diff mbox series

[bug#38408,v9,2/8] guix: import: crate: Use semver to resovle module versions

Message ID 7dbe9a73fe56e1116d3207ef3cb9547a32b9a773.1580817140.git.mjbecze@riseup.net
State Accepted
Headers show
Series recursive semver crate importer! | expand

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Commit Message

Martin Becze Feb. 4, 2020, 12:18 p.m. UTC 
*  guix/import/crate.scm (make-crate-sexp): formatting, added '#:skip-build?'
   to build system args; added package definition geneation
*  guix/import/crate.scm (crate->guix-package): Use semver to resolve the
   correct module versions
*  tests/crate.scm: added version data to (recursuve-import) test
---
 guix/import/crate.scm         |  87 ++++++----
 guix/scripts/import/crate.scm |  11 +-
 tests/crate.scm               | 290 +++++++++++++++++++---------------
 3 files changed, 225 insertions(+), 163 deletions(-)

Comments

Ludovic Courtès Feb. 17, 2020, 2:35 p.m. UTC | #1 
Hi Martin & Efraim,

Thinking more about it, I’m not sure I fully understand why we need to
pay attention to semver here:

Martin Becze <mjbecze@riseup.net> skribis:

> +(define* (crate->guix-package crate-name #:key version #:allow-other-keys)
>    "Fetch the metadata for CRATE-NAME from crates.io, and return the
>  `package' s-expression corresponding to that package, or #f on failure.
>  When VERSION is specified, attempt to fetch that version; otherwise fetch the
>  latest version of CRATE-NAME."
>  
> +  (define (semver-range-contains-string? range version)
> +    (semver-range-contains? (string->semver-range range)
> +                            (string->semver version)))
> +
>    (define (normal-dependency? dependency)
> -    (eq? (crate-dependency-kind dependency) 'normal))
> +    (or (eq? (crate-dependency-kind dependency) 'build)
> +        (eq? (crate-dependency-kind dependency) 'normal)))
>  
>    (define crate
>      (lookup-crate crate-name))
> @@ -204,21 +218,36 @@ latest version of CRATE-NAME."
>      (or version
>          (crate-latest-version crate)))
>  
> -  (define version*
> +  (define (find-version crate range)
> +    "finds the a vesion of a crate that fulfils the semver <range>"
>      (find (lambda (version)
> -            (string=? (crate-version-number version)
> -                      version-number))
> +            (semver-range-contains-string?
> +             range
> +             (crate-version-number version)))
>            (crate-versions crate)))

The reason I wonder is that the HTTP API gives us rather precise
dependency requirements:

--8<---------------cut here---------------start------------->8---
scheme@(guix import crate)> (crate-version-dependencies (car (crate-versions (lookup-crate "blake2-rfc"))))
$8 = (#<<crate-dependency> id: "arrayvec" kind: normal requirement: "^0.4.6"> #<<crate-dependency> id: "constant_time_eq" kind: normal requirement: "^0.1.0"> #<<crate-dependency> id: "data-encoding" kind: dev requirement: "^2.0.0"> #<<crate-dependency> id: "clippy" kind: normal requirement: "^0.0.41">)
--8<---------------cut here---------------end--------------->8---

In the example above, the importer could “just” fetch version 0.4.6 of
arrayvec, version 0.1.0 of constant_time_eq, etc., no?

It’s an approximation because the caret (^) means more than just this,
but hopefully it’s a good approximation.

Am I missing something?

