diff --git a/inst/include/cpp11/list_of.hpp b/inst/include/headers/list_of.hpp
similarity index 93%
rename from inst/include/cpp11/list_of.hpp
rename to inst/include/headers/list_of.hpp
index bd5ddd86..8dcdeb1d 100644
--- a/inst/include/cpp11/list_of.hpp
+++ b/inst/include/headers/list_of.hpp
@@ -2,8 +2,8 @@
 
 #include <string>  // for string, basic_string
 
-#include "cpp11/R.hpp"     // for R_xlen_t, SEXP, SEXPREC, LONG_VECTOR_SUPPORT
-#include "cpp11/list.hpp"  // for list
+#include "headers/R.hpp"     // for R_xlen_t, SEXP, SEXPREC, LONG_VECTOR_SUPPORT
+#include "headers/list.hpp"  // for list
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/logicals.hpp b/inst/include/headers/logicals.hpp
similarity index 89%
rename from inst/include/cpp11/logicals.hpp
rename to inst/include/headers/logicals.hpp
index 6a4e2cfa..d0e0e78e 100644
--- a/inst/include/cpp11/logicals.hpp
+++ b/inst/include/headers/logicals.hpp
@@ -4,13 +4,13 @@
 #include <array>             // for array
 #include <initializer_list>  // for initializer_list
 
-#include "cpp11/R.hpp"                // for SEXP, SEXPREC, Rf_all...
-#include "cpp11/attribute_proxy.hpp"  // for attribute_proxy
-#include "cpp11/named_arg.hpp"        // for named_arg
-#include "cpp11/protect.hpp"          // for preserved
-#include "cpp11/r_bool.hpp"           // for r_bool
-#include "cpp11/r_vector.hpp"         // for r_vector, r_vector<>::proxy
-#include "cpp11/sexp.hpp"             // for sexp
+#include "headers/R.hpp"                // for SEXP, SEXPREC, Rf_all...
+#include "headers/attribute_proxy.hpp"  // for attribute_proxy
+#include "headers/named_arg.hpp"        // for named_arg
+#include "headers/protect.hpp"          // for preserved
+#include "headers/r_bool.hpp"           // for r_bool
+#include "headers/r_vector.hpp"         // for r_vector, r_vector<>::proxy
+#include "headers/sexp.hpp"             // for sexp
 
 // Specializations for logicals
 
diff --git a/inst/include/cpp11/matrix.hpp b/inst/include/headers/matrix.hpp
similarity index 96%
rename from inst/include/cpp11/matrix.hpp
rename to inst/include/headers/matrix.hpp
index 9a8454fe..34942ffc 100644
--- a/inst/include/cpp11/matrix.hpp
+++ b/inst/include/headers/matrix.hpp
@@ -3,11 +3,11 @@
 #include <iterator>
 #include <string>  // for string
 
-#include "cpp11/R.hpp"         // for SEXP, SEXPREC, R_xlen_t, INT...
-#include "cpp11/r_bool.hpp"    // for r_bool
-#include "cpp11/r_string.hpp"  // for r_string
-#include "cpp11/r_vector.hpp"  // for r_vector
-#include "cpp11/sexp.hpp"      // for sexp
+#include "headers/R.hpp"         // for SEXP, SEXPREC, R_xlen_t, INT...
+#include "headers/r_bool.hpp"    // for r_bool
+#include "headers/r_string.hpp"  // for r_string
+#include "headers/r_vector.hpp"  // for r_vector
+#include "headers/sexp.hpp"      // for sexp
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/named_arg.hpp b/inst/include/headers/named_arg.hpp
similarity index 86%
rename from inst/include/cpp11/named_arg.hpp
rename to inst/include/headers/named_arg.hpp
index 1768821a..0fda14ae 100644
--- a/inst/include/cpp11/named_arg.hpp
+++ b/inst/include/headers/named_arg.hpp
@@ -4,9 +4,9 @@
 
 #include <initializer_list>  // for initializer_list
 
-#include "cpp11/R.hpp"     // for SEXP, SEXPREC, literals
-#include "cpp11/as.hpp"    // for as_sexp
-#include "cpp11/sexp.hpp"  // for sexp
+#include "headers/R.hpp"     // for SEXP, SEXPREC, literals
+#include "headers/as.hpp"    // for as_sexp
+#include "headers/sexp.hpp"  // for sexp
 
 namespace cpp11 {
 class named_arg {
diff --git a/inst/include/cpp11/protect.hpp b/inst/include/headers/protect.hpp
similarity index 98%
rename from inst/include/cpp11/protect.hpp
rename to inst/include/headers/protect.hpp
index 86d7fccc..f1bd0483 100644
--- a/inst/include/cpp11/protect.hpp
+++ b/inst/include/headers/protect.hpp
@@ -6,8 +6,8 @@
 #include <string>     // for string, basic_string
 #include <tuple>      // for tuple, make_tuple
 
-// NB: cpp11/R.hpp must precede R_ext/Error.h to ensure R_NO_REMAP is defined
-#include "cpp11/R.hpp"  // for SEXP, SEXPREC, CDR, R_NilValue, CAR, R_Pres...
+// NB: headers/R.hpp must precede R_ext/Error.h to ensure R_NO_REMAP is defined
+#include "headers/R.hpp"  // for SEXP, SEXPREC, CDR, R_NilValue, CAR, R_Pres...
 
