diff --git a/Makefile.am b/Makefile.am
index a60542e..4c68c04 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -29,24 +29,25 @@ moddir = $(prefix)/share/guile/site/$(GUILE_EFFECTIVE_VERSION)
 godir  = $(moddir)
 assetsdir = $(datadir)/@PACKAGE@
 
-SOURCES =						\
-  guix-data-service/builds.scm				\
-  guix-data-service/comparison.scm			\
-  guix-data-service/config.scm				\
-  guix-data-service/jobs.scm				\
-  guix-data-service/jobs/load-new-guix-revision.scm	\
-  guix-data-service/model/build-server.scm		\
-  guix-data-service/model/build-status.scm		\
-  guix-data-service/model/build.scm			\
-  guix-data-service/model/derivation.scm		\
-  guix-data-service/model/guix-revision-package.scm	\
-  guix-data-service/model/guix-revision.scm		\
-  guix-data-service/model/package-metadata.scm		\
-  guix-data-service/model/package.scm			\
-  guix-data-service/model/utils.scm			\
-  guix-data-service/web/controller.scm			\
-  guix-data-service/web/render.scm			\
-  guix-data-service/web/server.scm			\
-  guix-data-service/web/sxml.scm			\
-  guix-data-service/web/util.scm			\
+SOURCES =							\
+  guix-data-service/builds.scm					\
+  guix-data-service/comparison.scm				\
+  guix-data-service/config.scm					\
+  guix-data-service/jobs.scm					\
+  guix-data-service/jobs/load-new-guix-revision.scm		\
+  guix-data-service/model/build-server.scm			\
+  guix-data-service/model/build-status.scm			\
+  guix-data-service/model/build.scm				\
+  guix-data-service/model/derivation.scm			\
+  guix-data-service/model/guix-revision-package-derivation.scm	\
+  guix-data-service/model/guix-revision.scm			\
+  guix-data-service/model/package-derivation.scm		\
+  guix-data-service/model/package-metadata.scm			\
+  guix-data-service/model/package.scm				\
+  guix-data-service/model/utils.scm				\
+  guix-data-service/web/controller.scm				\
+  guix-data-service/web/render.scm				\
+  guix-data-service/web/server.scm				\
+  guix-data-service/web/sxml.scm				\
+  guix-data-service/web/util.scm				\
   guix-data-service/web/view/html.scm
diff --git a/guix-data-service/comparison.scm b/guix-data-service/comparison.scm
index e3190ad..8688f84 100644
--- a/guix-data-service/comparison.scm
+++ b/guix-data-service/comparison.scm
@@ -12,20 +12,56 @@
             package-data-vhashes->new-packages
             package-data-vhashes->removed-packages
             package-data-version-changes
-            package-data-other-changes))
+            package-data-derivation-changes))
 
