Subject: Re: [bug#36602] [PATCH] Add node-build-system.

From: Julien Lepiller <[email-masked]>
Date: Sat, 13 Jul 2019 22:20:14 +0200

Le Sat, 13 Jul 2019 14:42:38 +0200,
Ludovic Courtès <[email-masked]> a écrit :

> Hello!
> 
> Nice work!  I wonder if this could be used for the ‘node-semver’
> package that arrived at about the same time:
> <https://issues.guix.gnu.org/issue/36599>.
> 
> Jelle Licht <[email-masked]> skribis:
> 
> >> +(define* (install #:key outputs inputs global? #:allow-other-keys)
> >> +  "Install the node module to the output store item. MODULENAME
> >> defines +under which name the module will be installed, GLOBAL?
> >> determines whether this +is an npm global install."
> >> +  (let* ((out          (assoc-ref outputs "out"))
> >> +         (src-dir      (getcwd))
> >> +         (tgt-dir      (string-append out "/lib"))
> >> +         (bin-dir      (string-append out "/bin"))
> >> +         (modulename   (string-append  (assoc-ref
> >> (read-package-data) "name")))
> >> +         (data         (read-package-data))
> >> +         (bin-conf     (assoc-ref data "bin"))
> >> +         (dependencies (match (assoc-ref data "dependencies")
> >> +                         ((@ deps ...) deps)  
> 
> Note that ‘@’ here matches anything.  Did you mean '@, which would
> match the @ symbol?
> 
> >> +                         (#f #f))))  
> > It might be better to write out most of these
> > names. I think we could also move `modulename' one line lower, so
> > it can become `(modulename (assoc-ref data "name"))'.  
> 
> I’m gratuitously nitpicking as well :-), but I think we should spell
> out names in general, so I’d propose s/src-dir/source/,
> s/tgt-dir/target/, etc.
> 
>   https://www.gnu.org/software/guix/manual/en/html_node/Formatting-Code.html
> 
> Anyway, thanks for working on it!
> 
> Ludo’.

Hopefully, the attached patch fixes your (and Jelle's) points. I also
fixed the default node package (it was node-lts, but that doesn't exist
anymore), made the configure phase return #t and fixed the
binary-configuration. I tested again on a few packages and they built
without issue.
From cb1f067cdf8dcfae23e01f86a12da032bc7d9fbb Mon Sep 17 00:00:00 2001
From: Jelle Licht <[email-masked]>
Date: Tue, 23 Aug 2016 05:23:55 +0200
Subject: [PATCH] build: Add node-build-system.

* guix/build/node-build-system.scm: New file.
* guix/build-system/node.scm: New file.
* guix/build/json.scm: New file.
* doc/guix.texi: Document it.
* Makefile.am: Added new files.

Co-Authored-By: Julien Lepiller <[email-masked]>
---
 Makefile.am                      |   3 +
 doc/guix.texi                    |  11 +
 guix/build-system/node.scm       | 135 +++++++++++
 guix/build/json.scm              | 387 +++++++++++++++++++++++++++++++
 guix/build/node-build-system.scm | 164 +++++++++++++
 5 files changed, 700 insertions(+)
 create mode 100644 guix/build-system/node.scm
 create mode 100644 guix/build/json.scm
 create mode 100644 guix/build/node-build-system.scm

diff --git a/Makefile.am b/Makefile.am
index 82eda6042a..9839bf27cc 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -125,6 +125,7 @@ MODULES =					\
   guix/build-system/guile.scm			\
   guix/build-system/haskell.scm			\
   guix/build-system/linux-module.scm		\
+  guix/build-system/node.scm			\
   guix/build-system/perl.scm			\
   guix/build-system/python.scm			\
   guix/build-system/ocaml.scm			\
@@ -170,6 +171,7 @@ MODULES =					\
   guix/build/gnu-build-system.scm		\
   guix/build/gnu-dist.scm			\
   guix/build/guile-build-system.scm		\
+  guix/build/node-build-system.scm		\
   guix/build/perl-build-system.scm		\
   guix/build/python-build-system.scm		\
   guix/build/ocaml-build-system.scm		\
@@ -182,6 +184,7 @@ MODULES =					\
   guix/build/haskell-build-system.scm		\
   guix/build/linux-module-build-system.scm	\
   guix/build/store-copy.scm			\
+  guix/build/json.scm				\
   guix/build/utils.scm				\
   guix/build/union.scm				\
   guix/build/profiles.scm			\
diff --git a/doc/guix.texi b/doc/guix.texi
index 5a8ad7ebda..4a9832d9e6 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -6333,6 +6333,17 @@ the module (in the "arguments" form of a package using the
 linux-module-build-system, use the key #:linux to specify it).