 #include "R_ext/Boolean.h"  // for Rboolean
 #include "R_ext/Error.h"    // for Rf_error, Rf_warning
diff --git a/inst/include/cpp11/r_bool.hpp b/inst/include/headers/r_bool.hpp
similarity index 88%
rename from inst/include/cpp11/r_bool.hpp
rename to inst/include/headers/r_bool.hpp
index a3bb18eb..af1448f8 100644
--- a/inst/include/cpp11/r_bool.hpp
+++ b/inst/include/headers/r_bool.hpp
@@ -5,11 +5,11 @@
 #include <type_traits>  // for is_convertible, enable_if
 
 #include "R_ext/Boolean.h"    // for Rboolean
-#include "cpp11/R.hpp"        // for SEXP, SEXPREC, ...
-#include "cpp11/as.hpp"       // for as_sexp
-#include "cpp11/protect.hpp"  // for unwind_protect, preserved
-#include "cpp11/r_vector.hpp"
-#include "cpp11/sexp.hpp"  // for sexp
+#include "headers/R.hpp"        // for SEXP, SEXPREC, ...
+#include "headers/as.hpp"       // for as_sexp
+#include "headers/protect.hpp"  // for unwind_protect, preserved
+#include "headers/r_vector.hpp"
+#include "headers/sexp.hpp"  // for sexp
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/r_string.hpp b/inst/include/headers/r_string.hpp
similarity index 90%
rename from inst/include/cpp11/r_string.hpp
rename to inst/include/headers/r_string.hpp
index 692b66ea..cf75a087 100644
--- a/inst/include/cpp11/r_string.hpp
+++ b/inst/include/headers/r_string.hpp
@@ -4,10 +4,10 @@
 #include <type_traits>  // for is_convertible, enable_if
 
 #include "R_ext/Memory.h"     // for vmaxget, vmaxset
-#include "cpp11/R.hpp"        // for SEXP, SEXPREC, Rf_mkCharCE, Rf_translat...
-#include "cpp11/as.hpp"       // for as_sexp
-#include "cpp11/protect.hpp"  // for unwind_protect, protect, protect::function
-#include "cpp11/sexp.hpp"     // for sexp
+#include "headers/R.hpp"        // for SEXP, SEXPREC, Rf_mkCharCE, Rf_translat...
+#include "headers/as.hpp"       // for as_sexp
+#include "headers/protect.hpp"  // for unwind_protect, protect, protect::function
+#include "headers/sexp.hpp"     // for sexp
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/r_vector.hpp b/inst/include/headers/r_vector.hpp
similarity index 98%
rename from inst/include/cpp11/r_vector.hpp
rename to inst/include/headers/r_vector.hpp
index 4831c2f5..ec97c9cf 100644
--- a/inst/include/cpp11/r_vector.hpp
+++ b/inst/include/headers/r_vector.hpp
@@ -13,11 +13,11 @@
 #include <type_traits>       // for decay, is_same, enable_if, is_c...
 #include <utility>           // for declval
 
-#include "cpp11/R.hpp"                // for R_xlen_t, SEXP, SEXPREC, Rf_xle...
-#include "cpp11/attribute_proxy.hpp"  // for attribute_proxy
-#include "cpp11/protect.hpp"          // for preserved
-#include "cpp11/r_string.hpp"         // for r_string
-#include "cpp11/sexp.hpp"             // for sexp
+#include "headers/R.hpp"                // for R_xlen_t, SEXP, SEXPREC, Rf_xle...
+#include "headers/attribute_proxy.hpp"  // for attribute_proxy
+#include "headers/protect.hpp"          // for preserved
+#include "headers/r_string.hpp"         // for r_string
+#include "headers/sexp.hpp"             // for sexp
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/raws.hpp b/inst/include/headers/raws.hpp
similarity index 90%
rename from inst/include/cpp11/raws.hpp
rename to inst/include/headers/raws.hpp
index a5cb392f..c441126e 100644
--- a/inst/include/cpp11/raws.hpp
+++ b/inst/include/headers/raws.hpp
@@ -5,12 +5,12 @@
 #include <cstdint>           // for uint8_t
 #include <initializer_list>  // for initializer_list
 
-#include "cpp11/R.hpp"                // for RAW, SEXP, SEXPREC, Rf_allocVector
-#include "cpp11/attribute_proxy.hpp"  // for attribute_proxy
-#include "cpp11/named_arg.hpp"        // for named_arg
-#include "cpp11/protect.hpp"          // for preserved
-#include "cpp11/r_vector.hpp"         // for r_vector, r_vector<>::proxy
-#include "cpp11/sexp.hpp"             // for sexp
+#include "headers/R.hpp"                // for RAW, SEXP, SEXPREC, Rf_allocVector
+#include "headers/attribute_proxy.hpp"  // for attribute_proxy
+#include "headers/named_arg.hpp"        // for named_arg
+#include "headers/protect.hpp"          // for preserved
+#include "headers/r_vector.hpp"         // for r_vector, r_vector<>::proxy
+#include "headers/sexp.hpp"             // for sexp
 