Ludo’.
Efraim Flashner Feb. 17, 2020, 2:57 p.m. UTC | #2 
On Mon, Feb 17, 2020 at 03:35:20PM +0100, Ludovic Courtès wrote:
> Hi Martin & Efraim,
> 
> Thinking more about it, I’m not sure I fully understand why we need to
> pay attention to semver here:
> 
> Martin Becze <mjbecze@riseup.net> skribis:
> 
> > +(define* (crate->guix-package crate-name #:key version #:allow-other-keys)
> >    "Fetch the metadata for CRATE-NAME from crates.io, and return the
> >  `package' s-expression corresponding to that package, or #f on failure.
> >  When VERSION is specified, attempt to fetch that version; otherwise fetch the
> >  latest version of CRATE-NAME."
> >  
> > +  (define (semver-range-contains-string? range version)
> > +    (semver-range-contains? (string->semver-range range)
> > +                            (string->semver version)))
> > +
> >    (define (normal-dependency? dependency)
> > -    (eq? (crate-dependency-kind dependency) 'normal))
> > +    (or (eq? (crate-dependency-kind dependency) 'build)
> > +        (eq? (crate-dependency-kind dependency) 'normal)))
> >  
> >    (define crate
> >      (lookup-crate crate-name))
> > @@ -204,21 +218,36 @@ latest version of CRATE-NAME."
> >      (or version
> >          (crate-latest-version crate)))
> >  
> > -  (define version*
> > +  (define (find-version crate range)
> > +    "finds the a vesion of a crate that fulfils the semver <range>"
> >      (find (lambda (version)
> > -            (string=? (crate-version-number version)
> > -                      version-number))
> > +            (semver-range-contains-string?
> > +             range
> > +             (crate-version-number version)))
> >            (crate-versions crate)))
> 
> The reason I wonder is that the HTTP API gives us rather precise
> dependency requirements:
> 
> --8<---------------cut here---------------start------------->8---
> scheme@(guix import crate)> (crate-version-dependencies (car (crate-versions (lookup-crate "blake2-rfc"))))
> $8 = (#<<crate-dependency> id: "arrayvec" kind: normal requirement: "^0.4.6"> #<<crate-dependency> id: "constant_time_eq" kind: normal requirement: "^0.1.0"> #<<crate-dependency> id: "data-encoding" kind: dev requirement: "^2.0.0"> #<<crate-dependency> id: "clippy" kind: normal requirement: "^0.0.41">)
> --8<---------------cut here---------------end--------------->8---
> 
> In the example above, the importer could “just” fetch version 0.4.6 of
> arrayvec, version 0.1.0 of constant_time_eq, etc., no?
> 
> It’s an approximation because the caret (^) means more than just this,
> but hopefully it’s a good approximation.
> 
> Am I missing something?
> 
> Ludo’.

Here we're looking at a minimum of 0.4.6 for arrayvec. According to
here¹ we'd really want to import 0.4.12, which is the latest 0.4.x
release.

¹ https://crates.io/crates/arrayvec/versions
Ludovic Courtès Feb. 17, 2020, 3:37 p.m. UTC | #3 
Efraim Flashner <efraim@flashner.co.il> skribis:

> On Mon, Feb 17, 2020 at 03:35:20PM +0100, Ludovic Courtès wrote:

[...]

>> --8<---------------cut here---------------start------------->8---
>> scheme@(guix import crate)> (crate-version-dependencies (car (crate-versions (lookup-crate "blake2-rfc"))))
>> $8 = (#<<crate-dependency> id: "arrayvec" kind: normal requirement: "^0.4.6"> #<<crate-dependency> id: "constant_time_eq" kind: normal requirement: "^0.1.0"> #<<crate-dependency> id: "data-encoding" kind: dev requirement: "^2.0.0"> #<<crate-dependency> id: "clippy" kind: normal requirement: "^0.0.41">)
>> --8<---------------cut here---------------end--------------->8---
>> 
>> In the example above, the importer could “just” fetch version 0.4.6 of
>> arrayvec, version 0.1.0 of constant_time_eq, etc., no?
>> 
>> It’s an approximation because the caret (^) means more than just this,
>> but hopefully it’s a good approximation.
>> 
>> Am I missing something?
>> 
>> Ludo’.
>
> Here we're looking at a minimum of 0.4.6 for arrayvec. According to
> here¹ we'd really want to import 0.4.12, which is the latest 0.4.x
> release.