 @end defvr
 
+@defvr {Scheme Variable} node-build-system
+This variable is exported by @code{(guix build-system node)}.  It
+implements the build procedure used by @uref{http://nodejs.org,
+Node.js}, which implements an approximation of the @code{npm install}
+command, followed by an @code{npm test} command.
+
+Which Node.js package is used to interpret the @code{npm} commands can
+be specified with the @code{#:node} parameter which defaults to
+@code{node}.
+@end defvr
+
 Lastly, for packages that do not need anything as sophisticated, a
 ``trivial'' build system is provided.  It is trivial in the sense that
 it provides basically no support: it does not pull any implicit inputs,
diff --git a/guix/build-system/node.scm b/guix/build-system/node.scm
new file mode 100644
index 0000000000..05c24c47d5
--- /dev/null
+++ b/guix/build-system/node.scm
@@ -0,0 +1,135 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2016 Jelle Licht <[email-masked]>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (guix build-system node)
+  #:use-module (guix store)
+  #:use-module (guix build json)
+  #:use-module (guix build union)
+  #:use-module (guix utils)
+  #:use-module (guix packages)
+  #:use-module (guix derivations)
+  #:use-module (guix search-paths)
+  #:use-module (guix build-system)
+  #:use-module (guix build-system gnu)
+  #:use-module (ice-9 match)
+  #:export (npm-meta-uri
+            %node-build-system-modules
+            node-build
+            node-build-system))
+
+(define (npm-meta-uri name)
+  "Return a URI string for the metadata of node module NAME found in the npm
+registry."
+  (string-append "https://registry.npmjs.org/" name))
+
+(define %node-build-system-modules
+  ;; Build-side modules imported by default.
+  `((guix build node-build-system)
+    (guix build json)
+    (guix build union)
+    ,@%gnu-build-system-modules)) ;; TODO: Might be not needed
+
+(define (default-node)
+  "Return the default Node package."
+  ;; Lazily resolve the binding to avoid a circular dependency.
+  (let ((node (resolve-interface '(gnu packages node))))
+    (module-ref node 'node)))
+
+(define* (lower name
+                #:key source inputs native-inputs outputs system target
+                (node (default-node))
+                #:allow-other-keys
+                #:rest arguments)
+  "Return a bag for NAME."
+  (define private-keywords
+    '(#:source #:target #:node #:inputs #:native-inputs))
+
+  (and (not target)                    ;XXX: no cross-compilation
+       (bag
+         (name name)
+         (system system)
+         (host-inputs `(,@(if source
+                              `(("source" ,source))
+                              '())
+                        ,@inputs
+
+                        ;; Keep the standard inputs of 'gnu-build-system'.
+                        ,@(standard-packages)))
+         (build-inputs `(("node" ,node)
+                         ,@native-inputs))
+         (outputs outputs)
+         (build node-build)
+         (arguments (strip-keyword-arguments private-keywords arguments)))))
+
+(define* (node-build store name inputs
+                     #:key
+                     (npm-flags ''())
+                     (tests? #t)
+                     (phases '(@ (guix build node-build-system)
+                                 %standard-phases))
+                     (outputs '("out"))
+                     (search-paths '())
+                     (system (%current-system))
+                     (guile #f)
+                     (imported-modules %node-build-system-modules)
+                     (modules '((guix build node-build-system)
+				(guix build json)
+				(guix build union)
+                                (guix build utils))))
+  "Build SOURCE using NODE and INPUTS."
+  (define builder
+    `(begin
+       (use-modules ,@modules)
+       (node-build #:name ,name
+                   #:source ,(match (assoc-ref inputs "source")
+                               (((? derivation? source))
+                                (derivation->output-path source))
+                               ((source)
+                                source)
+                               (source
+                                source))
+                   #:system ,system
+                   #:npm-flags ,npm-flags
+                   #:tests? ,tests?
+                   #:phases ,phases
+                   #:outputs %outputs
+                   #:search-paths ',(map search-path-specification->sexp
+                                         search-paths)
+                   #:inputs %build-inputs)))
+
+  (define guile-for-build
+    (match guile
+      ((? package?)