 // Specializations for raws
 
diff --git a/inst/include/cpp11/sexp.hpp b/inst/include/headers/sexp.hpp
similarity index 90%
rename from inst/include/cpp11/sexp.hpp
rename to inst/include/headers/sexp.hpp
index 1517c5af..c4d47ef7 100644
--- a/inst/include/cpp11/sexp.hpp
+++ b/inst/include/headers/sexp.hpp
@@ -4,9 +4,9 @@
 
 #include <string>  // for string, basic_string
 
-#include "cpp11/R.hpp"                // for SEXP, SEXPREC, REAL_ELT, R_NilV...
-#include "cpp11/attribute_proxy.hpp"  // for attribute_proxy
-#include "cpp11/protect.hpp"          // for preserved
+#include "headers/R.hpp"                // for SEXP, SEXPREC, REAL_ELT, R_NilV...
+#include "headers/attribute_proxy.hpp"  // for attribute_proxy
+#include "headers/protect.hpp"          // for preserved
 
 namespace cpp11 {
 
diff --git a/inst/include/cpp11/strings.hpp b/inst/include/headers/strings.hpp
similarity index 90%
rename from inst/include/cpp11/strings.hpp
rename to inst/include/headers/strings.hpp
index e312c231..886583e5 100644
--- a/inst/include/cpp11/strings.hpp
+++ b/inst/include/headers/strings.hpp
@@ -3,14 +3,14 @@
 #include <initializer_list>  // for initializer_list
 #include <string>            // for string, basic_string
 
-#include "cpp11/R.hpp"                // for SEXP, TYPEOF, SEXPREC, SET_STRI...
-#include "cpp11/as.hpp"               // for as_sexp
-#include "cpp11/attribute_proxy.hpp"  // for attribute_proxy
-#include "cpp11/named_arg.hpp"        // for named_arg
-#include "cpp11/protect.hpp"          // for preserved
-#include "cpp11/r_string.hpp"         // for r_string
-#include "cpp11/r_vector.hpp"         // for r_vector, r_vector<>::proxy
-#include "cpp11/sexp.hpp"             // for sexp
+#include "headers/R.hpp"                // for SEXP, TYPEOF, SEXPREC, SET_STRI...
+#include "headers/as.hpp"               // for as_sexp
+#include "headers/attribute_proxy.hpp"  // for attribute_proxy
+#include "headers/named_arg.hpp"        // for named_arg
+#include "headers/protect.hpp"          // for preserved
+#include "headers/r_string.hpp"         // for r_string
+#include "headers/r_vector.hpp"         // for r_vector, r_vector<>::proxy
+#include "headers/sexp.hpp"             // for sexp
 
 // Specializations for strings
 
diff --git a/man/cpp_source.Rd b/man/cpp_source.Rd
index 87164ef5..ffe75bd2 100644
--- a/man/cpp_source.Rd
+++ b/man/cpp_source.Rd
@@ -68,7 +68,7 @@ external packages. This is equivalent to putting those packages in the
 \examples{
 
 cpp_source(
-  code = '#include "cpp11/integers.hpp"
+  code = '#include "headers/integers.hpp"
 
   [[cpp11::register]]
   int num_odd(cpp11::integers x) {
@@ -88,7 +88,7 @@ if (interactive() && require("progress")) {
 
 cpp_source(
   code = '
-#include <cpp11/R.hpp>
+#include <headers/R.hpp>
 #include <RProgress.h>
 
 [[cpp11::linking_to("progress")]]
diff --git a/man/cpp_vendor.Rd b/man/cpp_vendor.Rd
index 857e49cf..a02f36de 100644
--- a/man/cpp_vendor.Rd
+++ b/man/cpp_vendor.Rd
@@ -4,10 +4,10 @@
 \alias{cpp_vendor}
 \title{Vendor the cpp11 dependency}
 \usage{
-cpp_vendor(path = ".")
+cpp_vendor(path = "./src/vendor")
 }
 \arguments{
-\item{path}{The path to the package root directory}
+\item{path}{The path to vendor the code into.}
 }
 \value{
 The file path to the vendored code (invisibly).
@@ -18,11 +18,11 @@ project is using. It is often used in the go language community.
 }
 \details{
 This function vendors cpp11 into your package by copying the cpp11
-headers into the \code{inst/include} folder of your package and adding
-'cpp11 version: XYZ' to the top of the files, where XYZ is the version of
-cpp11 currently installed on your machine.
+headers into the \code{src/vendor} folder and adding 'cpp11 version: XYZ' to the
+top of the files, where XYZ is the version of cpp11 currently installed on
+your machine.
 