That’s why I wrote that 0.4.6 is an approximation (probably a good one
because it’s apparently known to work.)

We can do something smarter, but then it’s only useful if the updater is
equally smart—that is, it can update 0.4.6 to 0.4.13 whenever that
version is out, knowing that blake2-rfc will still work fine.

Tricky!  WDYT?

Ludo’.
Martin Becze Feb. 18, 2020, 8:56 a.m. UTC | #4 
On 2/17/20 10:37 AM, Ludovic Courtès wrote:
> That’s why I wrote that 0.4.6 is an approximation (probably a good one
> because it’s apparently known to work.)

Just grabbing the version from the semver range would work for some 
ranage would break on Hyphenated ranges (1.2.3 - 2), Combining ranges 
(>=0.14 <16) and on the asterisk range operator (1.*.* or 2.*)

Currently we are just trying to pick the most recent version that fits 
in the semver range.

> We can do something smarter, but then it’s only useful if the updater is
> equally smart—that is, it can update 0.4.6 to 0.4.13 whenever that
> version is out, knowing that blake2-rfc will still work fine.

Yep argeed! I would like to fix the updater as well, but i thought i 
should wait to send that in after this one gets in. Also it can quickly 
turns in to a SAT problem. I think we have two basic options though.

1) update everything to the newest possible version (easiest and this is 
what the importer does currently)

2) make the smallest possible dependency graph for all packages (harder, 
involves a SAT solver)
diff mbox series

Patch

diff --git a/guix/import/crate.scm b/guix/import/crate.scm
index 57823c3639..84b152620c 100644
--- a/guix/import/crate.scm
+++ b/guix/import/crate.scm
@@ -1,7 +1,7 @@ 
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2016 David Craven <david@craven.ch>
 ;;; Copyright © 2019, 2020 Ludovic Courtès <ludo@gnu.org>
-;;; Copyright © 2019 Martin Becze <mjbecze@riseup.net>
+;;; Copyright © 2019, 2020 Martin Becze <mjbecze@riseup.net>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -35,9 +35,12 @@ 
   #:use-module (ice-9 match)
   #:use-module (ice-9 regex)
   #:use-module (json)
+  #:use-module (semver)
+  #:use-module (semver ranges)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-2)
   #:use-module (srfi srfi-26)
+  #:use-module (srfi srfi-71)
   #:export (crate->guix-package
             guix-package->crate-name
             string->license
@@ -86,7 +89,7 @@ 
   crate-dependency?
   json->crate-dependency
   (id            crate-dependency-id "crate_id")  ;string
-  (kind          crate-dependency-kind "kind"     ;'normal | 'dev
+  (kind          crate-dependency-kind "kind"     ;'normal | 'dev | 'build
                  string->symbol)
   (requirement   crate-dependency-requirement "req")) ;string
 
@@ -150,9 +153,14 @@  VERSION, CARGO-INPUTS, CARGO-DEVELOPMENT-INPUTS, HOME-PAGE, SYNOPSIS, DESCRIPTIO
 and LICENSE."
   (let* ((port (http-fetch (crate-uri name version)))
          (guix-name (crate-name->package-name name))
-         (cargo-inputs (map crate-name->package-name cargo-inputs))
-         (cargo-development-inputs (map crate-name->package-name
-                                        cargo-development-inputs))
+         (cargo-inputs
+          (map
+           (lambda (name-version)
+             (apply crate-name->package-name name-version)) cargo-inputs))
+         (cargo-development-inputs
+          (map
+           (lambda (name-version)
+             (apply crate-name->package-name name-version)) cargo-development-inputs))
          (pkg `(package
                    (name ,guix-name)
                    (version ,version)
@@ -164,9 +172,10 @@  and LICENSE."
                               (base32
                                ,(bytevector->nix-base32-string (port-sha256 port))))))
                    (build-system cargo-build-system)
-                   ,@(maybe-arguments (append (maybe-cargo-inputs cargo-inputs)
+                   ,@(maybe-arguments (append '(#:skip-build? #t)
+                                              (maybe-cargo-inputs cargo-inputs)
                                               (maybe-cargo-development-inputs
-                                                cargo-development-inputs)))
+                                               cargo-development-inputs)))
                    (home-page ,(match home-page
                                  (() "")
                                  (_ home-page)))
@@ -177,7 +186,7 @@  and LICENSE."
                                ((license) license)
                                (_ `(list ,@license)))))))
          (close-port port)
-         pkg))
+         (package->definition pkg #t)))
 