 (define (package-differences-data conn base_guix_revision_id target_guix_revision_id)
   (define query
-    "WITH base_packages AS (
-  SELECT packages.* FROM packages INNER JOIN guix_revision_packages ON packages.id = guix_revision_packages.package_id WHERE revision_id = $1
+    "
+WITH base_packages AS (
+  SELECT packages.*, derivations.file_name,
+    package_derivations.system, package_derivations.target
+  FROM packages
+  INNER JOIN package_derivations
+    ON packages.id = package_derivations.package_id
+  INNER JOIN derivations
+    ON package_derivations.derivation_id = derivations.id
+  WHERE package_derivations.id IN (
+    SELECT guix_revision_package_derivations.package_derivation_id
+    FROM guix_revision_package_derivations
+    WHERE revision_id = $1
+  )
 ), target_packages AS (
-  SELECT packages.* FROM packages INNER JOIN guix_revision_packages ON packages.id = guix_revision_packages.package_id WHERE revision_id = $2
+  SELECT packages.*, derivations.file_name,
+    package_derivations.system, package_derivations.target
+  FROM packages
+  INNER JOIN package_derivations
+    ON packages.id = package_derivations.package_id
+  INNER JOIN derivations
+    ON package_derivations.derivation_id = derivations.id
+  WHERE package_derivations.id IN (
+    SELECT guix_revision_package_derivations.package_derivation_id
+    FROM guix_revision_package_derivations
+    WHERE revision_id = $2
+  )
 )
-SELECT base_packages.name, base_packages.version, base_packages.package_metadata_id, base_packages.derivation_id, target_packages.name, target_packages.version, target_packages.package_metadata_id, target_packages.derivation_id
+SELECT base_packages.name, base_packages.version,
+  base_packages.package_metadata_id, base_packages.file_name,
+  base_packages.system, base_packages.target,
+  target_packages.name, target_packages.version,
+  target_packages.package_metadata_id, target_packages.file_name,
+  target_packages.system, target_packages.target
 FROM base_packages
-FULL OUTER JOIN target_packages ON base_packages.name = target_packages.name AND base_packages.version = target_packages.version
-WHERE (base_packages.id IS NULL OR target_packages.id IS NULL OR base_packages.id != target_packages.id)
-ORDER BY base_packages.name, base_packages.version, target_packages.name, target_packages.version")
+FULL OUTER JOIN target_packages
+  ON base_packages.name = target_packages.name
+  AND base_packages.version = target_packages.version
+  AND base_packages.system = target_packages.system
+  AND base_packages.target = target_packages.target
+WHERE
+  base_packages.id IS NULL OR
+  target_packages.id IS NULL OR
+  base_packages.id != target_packages.id OR
+  base_packages.file_name != target_packages.file_name
+ORDER BY base_packages.name DESC, base_packages.version, target_packages.name, target_packages.version")
 
   (exec-query conn query (list base_guix_revision_id target_guix_revision_id)))
 
@@ -40,7 +76,7 @@ ORDER BY base_packages.name, base_packages.version, target_packages.name, target
 
   (apply values
          (fold (lambda (row result)
-                 (let-values (((base-row-part target-row-part) (split-at row 4)))
+                 (let-values (((base-row-part target-row-part) (split-at row 6)))
                    (match result
                      ((base-package-data target-package-data)
                       (list (add-data-to-vhash base-row-part base-package-data)
@@ -63,24 +99,29 @@ ORDER BY base_packages.name, base_packages.version, target_packages.name, target
     derivation-data))
 
 (define (package-data-vhash->derivations-and-build-status conn packages-vhash)
-  (define (vhash->derivation-ids vhash)
+  (define (vhash->derivation-file-names vhash)
     (vhash-fold (lambda (key value result)
                   (cons (third value)
                         result))
                 '()
                 vhash))
 
-  (let* ((derivation-ids
-          (vhash->derivation-ids packages-vhash))
+  (let* ((derivation-file-names
+          (vhash->derivation-file-names packages-vhash))
          (derivation-data
-          (select-derivations-and-build-status-by-id conn derivation-ids)))
+          (select-derivations-and-build-status-by-file-name
+           conn
+           derivation-file-names)))
     derivation-data))
 
 (define (package-data-vhash->package-name-and-version-vhash vhash)
   (vhash-fold (lambda (name details result)
-                (vhash-cons (cons name (first details))
-                            (cdr details)
-                            result))
+                (let ((key (cons name (first details))))
+                  (vhash-cons key
+                              (cons (cdr details)
+                                    (or (and=> (vhash-assoc key result) cdr)
+                                        '()))
+                              (vhash-delete key result))))
               vlist-null
               vhash))
 
@@ -99,16 +140,29 @@ ORDER BY base_packages.name, base_packages.version, target_packages.name, target
                  base-packages-vhash)))
 