-If you choose to vendor the headers you should \emph{remove} \code{LinkingTo: cpp11} from your DESCRIPTION.
+If you choose to vendor the headers you should \emph{remove} \code{LinkingTo: cpp11} from your DESCRIPTION. This is done automatically by this function.
 
 \strong{Note}: vendoring places the responsibility of updating the code on
 \strong{you}. Bugfixes and new features in cpp11 will not be available for your
@@ -36,7 +36,7 @@ dir.create(dir)
 # vendor the cpp11 headers into the directory
 cpp_vendor(dir)
 
-list.files(file.path(dir, "inst", "include", "cpp11"))
+list.files(file.path(dir, "src", "vendor"))
 
 # cleanup
 unlink(dir, recursive = TRUE)
diff --git a/tests/testthat/_snaps/register.md b/tests/testthat/_snaps/register.md
index 0e4b143a..75125c45 100644
--- a/tests/testthat/_snaps/register.md
+++ b/tests/testthat/_snaps/register.md
@@ -2,7 +2,7 @@
 
     Code
       cpp_register(p, quiet = FALSE)
-    Message <cliMessage>
+    Message
       i 1 functions decorated with [[cpp11::register]]
       v generated file 'cpp11.R'
       v generated file 'cpp11.cpp'
diff --git a/tests/testthat/_snaps/source.md b/tests/testthat/_snaps/source.md
index 15935031..ad9152aa 100644
--- a/tests/testthat/_snaps/source.md
+++ b/tests/testthat/_snaps/source.md
@@ -2,7 +2,8 @@
 
     Code
       cpp_source(i_do_not_exist)
-    Error <simpleError>
-      Can't find `file` at this path:
+    Condition
+      Error:
+      ! Can't find `file` at this path:
       {NON_EXISTENT_FILEPATH}
 
diff --git a/tests/testthat/test-register.R b/tests/testthat/test-register.R
index 130abcbe..e601d69a 100644
--- a/tests/testthat/test-register.R
+++ b/tests/testthat/test-register.R
@@ -50,7 +50,6 @@ describe("get_call_entries", {
   })
 
   it("returns an empty string for packages with .Call entries and NAMESPACE files", {
-
     # tools::package_native_routine_registration_skeleton is not available before R 3.4
     skip_if(getRversion() < "3.4")
 
@@ -63,7 +62,8 @@ describe("get_call_entries", {
     expect_match(call_entries[2], "extern SEXP bar[(](void)?[)]")
     expect_equal(
       call_entries[4:7],
-      c("static const R_CallMethodDef CallEntries[] = {",
+      c(
+        "static const R_CallMethodDef CallEntries[] = {",
         "    {\"bar\", (DL_FUNC) &bar, 0},",
         "    {NULL, NULL, 0}",
         "};"
@@ -78,12 +78,13 @@ describe("get_call_entries", {
 
     cpp_register(p)
     cpp_bindings <- file.path(p, "src", "cpp11.cpp")
-    expect_equal(read_file(cpp_bindings),
-                 "// Generated by cpp11: do not edit by hand
+    expect_equal(
+      read_file(cpp_bindings),
+      "// Generated by cpp11: do not edit by hand
 // clang-format off
 
 
-#include \"cpp11/declarations.hpp\"
+#include \"headers/declarations.hpp\"
 #include <R_ext/Visibility.h>
 
 // multiple.cpp
@@ -122,7 +123,8 @@ extern \"C\" attribute_visible void R_init_testPkg(DllInfo* dll){
   R_useDynamicSymbols(dll, FALSE);
   R_forceSymbols(dll, TRUE);
 }
-")
+"
+    )
   })
 })
 
@@ -236,8 +238,9 @@ describe("generate_cpp_functions", {
       args = list(tibble::tibble(type = character(), name = character()))
     )
 
-    expect_equal(generate_cpp_functions(funs),
-"// foo.cpp
+    expect_equal(
+      generate_cpp_functions(funs),
+      "// foo.cpp
 void foo();
 extern \"C\" SEXP _cpp11_foo() {
   BEGIN_CPP11
@@ -260,8 +263,9 @@ extern \"C\" SEXP _cpp11_foo() {
       args = list(tibble::tibble(type = character(), name = character()))
     )
 
-    expect_equal(generate_cpp_functions(funs, package = "mypkg"),
-"// foo.cpp
+    expect_equal(
+      generate_cpp_functions(funs, package = "mypkg"),
+      "// foo.cpp
 void foo();
 extern \"C\" SEXP _mypkg_foo() {
   BEGIN_CPP11
@@ -285,8 +289,9 @@ extern \"C\" SEXP _mypkg_foo() {
       args = list(tibble::tibble(type = character(), name = character()))
     )
 
-    expect_equal(generate_cpp_functions(funs),
-"// foo.cpp
+    expect_equal(
+      generate_cpp_functions(funs),
+      "// foo.cpp
 int foo();
 extern \"C\" SEXP _cpp11_foo() {
   BEGIN_CPP11
@@ -308,8 +313,9 @@ extern \"C\" SEXP _cpp11_foo() {
       args = list(tibble::tibble(type = "int", name = "bar"))
     )
 
