Original computing environment

## # http://dirk.eddelbuettel.com/blog/2017/11/27/#011_faster_package_installation_one
## VER=
## CCACHE=ccache
## CC=$(CCACHE) gcc$(VER)
## CXX=$(CCACHE) g++$(VER)
## CXXFLAGS=-O3 -Wno-unused-variable -Wno-unused-function -Wno-unused-local-typedefs
## CXX11=$(CCACHE) g++$(VER)
## CXX14=$(CCACHE) g++$(VER)
## FLIBS = -L`gfortran -print-file-name=libgfortran.dylib | xargs dirname`
## FC=$(CCACHE) gfortran$(VER)
## F77=$(CCACHE) gfortran$(VER)
## ─ Session info ──────────────────────────────────────────────────────────
##  setting  value                       
##  version  R version 3.6.0 (2019-04-26)
##  os       macOS Mojave 10.14.4        
##  system   x86_64, darwin15.6.0        
##  ui       X11                         
##  language (EN)                        
##  collate  en_US.UTF-8                 
##  ctype    en_US.UTF-8                 
##  tz       America/Denver              
##  date     2019-05-16                  
## 
## ─ Packages ──────────────────────────────────────────────────────────────
##  package         * version    date       lib
##  assertthat        0.2.1      2019-03-21 [1]
##  backports         1.1.4      2019-04-10 [1]
##  base64enc         0.1-3      2015-07-28 [1]
##  broom             0.5.2      2019-04-07 [1]
##  callr             3.2.0      2019-03-15 [1]
##  cellranger        1.1.0      2016-07-27 [1]
##  cli               1.1.0      2019-03-19 [1]
##  colorspace        1.4-1      2019-03-18 [1]
##  crayon            1.3.4      2017-09-16 [1]
##  desc              1.2.0      2018-05-01 [1]
##  devtools          2.0.2      2019-04-08 [1]
##  digest            0.6.18     2018-10-10 [1]
##  donorheuristics * 0.0.0.9000 2019-05-02 [1]
##  dplyr           * 0.8.1      2019-05-14 [1]
##  evaluate          0.13       2019-02-12 [1]
##  forcats         * 0.4.0      2019-02-17 [1]
##  fs                1.3.1      2019-05-06 [1]
##  generics          0.0.2      2018-11-29 [1]
##  ggplot2         * 3.1.1      2019-04-07 [1]
##  glue              1.3.1      2019-03-12 [1]
##  gtable            0.3.0      2019-03-25 [1]
##  haven             2.1.0      2019-02-19 [1]
##  here            * 0.1        2017-05-28 [1]
##  hms               0.4.2      2018-03-10 [1]
##  htmltools         0.3.6      2017-04-28 [1]
##  httr              1.4.0      2018-12-11 [1]
##  jsonlite          1.6        2018-12-07 [1]
##  knitr             1.22       2019-03-08 [1]
##  lattice           0.20-38    2018-11-04 [1]
##  lazyeval          0.2.2      2019-03-15 [1]
##  lubridate         1.7.4      2018-04-11 [1]
##  magrittr          1.5        2014-11-22 [1]
##  memoise           1.1.0      2017-04-21 [1]
##  modelr            0.1.4      2019-02-18 [1]
##  munsell           0.5.0      2018-06-12 [1]
##  nlme              3.1-139    2019-04-09 [1]
##  pillar            1.4.0      2019-05-11 [1]
##  pkgbuild          1.0.3      2019-03-20 [1]
##  pkgconfig         2.0.2      2018-08-16 [1]
##  pkgload           1.0.2      2018-10-29 [1]
##  plyr              1.8.4      2016-06-08 [1]
##  prettyunits       1.0.2      2015-07-13 [1]
##  processx          3.3.1.9000 2019-05-14 [1]
##  ps                1.3.0      2018-12-21 [1]
##  purrr           * 0.3.2      2019-03-15 [1]
##  R6                2.4.0      2019-02-14 [1]
##  Rcpp              1.0.1      2019-03-17 [1]
##  readr           * 1.3.1      2018-12-21 [1]
##  readxl            1.3.1      2019-03-13 [1]
##  remotes           2.0.4      2019-04-10 [1]
##  rlang             0.3.4      2019-04-07 [1]
##  rmarkdown         1.12       2019-03-14 [1]
##  rprojroot         1.3-2      2018-01-03 [1]
##  rstudioapi        0.10       2019-03-19 [1]
##  rvest             0.3.3      2019-04-11 [1]
##  scales            1.0.0.9000 2019-05-10 [1]
##  sessioninfo       1.1.1      2018-11-05 [1]
##  stringi           1.4.3      2019-03-12 [1]
##  stringr         * 1.4.0      2019-02-10 [1]
##  testthat          2.1.1      2019-04-23 [1]
##  tibble          * 2.1.1      2019-03-16 [1]
##  tidyr           * 0.8.3      2019-03-01 [1]
##  tidyselect        0.2.5      2018-10-11 [1]
##  tidyverse       * 1.2.1      2017-11-14 [1]
##  usethis           1.5.0      2019-04-07 [1]
##  withr             2.1.2      2018-03-15 [1]
##  xfun              0.7        2019-05-14 [1]
##  xml2              1.2.0      2018-01-24 [1]
##  yaml              2.2.0      2018-07-25 [1]
##  source                          
##  CRAN (R 3.6.0)                  
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##  local                           
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##  Github (r-pkgs/processx@505cb1f)
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##  Github (r-lib/scales@7f6f4a5)   
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## 
## [1] /Library/Frameworks/R.framework/Versions/3.6/Resources/library
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