 (define (string->license string)
   (filter-map (lambda (license)
@@ -188,14 +197,19 @@  and LICENSE."
                          'unknown-license!)))
               (string-split string (string->char-set " /"))))
 
-(define* (crate->guix-package crate-name #:optional version)
+(define* (crate->guix-package crate-name #:key version #:allow-other-keys)
   "Fetch the metadata for CRATE-NAME from crates.io, and return the
 `package' s-expression corresponding to that package, or #f on failure.
 When VERSION is specified, attempt to fetch that version; otherwise fetch the
 latest version of CRATE-NAME."
 
+  (define (semver-range-contains-string? range version)
+    (semver-range-contains? (string->semver-range range)
+                            (string->semver version)))
+
   (define (normal-dependency? dependency)
-    (eq? (crate-dependency-kind dependency) 'normal))
+    (or (eq? (crate-dependency-kind dependency) 'build)
+        (eq? (crate-dependency-kind dependency) 'normal)))
 
   (define crate
     (lookup-crate crate-name))
@@ -204,21 +218,36 @@  latest version of CRATE-NAME."
     (or version
         (crate-latest-version crate)))
 
-  (define version*
+  (define (find-version crate range)
+    "finds the a vesion of a crate that fulfils the semver <range>"
     (find (lambda (version)
-            (string=? (crate-version-number version)
-                      version-number))
+            (semver-range-contains-string?
+             range
+             (crate-version-number version)))
           (crate-versions crate)))
 
+  (define version*
+    (find-version crate version-number))
+
+  (define (sort-map-deps deps)
+    "sorts the dependencies and maps the dependencies to a list
+     containing pairs of (name version)"
+    (sort (map (lambda (dep)
+                 (let* ((name (crate-dependency-id dep))
+                        (crate (lookup-crate name))
+                        (req (crate-dependency-requirement dep))
+                        (ver (find-version crate req)))
+                   (list name
+                         (crate-version-number ver))))
+               deps)
+          (match-lambda* (((_ name) ...)
+                          (apply string-ci<? name)))))
+
   (and crate version*
-       (let* ((dependencies   (crate-version-dependencies version*))
-              (dep-crates     (filter normal-dependency? dependencies))
-              (dev-dep-crates (remove normal-dependency? dependencies))
-              (cargo-inputs   (sort (map crate-dependency-id dep-crates)
-                                    string-ci<?))
-              (cargo-development-inputs
-               (sort (map crate-dependency-id dev-dep-crates)
-                     string-ci<?)))
+       (let* ((dependencies (crate-version-dependencies version*))
+              (dep-crates dev-dep-crates (partition normal-dependency? dependencies))
+              (cargo-inputs (sort-map-deps dep-crates))
+              (cargo-development-inputs '()))
          (values
           (make-crate-sexp #:name crate-name
                            #:version (crate-version-number version*)
@@ -230,15 +259,12 @@  latest version of CRATE-NAME."
                            #:description (crate-description crate)
                            #:license (and=> (crate-version-license version*)
                                             string->license))
-          (append cargo-inputs cargo-development-inputs)))))
+          cargo-inputs))))
 