-    expect_equal(generate_cpp_functions(funs),
-"// foo.cpp
+    expect_equal(
+      generate_cpp_functions(funs),
+      "// foo.cpp
 void foo(int bar);
 extern \"C\" SEXP _cpp11_foo(SEXP bar) {
   BEGIN_CPP11
@@ -332,8 +338,9 @@ extern \"C\" SEXP _cpp11_foo(SEXP bar) {
       args = list(tibble::tibble(type = "int", name = "bar"))
     )
 
-    expect_equal(generate_cpp_functions(funs),
-"// foo.cpp
+    expect_equal(
+      generate_cpp_functions(funs),
+      "// foo.cpp
 int foo(int bar);
 extern \"C\" SEXP _cpp11_foo(SEXP bar) {
   BEGIN_CPP11
@@ -358,8 +365,9 @@ extern \"C\" SEXP _cpp11_foo(SEXP bar) {
       )
     )
 
-    expect_equal(generate_cpp_functions(funs),
-"// foo.cpp
+    expect_equal(
+      generate_cpp_functions(funs),
+      "// foo.cpp
 int foo(int bar);
 extern \"C\" SEXP _cpp11_foo(SEXP bar) {
   BEGIN_CPP11
@@ -407,10 +415,12 @@ describe("generate_r_functions", {
       args = list(tibble::tibble(type = character(), name = character()))
     )
 
-    expect_equal(generate_r_functions(funs, package = "cpp11"),
-"foo <- function() {
+    expect_equal(
+      generate_r_functions(funs, package = "cpp11"),
+      "foo <- function() {
   invisible(.Call(`_cpp11_foo`))
-}")
+}"
+    )
   })
 
   it("returns the wrapped function for a single void function with no arguments and use_package = TRUE", {
@@ -425,10 +435,12 @@ describe("generate_r_functions", {
       args = list(tibble::tibble(type = character(), name = character()))
     )
 
-    expect_equal(generate_r_functions(funs, package = "cpp11", use_package = TRUE),
-"foo <- function() {
+    expect_equal(
+      generate_r_functions(funs, package = "cpp11", use_package = TRUE),
+      "foo <- function() {
   invisible(.Call(\"_cpp11_foo\", PACKAGE = \"cpp11\"))
-}")
+}"
+    )
   })
 
   it("returns the wrapped function for a single void function with no arguments and different package name", {
@@ -443,10 +455,12 @@ describe("generate_r_functions", {
       args = list(tibble::tibble(type = character(), name = character()))
     )
 
-    expect_equal(generate_r_functions(funs, package = "mypkg"),
-"foo <- function() {
+    expect_equal(
+      generate_r_functions(funs, package = "mypkg"),
+      "foo <- function() {
   invisible(.Call(`_mypkg_foo`))
-}")
+}"
+    )
   })
 
   it("returns the wrapped function for a single function with no arguments", {
@@ -461,10 +475,12 @@ describe("generate_r_functions", {
       args = list(tibble::tibble(type = character(), name = character()))
     )
 
-    expect_equal(generate_r_functions(funs, package = "cpp11"),
-"foo <- function() {
+    expect_equal(
+      generate_r_functions(funs, package = "cpp11"),
+      "foo <- function() {
   .Call(`_cpp11_foo`)
-}")
+}"
+    )
   })
 
   it("returns the wrapped function for a single function with no arguments and use_package = TRUE", {
@@ -479,10 +495,12 @@ describe("generate_r_functions", {
       args = list(tibble::tibble(type = character(), name = character()))
     )
 
-    expect_equal(generate_r_functions(funs, package = "cpp11", use_package = TRUE),
-"foo <- function() {
+    expect_equal(
+      generate_r_functions(funs, package = "cpp11", use_package = TRUE),
+      "foo <- function() {
   .Call(\"_cpp11_foo\", PACKAGE = \"cpp11\")
-}")
+}"
+    )
   })
 
   it("returns the wrapped function for a single void function with arguments", {
@@ -497,10 +515,12 @@ describe("generate_r_functions", {
       args = list(tibble::tibble(type = "int", name = "bar"))
     )
 
-    expect_equal(generate_r_functions(funs, package = "cpp11"),
-"foo <- function(bar) {
+    expect_equal(
+      generate_r_functions(funs, package = "cpp11"),
+      "foo <- function(bar) {
   invisible(.Call(`_cpp11_foo`, bar))
-}")
+}"
+    )
   })
 
   it("returns the wrapped function for a single function with arguments", {
@@ -515,10 +535,12 @@ describe("generate_r_functions", {
       args = list(tibble::tibble(type = "int", name = "bar"))
     )
 