+       (package-derivation store guile system #:graft? #f))
+      (#f
+       (let* ((distro (resolve-interface '(gnu packages commencement)))
+              (guile  (module-ref distro 'guile-final)))
+         (package-derivation store guile system #:graft? #f)))))
+
+  (build-expression->derivation store name builder
+                                #:inputs inputs
+                                #:system system
+                                #:modules imported-modules
+                                #:outputs outputs
+                                #:guile-for-build guile-for-build))
+
+(define node-build-system
+  (build-system
+    (name 'node)
+    (description "The standard Node build system")
+    (lower lower)))
diff --git a/guix/build/json.scm b/guix/build/json.scm
new file mode 100644
index 0000000000..361ea76728
--- /dev/null
+++ b/guix/build/json.scm
@@ -0,0 +1,387 @@
+;;;; json.scm --- JSON reader/writer
+;;;; Copyright (C) 2015 Free Software Foundation, Inc.
+;;;;
+;;;; This library is free software; you can redistribute it and/or
+;;;; modify it under the terms of the GNU Lesser General Public
+;;;; License as published by the Free Software Foundation; either
+;;;; version 3 of the License, or (at your option) any later version.
+;;;;
+;;;; This library is distributed in the hope that it will be useful,
+;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;;;; Lesser General Public License for more details.
+;;;;
+;;;; You should have received a copy of the GNU Lesser General Public
+;;;; License along with this library; if not, write to the Free Software
+;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+;;;;
+
+(define-module (guix build json)  ;; originally (ice-9 json)
+  #:use-module (ice-9 match)
+  #:export (read-json write-json))
+
+;; Snarfed from
+;; https://github.com/cwebber/activitystuff/blob/master/activitystuff/contrib/json.scm
+;; 
+
+;;;
+;;; Reader
+;;;
+
+(define (json-error port)
+  (throw 'json-error port))
+
+(define (assert-char port char)
+  "Read a character from PORT and throw an invalid JSON error if the
+character is not CHAR."
+  (unless (eqv? (read-char port) char)
+    (json-error port)))
+
+(define (whitespace? char)
+  "Return #t if CHAR is a whitespace character."
+  (char-set-contains? char-set:whitespace char))
+
+(define (consume-whitespace port)
+  "Discard characters from PORT until a non-whitespace character is
+encountered.."
+  (match (peek-char port)
+    ((? eof-object?) *unspecified*)
+    ((? whitespace?)
+     (read-char port)
+     (consume-whitespace port))
+    (_ *unspecified*)))
+
+(define (make-keyword-reader keyword value)
+  "Parse the keyword symbol KEYWORD as VALUE."
+  (let ((str (symbol->string keyword)))
+    (lambda (port)
+      (let loop ((i 0))
+        (cond
+         ((= i (string-length str)) value)
+         ((eqv? (string-ref str i) (read-char port))
+          (loop (1+ i)))
+         (else (json-error port)))))))
+
+(define read-true (make-keyword-reader 'true #t))
+(define read-false (make-keyword-reader 'false #f))
+(define read-null (make-keyword-reader 'null #nil))
+
+(define (read-hex-digit port)
+  "Read a hexadecimal digit from PORT."
+  (match (read-char port)
+    (#\0 0)
+    (#\1 1)
+    (#\2 2)
+    (#\3 3)
+    (#\4 4)
+    (#\5 5)
+    (#\6 6)
+    (#\7 7)
+    (#\8 8)
+    (#\9 9)
+    ((or #\A #\a) 10)
+    ((or #\B #\b) 11)
+    ((or #\C #\c) 12)
+    ((or #\D #\d) 13)
+    ((or #\E #\e) 14)
+    ((or #\F #\f) 15)
+    (_ (json-error port))))
+
+(define (read-utf16-character port)
+  "Read a hexadecimal encoded UTF-16 character from PORT."
+  (integer->char
+   (+ (* (read-hex-digit port) (expt 16 3))
+      (* (read-hex-digit port) (expt 16 2))
+      (* (read-hex-digit port) 16)
+      (read-hex-digit port))))
+
+(define (read-escape-character port)
+  "Read escape character from PORT."
+  (match (read-char port)
+    (#\" #\")
+    (#\\ #\\)
+    (#\/ #\/)
+    (#\b #\backspace)
+    (#\f #\page)
+    (#\n #\newline)
+    (#\r #\return)
+    (#\t #\tab)
+    (#\u (read-utf16-character port))
+    (_ (json-error port))))
+
+(define (read-string port)
+  "Read a JSON encoded string from PORT."