 (define (package-data-vhash->package-versions-vhash package-data-vhash)
+  (define (system-and-target<? a b)
+    (if (string=? (car a) (car b))
+        (string<? (cdr a) (cdr b))
+        (string<? (car a) (car b))))
+
+  (define (add-version-system-and-target-to-alist alist data)
+    (match data
+      ((version package-metadata-id derivation-id system target)
+       (let ((systems-for-version (or (and=> (assoc version alist) cdr)
+                                      '())))
+         `((,version . ,(sort (cons (cons system target)
+                                    systems-for-version)
+                              system-and-target<?))
+           ,@(alist-delete version alist))))))
+
   (vhash-fold (lambda (name details result)
                 (let ((version (first details))
-                      (known-versions (vhash-assoc name result)))
-                  (if known-versions
-                      (vhash-cons name
-                                  (cons version known-versions)
-                                  (vhash-delete name result))
-                      (vhash-cons name
-                                  (list version)
-                                  result))))
+                      (known-versions (or (and=> (vhash-assoc name result) cdr)
+                                          '())))
+                  (vhash-cons name
+                              (add-version-system-and-target-to-alist known-versions
+                                                                      details)
+                              (vhash-delete name result))))
               vlist-null
               package-data-vhash))
 
@@ -124,30 +178,42 @@ ORDER BY base_packages.name, base_packages.version, target_packages.name, target
                         (begin
                           (if (equal? base-versions target-versions)
                               result
-                              `((,name . ((base . ,base-versions)
-                                          (target . ,target-versions)))
+                              `((,name . ((base . ,(map car base-versions))
+                                          (target . ,(map car target-versions))))
                                 ,@result)))
                         result)))
                 '()
                 target-versions)))
 
-(define (package-data-other-changes base-packages-vhash target-packages-vhash)
+(define (package-data-derivation-changes base-packages-vhash target-packages-vhash)
   (define base-package-details-by-name-and-version
     (package-data-vhash->package-name-and-version-vhash base-packages-vhash))
 
   (define target-package-details-by-name-and-version
     (package-data-vhash->package-name-and-version-vhash target-packages-vhash))
 
-  (vhash-fold (lambda (name-and-version target-details result)
-                (let ((base-packages-entry
-                       (vhash-assoc name-and-version base-package-details-by-name-and-version)))
-                  (if base-packages-entry
-                      (let ((base-details (cdr base-packages-entry)))
-                        (if (equal? base-details target-details)
-                            result
-                            `((,name-and-version . ((base . ,base-details)
-                                                    (target . ,target-details)))
-                              ,@result)))
-                      result)))
-              '()
-              target-package-details-by-name-and-version))
+  (define (derivation-system-and-target-list->alist lst)
+    (if (null? lst)
+        '()
+        `((,(cdr (first lst)) . ,(car (first lst)))
+          ,@(derivation-system-and-target-list->alist (cdr lst)))))
+
+  (vhash-fold
+   (lambda (name-and-version target-packages-entry result)
+     (let ((base-packages-entry
+            (vhash-assoc name-and-version
+                         base-package-details-by-name-and-version)))
+       (if base-packages-entry
+           (let ((base-derivations (map cdr (cdr base-packages-entry)))
+                 (target-derivations (map cdr target-packages-entry)))
+             (if (equal? base-derivations target-derivations)
+                 result
+                 `((,name-and-version
+                    . ((base . ,(derivation-system-and-target-list->alist
+                                 base-derivations))
+                       (target . ,(derivation-system-and-target-list->alist
+                                   target-derivations))))
+                   ,@result)))
+           result)))
+   '()
+   target-package-details-by-name-and-version))
diff --git a/guix-data-service/jobs/load-new-guix-revision.scm b/guix-data-service/jobs/load-new-guix-revision.scm
index dcdd83e..23044ec 100644
--- a/guix-data-service/jobs/load-new-guix-revision.scm
+++ b/guix-data-service/jobs/load-new-guix-revision.scm
@@ -7,43 +7,104 @@
   #:use-module (guix channels)
   #:use-module (guix inferior)
   #:use-module (guix profiles)
+  #:use-module (guix progress)
   #:use-module (guix packages)
   #:use-module (guix derivations)
   #:use-module (guix build utils)
   #:use-module (guix-data-service model package)
   #:use-module (guix-data-service model guix-revision)
-  #:use-module (guix-data-service model guix-revision-package)
+  #:use-module (guix-data-service model package-derivation)
+  #:use-module (guix-data-service model guix-revision-package-derivation)
   #:use-module (guix-data-service model package-metadata)
   #:use-module (guix-data-service model derivation)
   #:export (process-next-load-new-guix-revision-job
             select-job-for-commit
             most-recent-n-load-new-guix-revision-jobs))
 