-(define* (crate-recursive-import crate-name #:optional version)
-  (recursive-import crate-name #f
-                    #:repo->guix-package
-                    (lambda (name repo)
-                      (let ((version (and (string=? name crate-name)
-                                          version)))
-                        (crate->guix-package name version)))
+(define* (crate-recursive-import crate-name #:key version)
+  (recursive-import crate-name
+                    #:repo->guix-package crate->guix-package
+                    #:version version
                     #:guix-name crate-name->package-name))
 
 (define (guix-package->crate-name package)
@@ -253,7 +279,7 @@  latest version of CRATE-NAME."
       ((name _ ...) name))))
 
 (define (crate-name->package-name name)
-  (string-append "rust-" (string-join (string-split name #\_) "-")))
+  (guix-name "rust-" name))
 
 
 ;;;
@@ -288,4 +314,3 @@  latest version of CRATE-NAME."
    (description "Updater for crates.io packages")
    (pred crate-package?)
    (latest latest-release)))
-
diff --git a/guix/scripts/import/crate.scm b/guix/scripts/import/crate.scm
index d834518c18..552628cfc7 100644
--- a/guix/scripts/import/crate.scm
+++ b/guix/scripts/import/crate.scm
@@ -2,7 +2,7 @@ 
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2014 David Thompson <davet@gnu.org>
 ;;; Copyright © 2016 David Craven <david@craven.ch>
-;;; Copyright © 2019 Martin Becze <mjbecze@riseup.net>
+;;; Copyright © 2019, 2020 Martin Becze <mjbecze@riseup.net>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -95,13 +95,8 @@  Import and convert the crate.io package for PACKAGE-NAME.\n"))
          (package-name->name+version spec))
 