+  (assert-char port #\")
+  (let loop ((result '()))
+    (match (read-char port)
+      ((? eof-object?) (json-error port))
+      (#\" (list->string (reverse result)))
+      (#\\ (loop (cons (read-escape-character port) result)))
+      (char (loop (cons char result))))))
+
+(define char-set:json-digit
+  (char-set #\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7 #\8 #\9))
+
+(define (digit? char)
+  (char-set-contains? char-set:json-digit char))
+
+(define (read-digit port)
+  "Read a digit 0-9 from PORT."
+  (match (read-char port)
+    (#\0 0)
+    (#\1 1)
+    (#\2 2)
+    (#\3 3)
+    (#\4 4)
+    (#\5 5)
+    (#\6 6)
+    (#\7 7)
+    (#\8 8)
+    (#\9 9)
+    (else (json-error port))))
+
+(define (read-digits port)
+  "Read a sequence of digits from PORT."
+  (let loop ((result '()))
+    (match (peek-char port)
+      ((? eof-object?)
+       (reverse result))
+      ((? digit?)
+       (loop (cons (read-digit port) result)))
+      (else (reverse result)))))
+
+(define (list->integer digits)
+  "Convert the list DIGITS to an integer."
+  (let loop ((i (1- (length digits)))
+             (result 0)
+             (digits digits))
+    (match digits
+      (() result)
+      ((n . tail)
+       (loop (1- i)
+             (+ result (* n (expt 10 i)))
+             tail)))))
+
+(define (read-positive-integer port)
+  "Read a positive integer with no leading zeroes from PORT."
+  (match (read-digits port)
+    ((0 . _)
+     (json-error port)) ; no leading zeroes allowed
+    ((digits ...)
+     (list->integer digits))))
+
+(define (read-exponent port)
+  "Read exponent from PORT."
+  (define (read-expt)
+    (list->integer (read-digits port)))
+
+  (unless (memv (read-char port) '(#\e #\E))
+    (json-error port))
+
+  (match (peek-char port)
+    ((? eof-object?)
+     (json-error port))
+    (#\-
+     (read-char port)
+     (- (read-expt)))
+    (#\+
+     (read-char port)
+     (read-expt))
+    ((? digit?)
+     (read-expt))
+    (_ (json-error port))))
+
+(define (read-fraction port)
+  "Read fractional number part from PORT as an inexact number."
+  (let* ((digits      (read-digits port))
+         (numerator   (list->integer digits))
+         (denomenator (expt 10 (length digits))))
+    (/ numerator denomenator)))
+
+(define (read-positive-number port)
+  "Read a positive number from PORT."
+  (let* ((integer (match (peek-char port)
+                    ((? eof-object?)
+                     (json-error port))
+                    (#\0
+                     (read-char port)
+                     0)
+                    ((? digit?)
+                     (read-positive-integer port))
+                    (_ (json-error port))))
+         (fraction (match (peek-char port)
+                     (#\.
+                      (read-char port)
+                      (read-fraction port))
+                     (_ 0)))
+         (exponent (match (peek-char port)
+                     ((or #\e #\E)
+                      (read-exponent port))
+                     (_ 0)))
+         (n (* (+ integer fraction) (expt 10 exponent))))
+
+    ;; Keep integers as exact numbers, but convert numbers encoded as
+    ;; floating point numbers to an inexact representation.
+    (if (zero? fraction)
+        n
+        (exact->inexact n))))
+
+(define (read-number port)
+  "Read a number from PORT"
+  (match (peek-char port)
+    ((? eof-object?)
+     (json-error port))
+    (#\-
+     (read-char port)
+     (- (read-positive-number port)))
+    ((? digit?)
+     (read-positive-number port))
+    (_ (json-error port))))
+
+(define (read-object port)
+  "Read key/value map from PORT."
+  (define (read-key+value-pair)
+    (let ((key (read-string port)))
+      (consume-whitespace port)
+      (assert-char port #\:)
+      (consume-whitespace port)
+      (let ((value (read-value port)))
+        (cons key value))))
+
+  (assert-char port #\{)
+  (consume-whitespace port)
+
+  (if (eqv? #\} (peek-char port))
+      (begin
+        (read-char port)
+        '(@)) ; empty object
+      (let loop ((result (list (read-key+value-pair))))
+        (consume-whitespace port)
+        (match (peek-char port)
+          (#\, ; read another value
+           (read-char port)
+           (consume-whitespace port)
+           (loop (cons (read-key+value-pair) result)))
+          (#\} ; end of object
+           (read-char port)
+           (cons '@ (reverse result)))
+          (_ (json-error port))))))
+
+(define (read-array port)
+  "Read array from PORT."