-    expect_equal(generate_r_functions(funs, package = "cpp11"),
-"foo <- function(bar) {
+    expect_equal(
+      generate_r_functions(funs, package = "cpp11"),
+      "foo <- function(bar) {
   .Call(`_cpp11_foo`, bar)
-}")
+}"
+    )
   })
 
   it("returns the wrapped functions for multiple functions with arguments", {
@@ -536,14 +558,16 @@ describe("generate_r_functions", {
       )
     )
 
-    expect_equal(generate_r_functions(funs, package = "cpp11"),
-"foo <- function(bar) {
+    expect_equal(
+      generate_r_functions(funs, package = "cpp11"),
+      "foo <- function(bar) {
   .Call(`_cpp11_foo`, bar)
 }
 
 bar <- function(baz) {
   .Call(`_cpp11_bar`, baz)
-}")
+}"
+    )
   })
 })
 
@@ -554,10 +578,8 @@ describe("cpp_register", {
 
     dir.create(f)
     expect_equal(cpp_register(f), character())
-
   })
   it("works with a package that registers a single c++ function", {
-
     # tools::package_native_routine_registration_skeleton is not available before R 3.4
     skip_if(getRversion() < "3.4")
 
@@ -569,21 +591,24 @@ describe("cpp_register", {
 
     r_bindings <- file.path(p, "R", "cpp11.R")
     expect_true(file.exists(r_bindings))
-    expect_equal(read_file(r_bindings),
-"# Generated by cpp11: do not edit by hand
+    expect_equal(
+      read_file(r_bindings),
+      "# Generated by cpp11: do not edit by hand
 
 foo <- function() {
   .Call(`_testPkg_foo`)
 }
-")
+"
+    )
     cpp_bindings <- file.path(p, "src", "cpp11.cpp")
     expect_true(file.exists(cpp_bindings))
-    expect_equal(read_file(cpp_bindings),
-"// Generated by cpp11: do not edit by hand
+    expect_equal(
+      read_file(cpp_bindings),
+      "// Generated by cpp11: do not edit by hand
 // clang-format off
 
 
-#include \"cpp11/declarations.hpp\"
+#include \"headers/declarations.hpp\"
 #include <R_ext/Visibility.h>
 
 // single.cpp
@@ -606,7 +631,8 @@ extern \"C\" attribute_visible void R_init_testPkg(DllInfo* dll){
   R_useDynamicSymbols(dll, FALSE);
   R_forceSymbols(dll, TRUE);
 }
-")
+"
+    )
   })
 
   it("can be run without messages", {
diff --git a/tests/testthat/test-source.R b/tests/testthat/test-source.R
index 2945d51d..3be14872 100644
--- a/tests/testthat/test-source.R
+++ b/tests/testthat/test-source.R
@@ -2,7 +2,7 @@ test_that("cpp_source works with the `code` parameter", {
   skip_on_os("solaris")
   dll_info <- cpp_source(
     code = '
-    #include "cpp11/integers.hpp"
+    #include "headers/integers.hpp"
 
     [[cpp11::register]]
     int num_odd(cpp11::integers x) {
@@ -14,7 +14,8 @@ test_that("cpp_source works with the `code` parameter", {
       }
       return total;
     }
-    ', clean = TRUE)
+    ', clean = TRUE
+  )
   on.exit(dyn.unload(dll_info[["path"]]))
 
   expect_equal(num_odd(as.integer(c(1:10, 15, 23))), 7)
@@ -28,7 +29,8 @@ test_that("cpp_source works with the `file` parameter", {
     bool always_true() {
       return true;
     }
-    ", tf)
+    ", tf
+  )
   on.exit(unlink(tf))
 
   dll_info <- cpp_source(tf, clean = TRUE, quiet = TRUE)
@@ -45,7 +47,8 @@ test_that("cpp_source works with files called `cpp11.cpp`", {
     bool always_true() {
       return true;
     }
-    ", tf)
+    ", tf
+  )
   on.exit(unlink(tf))
 
   dll_info <- cpp_source(tf, clean = TRUE, quiet = TRUE)
@@ -55,14 +58,16 @@ test_that("cpp_source works with files called `cpp11.cpp`", {
 })
 
 test_that("cpp_source returns original file name on error", {
-
   expect_output(try(cpp_source(test_path("single_error.cpp"), clean = TRUE), silent = TRUE),
-               normalizePath(test_path("single_error.cpp"), winslash = "/"), fixed = TRUE)
+    normalizePath(test_path("single_error.cpp"), winslash = "/"),
+    fixed = TRUE
+  )
 
-  #error generated for incorrect attributes is separate from compilation errors
+  # error generated for incorrect attributes is separate from compilation errors
   expect_error(cpp_source(test_path("single_incorrect.cpp"), clean = TRUE),
-                normalizePath(test_path("single_incorrect.cpp"), winslash = "/"), fixed = TRUE)
-
+    normalizePath(test_path("single_incorrect.cpp"), winslash = "/"),
+    fixed = TRUE
+  )
 })
 
 test_that("cpp_source lets you set the C++ standard", {
@@ -77,7 +82,8 @@ test_that("cpp_source lets you set the C++ standard", {
       auto str = "hello_world"s;
       return str;
     }
-    ', tf)
+    ', tf
+  )
   on.exit(unlink(tf))
 
   dll_info <- cpp_source(tf, clean = TRUE, quiet = TRUE, cxx_std = "CXX14")
@@ -97,9 +103,9 @@ test_that("generate_cpp_name works", {
     "foo_2.cpp"
   )
 