-(define (inferior-guix->package-ids store conn inf)
+(define (inferior-guix->package-derivation-ids store conn inf)
+  (define (inferior-package->systems-targets-and-derivations package)
+    (let ((supported-systems
+           (inferior-package-transitive-supported-systems package)))
+      (append-map
+       (lambda (system)
+         (filter-map
+          (lambda (target)
+            (catch
+              #t
+              (lambda ()
+                (list
+                 system
+                 target
+                 (inferior-package-derivation store package system
+                                              #:target
+                                              (if (string=? system target)
+                                                  #f
+                                                  target))))
+              (lambda args
+                (cond
+                 ((string-contains (simple-format #f "~A" (second args))
+                                   "&package-cross-build-system-error")
+                  #f)
+                 ((string-contains (simple-format #f "~A" (fourth args))
+                                   "(No cross-compilation for ")
+                  #f)
+                 (else
+                  (simple-format
+                   #t "guix-data-service: inferior-guix->package-ids: error processing derivation\n  ~A for system ~A and target ~A\n"
+                   package system target)
+                  (for-each (lambda (arg)
+                              (simple-format #t "arg: ~A\n" arg))
+                            args)
+                  #f)))))
+          supported-systems))
+       supported-systems)))
+
   (let* ((packages (inferior-packages inf))
          (packages-metadata-ids
           (inferior-packages->package-metadata-ids conn packages))
-         (packages-derivation-ids
+         (packages-count (length packages))
+         (progress-reporter (progress-reporter/bar
+                             packages-count
+                             (format #f "processing ~a packages"
+                                     packages-count)))
+         (systems-targets-and-derivations-by-package
+          (call-with-progress-reporter progress-reporter
+            (lambda (report)
+              (map
+               (lambda (package)
+                 (report)
+                 (inferior-package->systems-targets-and-derivations package))
+               packages))))
+         (package-ids
+          (inferior-packages->package-ids
+           conn packages packages-metadata-ids))
+         (derivation-ids
           (derivations->derivation-ids
            conn
-           (filter-map
-            (lambda (package)
-              (catch
-                #t
-                (lambda ()
-                  (inferior-package-derivation
-                   store package))
-                (lambda args
-                  (simple-format
-                   #t "guix-data-service: inferior-guix->package-ids: error processing derivation ~A\n"
-                   package)
-                  (simple-format
-                   #t "guix-data-service: inferior-guix->package-ids: error: ~A\n" args)
-                  #f)))
-            packages))))
+           (append-map
+            (lambda (system-targets-and-derivations)
+              (map third system-targets-and-derivations))
+            systems-targets-and-derivations-by-package)))
+         (flat-package-ids-systems-and-targets
+          (append-map
+           (lambda (package-id system-targets-and-derivations)
+             (map (match-lambda
+                    ((system target derivation)
+                     (list package-id
+                           system
+                           target)))
+                  system-targets-and-derivations))
+           package-ids
+           systems-targets-and-derivations-by-package)))
 
-    (inferior-packages->package-ids
-     conn packages packages-metadata-ids packages-derivation-ids)))
+    (insert-package-derivations conn
+                                flat-package-ids-systems-and-targets
+                                derivation-ids)))
+
+(define (inferior-package-transitive-supported-systems package)
+  ((@@ (guix inferior) inferior-package-field)
+   package
+   'package-transitive-supported-systems))
 
 (define (guix-store-path store)
   (let* ((guix-package (@ (gnu packages package-management)
@@ -140,17 +201,21 @@
     (inferior-eval '(use-modules (guix grafts)) inf)
     (inferior-eval '(%graft? #f) inf)
 