+  (assert-char port #\[)
+  (consume-whitespace port)
+
+  (if (eqv? #\] (peek-char port))
+      (begin
+        (read-char port)
+        '()) ; empty array
+      (let loop ((result (list (read-value port))))
+        (consume-whitespace port)
+        (match (peek-char port)
+          (#\, ; read another value
+           (read-char port)
+           (consume-whitespace port)
+           (loop (cons (read-value port) result)))
+          (#\] ; end of array
+           (read-char port)
+           (reverse result))
+          (_ (json-error port))))))
+
+(define (read-value port)
+  "Read a JSON value from PORT."
+  (consume-whitespace port)
+  (match (peek-char port)
+    ((? eof-object?) (json-error port))
+    (#\" (read-string port))
+    (#\{ (read-object port))
+    (#\[ (read-array port))
+    (#\t (read-true port))
+    (#\f (read-false port))
+    (#\n (read-null port))
+    ((or #\- (? digit?))
+     (read-number port))
+    (_ (json-error port))))
+
+(define (read-json port)
+  "Read JSON text from port and return an s-expression representation."
+  (let ((result (read-value port)))
+    (consume-whitespace port)
+    (unless (eof-object? (peek-char port))
+      (json-error port))
+    result))
+
+
+;;;
+;;; Writer
+;;;
+
+(define (write-string str port)
+  "Write STR to PORT in JSON string format."
+  (define (escape-char char)
+    (display (match char
+               (#\" "\\\"")
+               (#\\ "\\\\")
+               (#\/ "\\/")
+               (#\backspace "\\b")
+               (#\page "\\f")
+               (#\newline "\\n")
+               (#\return "\\r")
+               (#\tab "\\t")
+               (_ char))
+             port))
+
+  (display "\"" port)
+  (string-for-each escape-char str)
+  (display "\"" port))
+
+(define (write-object alist port)
+  "Write ALIST to PORT in JSON object format."
+  ;; Keys may be strings or symbols.
+  (define key->string
+    (match-lambda
+     ((? string? key) key)
+     ((? symbol? key) (symbol->string key))))
+
+  (define (write-pair pair)
+    (match pair
+      ((key . value)
+       (write-string (key->string key) port)
+       (display ":" port)
+       (write-json value port))))
+
+  (display "{" port)
+  (match alist
+    (() #f)
+    ((front ... end)
+     (for-each (lambda (pair)
+                 (write-pair pair)
+                 (display "," port))
+          front)
+     (write-pair end)))
+  (display "}" port))
+
+(define (write-array lst port)
+  "Write LST to PORT in JSON array format."
+  (display "[" port)
+  (match lst
+    (() #f)
+    ((front ... end)
+     (for-each (lambda (val)
+                 (write-json val port)
+                 (display "," port))
+               front)
+     (write-json end port)))
+  (display "]" port))
+
+(define (write-json exp port)
+  "Write EXP to PORT in JSON format."
+  (match exp
+    (#t (display "true" port))
+    (#f (display "false" port))
+    ;; Differentiate #nil from '().
+    ((and (? boolean? ) #nil) (display "null" port))
+    ((? string? s) (write-string s port))
+    ((? real? n) (display n port))
+    (('@ . alist) (write-object alist port))
+    ((vals ...) (write-array vals port))))
diff --git a/guix/build/node-build-system.scm b/guix/build/node-build-system.scm
new file mode 100644
index 0000000000..201664c5c1
--- /dev/null
+++ b/guix/build/node-build-system.scm
@@ -0,0 +1,164 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2015 David Thompson <[email-masked]>
+;;; Copyright © 2016 Jelle Licht <[email-masked]>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (guix build node-build-system)
+  #:use-module ((guix build gnu-build-system) #:prefix gnu:)
+  #:use-module (guix build json)
+  #:use-module (guix build union)
+  #:use-module (guix build utils)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 popen)
+  #:use-module (ice-9 regex)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+  #:export (%standard-phases
+            node-build))
+
+;; Commentary:
+;;
+;; Builder-side code of the standard Node/npm package build procedure.