        (if (assoc-ref opts 'recursive)
-           (map (match-lambda
-                  ((and ('package ('name name) . rest) pkg)
-                   `(define-public ,(string->symbol name)
-                      ,pkg))
-                  (_ #f))
-                (crate-recursive-import name version))
-           (let ((sexp (crate->guix-package name version)))
+           (crate-recursive-import name #:version version)
+           (let ((sexp (crate->guix-package name #:version version)))
              (unless sexp
                (leave (G_ "failed to download meta-data for package '~a'~%")
                       (if version
diff --git a/tests/crate.scm b/tests/crate.scm
index aa51faebf9..39561d5745 100644
--- a/tests/crate.scm
+++ b/tests/crate.scm
@@ -2,6 +2,7 @@ 
 ;;; Copyright © 2014 David Thompson <davet@gnu.org>
 ;;; Copyright © 2016 David Craven <david@craven.ch>
 ;;; Copyright © 2019, 2020 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2020 Martin Becze <mjbecze@riseup.net>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -54,8 +55,9 @@ 
   "{
   \"dependencies\": [
      {
-       \"crate_id\": \"bar\",
+       \"crate_id\": \"leaf-alice\",
        \"kind\": \"normal\",
+       \"req\": \"1.0.0\",
      }
   ]
 }")
@@ -88,18 +90,22 @@ 
      {
        \"crate_id\": \"intermediate-1\",
        \"kind\": \"normal\",
+       \"req\": \"1.0.0\",
      },
      {
        \"crate_id\": \"intermediate-2\",
        \"kind\": \"normal\",
+       \"req\": \"1.0.0\",
      }
      {
        \"crate_id\": \"leaf-alice\",
        \"kind\": \"normal\",
+       \"req\": \"1.0.0\",
      },
      {
        \"crate_id\": \"leaf-bob\",
        \"kind\": \"normal\",
+       \"req\": \"1.0.0\",
      },
   ]
 }")
@@ -132,14 +138,17 @@ 
      {
        \"crate_id\": \"intermediate-2\",
        \"kind\": \"normal\",
+       \"req\": \"1.0.0\",
      },
      {
        \"crate_id\": \"leaf-alice\",
        \"kind\": \"normal\",
+       \"req\": \"1.0.0\",
      },
      {
        \"crate_id\": \"leaf-bob\",
        \"kind\": \"normal\",
+       \"req\": \"1.0.0\",
      }
   ]
 }")
@@ -172,6 +181,7 @@ 
      {
        \"crate_id\": \"leaf-bob\",
        \"kind\": \"normal\",
+       \"req\": \"1.0.0\",
      },
   ]
 }")
@@ -252,34 +262,48 @@ 
               (open-input-string test-foo-crate))
              ("https://crates.io/api/v1/crates/foo/1.0.0/download"
               (set! test-source-hash
-                (bytevector->nix-base32-string
-                 (sha256 (string->bytevector "empty file\n" "utf-8"))))
+                    (bytevector->nix-base32-string
+                     (sha256 (string->bytevector "empty file\n" "utf-8"))))
               (open-input-string "empty file\n"))
              ("https://crates.io/api/v1/crates/foo/1.0.0/dependencies"
               (open-input-string test-foo-dependencies))
+             ("https://crates.io/api/v1/crates/leaf-alice"
+              (open-input-string test-leaf-alice-crate))
+             ("https://crates.io/api/v1/crates/leaf-alice/1.0.0/download"
+              (set! test-source-hash
+                    (bytevector->nix-base32-string
+                     (sha256 (string->bytevector "empty file\n" "utf-8"))))
+              (open-input-string "empty file\n"))
+             ("https://crates.io/api/v1/crates/leaf-alice/1.0.0/dependencies"
+              (open-input-string test-leaf-alice-dependencies))
              (_ (error "Unexpected URL: " url)))))
-    (match (crate->guix-package "foo")
-      (('package
-         ('name "rust-foo")
-         ('version "1.0.0")
-         ('source ('origin
-                    ('method 'url-fetch)
-                    ('uri ('crate-uri "foo" 'version))
-                    ('file-name ('string-append 'name "-" 'version ".tar.gz"))
-                    ('sha256
-                     ('base32
-                      (? string? hash)))))
-         ('build-system 'cargo-build-system)
-         ('arguments
-          ('quasiquote
-           ('#:cargo-inputs (("rust-bar" ('unquote rust-bar))))))
-         ('home-page "http://example.com")
-         ('synopsis "summary")
-         ('description "summary")
-         ('license ('list 'license:expat 'license:asl2.0)))
-       (string=? test-source-hash hash))
-      (x
-       (pk 'fail x #f)))))
+
+        (match (crate->guix-package "foo")
+          ((define-public rust-foo-1.0.0
+             (package (name "rust-foo")
+                      (version "1.0.0")
+                      (source
+                       (origin
+                         (method url-fetch)
+                         (uri (crate-uri "foo" 'version))
+                         (file-name (string-append name "-" version ".tar.gz"))
+                         (sha256
+                          (base32
+                           (?  string? hash)))))
+                      (build-system 'cargo-build-system)
+                      (arguments
+                       ('quasiquote
+                        (#:skip-build? #t
+                         #:cargo-inputs
+                         (("rust-leaf-alice-1.0.0" ('unquote rust-leaf-alice-1.0.0))))))
+                      (home-page "http://example.com")
+                      (synopsis "summary")
+                      (description "summary")
+                      (license (list license:expat license:asl2.0))))
+
+           (string=? test-source-hash hash))
+          (x
+           (pk 'fail x #f)))))
 
