diff --git a/.github/workflows/rhub.yaml b/.github/workflows/rhub.yaml
deleted file mode 100644
index 74ec7b0..0000000
--- a/.github/workflows/rhub.yaml
+++ /dev/null
@@ -1,95 +0,0 @@
-# R-hub's generic GitHub Actions workflow file. It's canonical location is at
-# https://github.com/r-hub/actions/blob/v1/workflows/rhub.yaml
-# You can update this file to a newer version using the rhub2 package:
-#
-# rhub::rhub_setup()
-#
-# It is unlikely that you need to modify this file manually.
-
-name: R-hub
-run-name: "${{ github.event.inputs.id }}: ${{ github.event.inputs.name || format('Manually run by {0}', github.triggering_actor) }}"
-
-on:
-  workflow_dispatch:
-    inputs:
-      config:
-        description: 'A comma separated list of R-hub platforms to use.'
-        type: string
-        default: 'linux,windows,macos'
-      name:
-        description: 'Run name. You can leave this empty now.'
-        type: string
-      id:
-        description: 'Unique ID. You can leave this empty now.'
-        type: string
-
-jobs:
-
-  setup:
-    runs-on: ubuntu-latest
-    outputs:
-      containers: ${{ steps.rhub-setup.outputs.containers }}
-      platforms: ${{ steps.rhub-setup.outputs.platforms }}
-
-    steps:
-    # NO NEED TO CHECKOUT HERE
-    - uses: r-hub/actions/setup@v1
-      with:
-        config: ${{ github.event.inputs.config }}
-      id: rhub-setup
-
-  linux-containers:
-    needs: setup
-    if: ${{ needs.setup.outputs.containers != '[]' }}
-    runs-on: ubuntu-latest
-    name: ${{ matrix.config.label }}
-    strategy:
-      fail-fast: false
-      matrix:
-        config: ${{ fromJson(needs.setup.outputs.containers) }}
-    container:
-      image: ${{ matrix.config.container }}
-
-    steps:
-      - uses: r-hub/actions/checkout@v1
-      - uses: r-hub/actions/platform-info@v1
-        with:
-          token: ${{ secrets.RHUB_TOKEN }}
-          job-config: ${{ matrix.config.job-config }}
-      - uses: r-hub/actions/setup-deps@v1
-        with:
-          token: ${{ secrets.RHUB_TOKEN }}
-          job-config: ${{ matrix.config.job-config }}
-      - uses: r-hub/actions/run-check@v1
-        with:
-          token: ${{ secrets.RHUB_TOKEN }}
-          job-config: ${{ matrix.config.job-config }}
-
-  other-platforms:
-    needs: setup
-    if: ${{ needs.setup.outputs.platforms != '[]' }}
-    runs-on: ${{ matrix.config.os }}
-    name: ${{ matrix.config.label }}
-    strategy:
-      fail-fast: false
-      matrix:
-        config: ${{ fromJson(needs.setup.outputs.platforms) }}
-
-    steps:
-      - uses: r-hub/actions/checkout@v1
-      - uses: r-hub/actions/setup-r@v1
-        with:
-          job-config: ${{ matrix.config.job-config }}
-          token: ${{ secrets.RHUB_TOKEN }}
-      - uses: r-hub/actions/platform-info@v1
-        with:
-          token: ${{ secrets.RHUB_TOKEN }}
-          job-config: ${{ matrix.config.job-config }}
-      - uses: r-hub/actions/setup-deps@v1
-        with:
-          job-config: ${{ matrix.config.job-config }}
-          token: ${{ secrets.RHUB_TOKEN }}
-      - uses: r-hub/actions/run-check@v1
-        with:
-          job-config: ${{ matrix.config.job-config }}
-          token: ${{ secrets.RHUB_TOKEN }}
diff --git a/NAMESPACE b/NAMESPACE
index 71fec65..25f87b0 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -33,6 +33,7 @@ importFrom(lbfgs,lbfgs)
 importFrom(numDeriv,grad)
 importFrom(parallel,detectCores)
 importFrom(parallel,makeCluster)
+importFrom(parallel,stopCluster)
 importFrom(pbmcapply,pbmclapply)
 importFrom(purrr,map_dbl)
 importFrom(purrr,partial)
diff --git a/R/accept_reject.r b/R/accept_reject.r
index 1088023..88ed4e7 100644
--- a/R/accept_reject.r
+++ b/R/accept_reject.r
@@ -106,7 +106,7 @@
 #' @importFrom lbfgs lbfgs
 #' @importFrom purrr partial map_dbl
 #' @importFrom numDeriv grad
-#' @importFrom parallel detectCores makeCluster
+#' @importFrom parallel detectCores makeCluster stopCluster
 #' @importFrom stats dunif runif dweibull
 #' @importFrom utils capture.output
 #' @importFrom assertthat assert_that
@@ -245,13 +245,13 @@ accept_reject <-
           mc.cores = n_cores
           )))
     } else if(parallel && .Platform$OS.type == "windows"){
-      cl <- makeCluster(parallel::detectCores())
+      cl <- parallel::makeCluster(getOption("cl.cores", 2L))
       capture.output(
         r <- unlist(parallel::parLapply(
           X = n_each_core,
           fun = one_step
       )))
-      stopCluster(cl)
+      parallel::stopCluster(cl)
     } else {
       r <- one_step(n)
     }