+;;
+;; Code:
+
+(define* (read-package-data #:key (filename "package.json"))
+  (call-with-input-file filename
+    (lambda (port)
+      (read-json port))))
+
+(define* (build #:key inputs #:allow-other-keys)
+  (define (build-from-package-json? package-file)
+    (let* ((package-data (read-package-data #:filename package-file))
+           (scripts (assoc-ref package-data "scripts")))
+      (assoc-ref scripts "build")))
+  "Build a new node module using the appropriate build system."
+  ;; XXX: Develop a more robust heuristic, allow override
+  (cond ((file-exists? "gulpfile.js")
+         (invoke "gulp"))
+        ((file-exists? "gruntfile.js")
+         (invoke "grunt"))
+        ((file-exists? "Makefile")
+         (invoke "make"))
+        ((and (file-exists? "package.json")
+              (build-from-package-json? "package.json"))
+         (invoke "npm" "run" "build")))
+  #t)
+
+(define* (link-npm-dependencies #:key inputs #:allow-other-keys)
+  (define (inputs->node-inputs inputs)
+    "Filter the directory part from INPUTS."
+    (filter (lambda (input)
+              (match input
+                ((name . _) (node-package? name))))
+            inputs))
+  (define (inputs->directories inputs)
+    "Extract the directory part from INPUTS."
+    (match inputs
+      (((names . directories) ...)
+       directories)))
+  (define (make-node-path root)
+    (string-append root "/lib/node_modules/"))
+
+  (let ((input-node-directories (inputs->directories
+                                 (inputs->node-inputs inputs))))
+    (union-build "node_modules"
+                 (map make-node-path input-node-directories))
+    #t))
+
+(define configure link-npm-dependencies)
+
+(define* (check #:key tests? #:allow-other-keys)
+  "Run 'npm test' if TESTS?"
+  (if tests?
+      ;; Should only be enabled once we know that there are tests
+      (invoke "npm" "test"))
+  #t)
+
+(define (node-package? name)
+  "Check if NAME correspond to the name of an Node package."
+  (string-prefix? "node-" name))
+
+(define* (install #:key outputs inputs #:allow-other-keys)
+  "Install the node module to the output store item. MODULENAME defines
+under which name the module will be installed, GLOBAL? determines whether this
+is an npm global install."
+  (let* ((out                  (assoc-ref outputs "out"))
+         (target               (string-append out "/lib"))
+         (binaries             (string-append out "/bin"))
+         (data                 (read-package-data))
+         (modulename           (assoc-ref data "name"))
+         (binary-configuration (match (assoc-ref data "bin")
+				 (('@ configuration ...) configuration)
+				 ((? string? configuration) configuration)
+				 (#f #f)))
+         (dependencies (match (assoc-ref data "dependencies")
+                         (('@ deps ...) deps)
+                         (#f #f))))
+    (mkdir-p target)
+    (copy-recursively "." (string-append target "/node_modules/" modulename))
+    ;; Remove references to dependencies
+    (delete-file-recursively
+      (string-append target "/node_modules/" modulename "/node_modules"))
+    (cond
+      ((string? binary-configuration)
+       (begin
+         (mkdir-p binaries)
+         (symlink (string-append target "/node_modules/" modulename "/"
+				 binary-configuration)
+                  (string-append binaries "/" modulename))))
+      ((list? binary-configuration)
+       (for-each
+         (lambda (conf)
+           (match conf
+             ((key . value)
+              (begin
+                (mkdir-p (dirname (string-append binaries "/" key)))
+                (symlink (string-append target "/node_modules/" modulename "/"
+					value)
+                         (string-append binaries "/" key))))))
+         binary-configuration))
+      (else
+        (symlink (string-append target "/node_modules/" modulename "/bin")
+		 binaries)))
+    (when dependencies
+      (mkdir-p
+        (string-append target "/node_modules/" modulename "/node_modules"))
+      (for-each
+        (lambda (dependency)
+          (let ((dependency (car dependency)))
+            (symlink
+              (string-append (assoc-ref inputs (string-append "node-" dependency))
+                             "/lib/node_modules/" dependency)
+              (string-append target "/node_modules/" modulename
+                             "/node_modules/" dependency))))
+        dependencies))
+    #t))
+
+
+(define %standard-phases
+  (modify-phases gnu:%standard-phases
+    (replace 'configure configure)
+    (replace 'build build)
+    (replace 'install install)
+    (delete 'check)
+    (add-after 'install 'check check)
+    (delete 'strip)))
+
+(define* (node-build #:key inputs (phases %standard-phases)
+                     #:allow-other-keys #:rest args)
+  (apply gnu:gnu-build #:inputs inputs #:phases phases args))
-- 
2.22.0