 (test-assert "cargo-recursive-import"
   ;; Replace network resources with sample data.
@@ -334,105 +358,123 @@ 
              (_ (error "Unexpected URL: " url)))))
         (match (crate-recursive-import "root")
           ;; rust-intermediate-2 has no dependency on the rust-leaf-alice package, so this is a valid ordering
-          ((('package
-              ('name "rust-leaf-alice")
-              ('version (? string? ver))
-              ('source
-               ('origin
-                 ('method 'url-fetch)
-                 ('uri ('crate-uri "leaf-alice" 'version))
-                 ('file-name
-                  ('string-append 'name "-" 'version ".tar.gz"))
-                 ('sha256
-                  ('base32
-                   (? string? hash)))))
-              ('build-system 'cargo-build-system)
-              ('home-page "http://example.com")
-              ('synopsis "summary")
-              ('description "summary")
-              ('license ('list 'license:expat 'license:asl2.0)))
-            ('package
-              ('name "rust-leaf-bob")
-              ('version (? string? ver))
-              ('source
-               ('origin
-                 ('method 'url-fetch)
-                 ('uri ('crate-uri "leaf-bob" 'version))
-                 ('file-name
-                  ('string-append 'name "-" 'version ".tar.gz"))
-                 ('sha256
-                  ('base32
-                   (? string? hash)))))
-              ('build-system 'cargo-build-system)
-              ('home-page "http://example.com")
-              ('synopsis "summary")
-              ('description "summary")
-              ('license ('list 'license:expat 'license:asl2.0)))
-            ('package
-              ('name "rust-intermediate-2")
-              ('version (? string? ver))
-              ('source
-               ('origin
-                 ('method 'url-fetch)
-                 ('uri ('crate-uri "intermediate-2" 'version))
-                 ('file-name
-                  ('string-append 'name "-" 'version ".tar.gz"))
-                 ('sha256
-                  ('base32
-                   (? string? hash)))))
-              ('build-system 'cargo-build-system)
-              ('arguments
-               ('quasiquote
-                ('#:cargo-inputs (("rust-leaf-bob" ('unquote rust-leaf-bob))))))
-              ('home-page "http://example.com")
-              ('synopsis "summary")
-              ('description "summary")
-              ('license ('list 'license:expat 'license:asl2.0)))
-            ('package
-              ('name "rust-intermediate-1")
-              ('version (? string? ver))
-              ('source
-               ('origin
-                 ('method 'url-fetch)
-                 ('uri ('crate-uri "intermediate-1" 'version))
-                 ('file-name
-                  ('string-append 'name "-" 'version ".tar.gz"))
-                 ('sha256
-                  ('base32
-                   (? string? hash)))))
-              ('build-system 'cargo-build-system)
-              ('arguments
-               ('quasiquote
-                ('#:cargo-inputs (("rust-intermediate-2" ('unquote rust-intermediate-2))
-                                  ("rust-leaf-alice" ('unquote rust-leaf-alice))
-                                  ("rust-leaf-bob" ('unquote rust-leaf-bob))))))
-              ('home-page "http://example.com")
-              ('synopsis "summary")
-              ('description "summary")
-              ('license ('list 'license:expat 'license:asl2.0)))
-            ('package
-              ('name "rust-root")
-              ('version (? string? ver))
-              ('source
-               ('origin
-                 ('method 'url-fetch)
-                 ('uri ('crate-uri "root" 'version))
-                 ('file-name
-                  ('string-append 'name "-" 'version ".tar.gz"))
-                 ('sha256
-                  ('base32
-                   (? string? hash)))))
-              ('build-system 'cargo-build-system)
-              ('arguments
-               ('quasiquote
-                ('#:cargo-inputs (("rust-intermediate-1" ('unquote rust-intermediate-1))
-                                  ("rust-intermediate-2" ('unquote rust-intermediate-2))
-                                  ("rust-leaf-alice" ('unquote rust-leaf-alice))
-                                  ("rust-leaf-bob" ('unquote rust-leaf-bob))))))
-              ('home-page "http://example.com")
-              ('synopsis "summary")
-              ('description "summary")
-              ('license ('list 'license:expat 'license:asl2.0))))
+          (((define-public rust-leaf-alice-1.0.0
+              (package
+                (name "rust-leaf-alice")
+                (version (?  string? ver))
+                (source
+                 (origin
+                   (method url-fetch)
+                   (uri (crate-uri "leaf-alice" version))
+                   (file-name