-expect_equal(
-  generate_cpp_name("foo.cpp", loaded_dlls = c("foo", "foo_2")),
-  "foo_3.cpp"
+  expect_equal(
+    generate_cpp_name("foo.cpp", loaded_dlls = c("foo", "foo_2")),
+    "foo_3.cpp"
   )
 })
 
@@ -128,10 +134,12 @@ test_that("check_valid_attributes does not return an error if all registers are
     cpp11::writable::list x;
     x.push_back({"foo"_nm = 1});
     return x;
-  }'))
+  }')
+  )
   expect_error_free(
-    cpp11::cpp_source(clean = TRUE,
-      code = '#include <cpp11/R.hpp>
+    cpp11::cpp_source(
+      clean = TRUE,
+      code = '#include <headers/R.hpp>
               #include <RProgress.h>
 
               [[cpp11::linking_to("progress")]]
@@ -145,7 +153,8 @@ test_that("check_valid_attributes does not return an error if all registers are
                   pb.tick();
                 }
               }
-              ')
+              '
+    )
   )
 })
 
@@ -164,7 +173,8 @@ test_that("check_valid_attributes returns an error if one or more registers is i
     cpp11::writable::list x;
     x.push_back({"foo"_nm = 1});
     return x;
-  }'))
+  }')
+  )
 
   expect_error(
     cpp11::cpp_source(code = '#include <cpp11.hpp>
@@ -174,7 +184,8 @@ test_that("check_valid_attributes returns an error if one or more registers is i
     cpp11::writable::list x;
     x.push_back({"foo"_nm = 1});
     return x;
-  }'))
+  }')
+  )
 
   expect_error(
     cpp11::cpp_source(code = '#include <cpp11.hpp>
@@ -190,14 +201,15 @@ test_that("check_valid_attributes returns an error if one or more registers is i
     cpp11::writable::list x;
     x.push_back({"foo"_nm = 1});
     return x;
-  }'))
+  }')
+  )
 
 
 
   expect_error(
     cpp11::cpp_source(
       code = '
-      #include <cpp11/R.hpp>
+      #include <headers/R.hpp>
       #include <RProgress.h>
       [[cpp11::link_to("progress")]]
       [[cpp11::register]] void show_progress() {
@@ -208,7 +220,9 @@ test_that("check_valid_attributes returns an error if one or more registers is i
           pb.tick();
         }
       }
-'))
+'
+    )
+  )
 })
 
 test_that("cpp_source(d) functions work after sourcing file more than once", {
diff --git a/tests/testthat/test-vendor.R b/tests/testthat/test-vendor.R
index 361c9ad9..c4a37a90 100644
--- a/tests/testthat/test-vendor.R
+++ b/tests/testthat/test-vendor.R
@@ -24,8 +24,8 @@ describe("cpp_vendor", {
 
     cpp_vendor(pkg_path(pkg))
 
-    expect_true(dir.exists(file.path(p, "inst", "include", "cpp11")))
-    expect_true(file.exists(file.path(p, "inst", "include", "cpp11.hpp")))
-    expect_true(file.exists(file.path(p, "inst", "include", "cpp11", "declarations.hpp")))
+    expect_true(dir.exists(file.path(p, "src", "vendor", "cpp11")))
+    expect_true(file.exists(file.path(p, "src", "vendor", "cpp11.hpp")))
+    expect_true(file.exists(file.path(p, "src", "vendor", "headers", "declarations.hpp")))
   })
 })
diff --git a/vignettes/FAQ.Rmd b/vignettes/FAQ.Rmd
index 29d99340..05c4f3e6 100644
--- a/vignettes/FAQ.Rmd
+++ b/vignettes/FAQ.Rmd
@@ -455,7 +455,7 @@ set.seed(123)
 x <- sample(letters, 1e6, replace = TRUE)
 