+                    (string-append name "-" version ".tar.gz"))
+                   (sha256
+                    (base32
+                     (?  string? hash)))))
+                (build-system cargo-build-system)
+                (arguments ('quasiquote (#:skip-build? #t)))
+                (home-page "http://example.com")
+                (synopsis "summary")
+                (description "summary")
+                (license (list license:expat license:asl2.0))))
+            (define-public rust-leaf-bob-1.0.0
+              (package
+                (name "rust-leaf-bob")
+                (version (?  string? ver))
+                (source
+                 (origin
+                   (method url-fetch)
+                   (uri (crate-uri "leaf-bob" version))
+                   (file-name
+                    (string-append name "-" version ".tar.gz"))
+                   (sha256
+                    (base32
+                     (?  string? hash)))))
+                (build-system cargo-build-system)
+                (arguments ('quasiquote (#:skip-build? #t)))
+                (home-page "http://example.com")
+                (synopsis "summary")
+                (description "summary")
+                (license (list license:expat license:asl2.0))))
+            (define-public rust-intermediate-2-1.0.0
+              (package
+                (name "rust-intermediate-2")
+                (version (?  string? ver))
+                (source
+                 (origin
+                   (method url-fetch)
+                   (uri (crate-uri "intermediate-2" version))
+                   (file-name
+                    (string-append name "-" version ".tar.gz"))
+                   (sha256
+                    (base32
+                     (?  string? hash)))))
+                (build-system cargo-build-system)
+                (arguments
+                 ('quasiquote (#:skip-build? #t
+                               #:cargo-inputs
+                               (("rust-leaf-bob-1.0.0"
+                                 ('unquote rust-leaf-bob-1.0.0))))))
+                (home-page "http://example.com")
+                (synopsis "summary")
+                (description "summary")
+                (license (list license:expat license:asl2.0))))
+            (define-public rust-intermediate-1-1.0.0
+              (package
+                (name "rust-intermediate-1")
+                (version (?  string? ver))
+                (source
+                 (origin
+                   (method url-fetch)
+                   (uri (crate-uri "intermediate-1" version))
+                   (file-name
+                    (string-append name "-" version ".tar.gz"))
+                   (sha256
+                    (base32
+                     (?  string? hash)))))
+                (build-system cargo-build-system)
+                (arguments
+                 ('quasiquote (#:skip-build? #t
+                               #:cargo-inputs
+                               (("rust-intermediate-2-1.0.0"
+                                 ,rust-intermediate-2-1.0.0)
+                                ("rust-leaf-alice-1.0.0"
+                                 ('unquote rust-leaf-alice-1.0.0))
+                                ("rust-leaf-bob-1.0.0"
+                                 ('unquote rust-leaf-bob-1.0.0))))))
+                (home-page "http://example.com")
+                (synopsis "summary")
+                (description "summary")
+                (license (list license:expat license:asl2.0))))
+            (define-public rust-root-1.0.0
+              (package
+                (name "rust-root")
+                (version (?  string? ver))
+                (source
+                 (origin
+                   (method url-fetch)
+                   (uri (crate-uri "root" version))
+                   (file-name
+                    (string-append name "-" version ".tar.gz"))
+                   (sha256
+                    (base32
+                     (?  string? hash)))))
+                (build-system cargo-build-system)
+                (arguments
+                 ('quasiquote (#:skip-build?
+                               #t #:cargo-inputs
+                               (("rust-intermediate-1-1.0.0"
+                                 ('unquote rust-intermediate-1-1.0.0))
+                                ("rust-intermediate-2-1.0.0"
+                                 ('unquote rust-intermediate-2-1.0.0))
+                                ("rust-leaf-alice-1.0.0"
+                                 ('unquote rust-leaf-alice-1.0.0))
+                                ("rust-leaf-bob-1.0.0"
+                                 ('unquote rust-leaf-bob-1.0.0))))))
+                (home-page "http://example.com")
+                (synopsis "summary")
+                (description "summary")
+                (license (list license:expat license:asl2.0)))))
            #t)
           (x
            (pk 'fail x #f)))))