 bench::mark(
-  test_extract_cpp11(x), 
+  test_extract_cpp11(x),
   test_extract_r_api(x)
 )
 ```
diff --git a/vignettes/converting.Rmd b/vignettes/converting.Rmd
index de4b8898..16cfd2fc 100644
--- a/vignettes/converting.Rmd
+++ b/vignettes/converting.Rmd
@@ -26,24 +26,24 @@ It is also a place to highlight some of the largest differences between Rcpp and
 
 ## Class comparison table
 
-| Rcpp                    | cpp11 (read-only)     | cpp11 (writable)            | cpp11 header                 |
-| ---                     | ---                   | ---                         | ---                          |
-| NumericVector           | doubles               | writable::doubles           | <cpp11/doubles.hpp>          |
-| NumericMatrix           | doubles_matrix<>      | writable::doubles_matrix<>  | <cpp11/doubles.hpp>          |
-| IntegerVector           | integers              | writable::integers          | <cpp11/integers.hpp>         |
-| IntegerMatrix           | integers_matrix<>     | writable::integers_matrix<> | <cpp11/integers.hpp>         |
-| CharacterVector         | strings               | writable::strings           | <cpp11/strings.hpp>          |
-| RawVector               | raws                  | writable::raws              | <cpp11/raws.hpp>             |
-| List                    | list                  | writable::list              | <cpp11/list.hpp>             |
-| RObject                 | sexp                  |                             | <cpp11/sexp.hpp>             |
-| XPtr                    |                       | external_pointer            | <cpp11/external_pointer.hpp> |
-| Environment             |                       | environment                 | <cpp11/environment.hpp>      |
-| Function                |                       | function                    | <cpp11/function.hpp>         |
-| Environment (namespace) |                       | package                     | <cpp11/function.hpp>         |
-| wrap                    |                       | as_sexp                     | <cpp11/as.hpp>               |
-| as                      |                       | as_cpp                      | <cpp11/as.hpp>               |
-| stop                    | stop                  |                             | <cpp11/protect.hpp>          |
-| checkUserInterrupt      | check_user_interrupt  |                             | <cpp11/protect.hpp>          |
+| Rcpp                    | cpp11 (read-only)     | cpp11 (writable)            | cpp11 header                   |
+| ---                     | ---                   | ---                         | ---                            |
+| NumericVector           | doubles               | writable::doubles           | <headers/doubles.hpp>          |
+| NumericMatrix           | doubles_matrix<>      | writable::doubles_matrix<>  | <headers/doubles.hpp>          |
+| IntegerVector           | integers              | writable::integers          | <headers/integers.hpp>         |
+| IntegerMatrix           | integers_matrix<>     | writable::integers_matrix<> | <headers/integers.hpp>         |
+| CharacterVector         | strings               | writable::strings           | <headers/strings.hpp>          |
+| RawVector               | raws                  | writable::raws              | <headers/raws.hpp>             |
+| List                    | list                  | writable::list              | <headers/list.hpp>             |
+| RObject                 | sexp                  |                             | <headers/sexp.hpp>             |
+| XPtr                    |                       | external_pointer            | <headers/external_pointer.hpp> |
+| Environment             |                       | environment                 | <headers/environment.hpp>      |
+| Function                |                       | function                    | <headers/function.hpp>         |
+| Environment (namespace) |                       | package                     | <headers/function.hpp>         |
+| wrap                    |                       | as_sexp                     | <headers/as.hpp>               |
+| as                      |                       | as_cpp                      | <headers/as.hpp>               |
+| stop                    | stop                  |                             | <headers/protect.hpp>          |
+| checkUserInterrupt      | check_user_interrupt  |                             | <headers/protect.hpp>          |
 
 ## Incomplete list of Rcpp features not included in cpp11
 
@@ -99,19 +99,17 @@ Because of this you can do ~10,000,000 vector appends with cpp11 in approximatel
 
 ```{r, message = FALSE, eval = should_run_benchmarks()}
 library(cpp11test)
-grid <- expand.grid(len = 10 ^ (0:7), pkg = "cpp11", stringsAsFactors = FALSE)
+grid <- expand.grid(len = 10^(0:7), pkg = "cpp11", stringsAsFactors = FALSE)
 grid <- rbind(
   grid,
-  expand.grid(len = 10 ^ (0:4), pkg = "rcpp", stringsAsFactors = FALSE)
+  expand.grid(len = 10^(0:4), pkg = "rcpp", stringsAsFactors = FALSE)
 )
-b_grow <- bench::press(.grid = grid,
-  {
-    fun = match.fun(sprintf("%sgrow_", ifelse(pkg == "cpp11", "", paste0(pkg, "_"))))
-    bench::mark(
-      fun(len)
-    )
-  }
-)[c("len", "pkg", "min", "mem_alloc", "n_itr", "n_gc")]
+b_grow <- bench::press(.grid = grid, {
+  fun <- match.fun(sprintf("%sgrow_", ifelse(pkg == "cpp11", "", paste0(pkg, "_"))))
+  bench::mark(
+    fun(len)
+  )
+})[c("len", "pkg", "min", "mem_alloc", "n_itr", "n_gc")]
 saveRDS(b_grow, "growth.Rds", version = 2)
 ```
 
@@ -186,7 +184,7 @@ You will need to include the appropriate STL header, in this case `<string>`.
 ### R API includes
 
 cpp11 conflicts with macros declared by some R headers unless the macros `R_NO_REMAP` and `STRICT_R_HEADERS` are defined.
-If you include `cpp11/R.hpp` before any R headers these macros will be defined appropriately, otherwise you may see errors like
+If you include `headers/R.hpp` before any R headers these macros will be defined appropriately, otherwise you may see errors like
 
 > R headers were included before cpp11 headers and at least one of R_NO_REMAP or STRICT_R_HEADERS was not defined.