-    (let ((package-ids (inferior-guix->package-ids store conn inf)))
-      (exec-query conn "BEGIN")
+    (exec-query conn "BEGIN")
+    (let ((package-derivation-ids
+           (inferior-guix->package-derivation-ids store conn inf))
+          (guix-revision-id
+           (insert-guix-revision conn url commit store_path)))
 
-      (let ((guix-revision-id
-             (insert-guix-revision conn url commit store_path)))
-        (insert-guix-revision-packages conn guix-revision-id package-ids))
+      (insert-guix-revision-package-derivations conn
+                                                guix-revision-id
+                                                package-derivation-ids)
 
       (exec-query conn "COMMIT")
 
       (simple-format
-       #t "Successfully loaded ~A packages\n" (length package-ids)))
+       #t "Successfully loaded ~A package/derivation pairs\n"
+       (length package-derivation-ids)))
 
     (close-inferior inf)))
 
diff --git a/guix-data-service/model/derivation.scm b/guix-data-service/model/derivation.scm
index 305c260..b38efc7 100644
--- a/guix-data-service/model/derivation.scm
+++ b/guix-data-service/model/derivation.scm
@@ -5,16 +5,18 @@
   #:use-module (squee)
   #:use-module (guix base32)
   #:use-module (guix inferior)
+  #:use-module (guix memoization)
   #:use-module (guix derivations)
   #:use-module (guix-data-service model utils)
   #:export (select-derivation-by-file-name
             select-derivation-outputs-by-derivation-id
             select-derivation-by-output-filename
             select-derivations-using-output
+            select-derivations-by-revision-name-and-version
             select-derivation-inputs-by-derivation-id
             select-existing-derivations
             select-derivations-by-id
-            select-derivations-and-build-status-by-id
+            select-derivations-and-build-status-by-file-name
             insert-into-derivations
             derivations->derivation-ids))
 
@@ -62,6 +64,36 @@
 
   (exec-query conn query (list output-id)))
 
+(define (select-derivations-by-revision-name-and-version
+         conn revision-commit-hash name version)
+  (define query "
+SELECT derivations.system, package_derivations.target, derivations.file_name,
+  latest_build_status.status
+FROM derivations
+INNER JOIN package_derivations
+  ON derivations.id = package_derivations.derivation_id
+INNER JOIN packages
+  ON package_derivations.package_id = packages.id
+INNER JOIN guix_revision_package_derivations
+  ON package_derivations.id = guix_revision_package_derivations.package_derivation_id
+INNER JOIN guix_revisions
+  ON guix_revision_package_derivations.revision_id = guix_revisions.id
+LEFT OUTER JOIN builds ON derivations.id = builds.derivation_id
+LEFT OUTER JOIN (
+  SELECT DISTINCT ON (internal_build_id) *
+  FROM build_status
+  ORDER BY internal_build_id, status_fetched_at DESC
+) AS latest_build_status
+  ON builds.internal_id = latest_build_status.internal_build_id
+WHERE guix_revisions.commit = $1
+  AND packages.name = $2
+  AND packages.version = $3
+ORDER BY derivations.system DESC,
+         package_derivations.target DESC,
+         derivations.file_name")
+
+  (exec-query conn query (list revision-commit-hash name version)))
+
 (define (insert-derivation-outputs conn
                                    derivation-id
                                    names-and-derivation-outputs)
@@ -166,21 +198,22 @@
     ((result)
      result)))
 
-(define (select-derivation-output-id conn name path)
-  (match (exec-query
-          conn
-          (string-append
-           "SELECT derivation_outputs.id FROM derivation_outputs "
-           "INNER JOIN derivations ON "
-           "derivation_outputs.derivation_id = derivations.id "
-           "WHERE derivations.file_name = '" path "' "
-           "AND derivation_outputs.name = '" name "';"))
-    (((id))
-     id)
-    (()
-     (error (simple-format
-             #f "cannot find derivation-output with name ~A and path ~A"
-             name path)))))
+(define select-derivation-output-id
+  (mlambda (conn name path)
+    (match (exec-query
+            conn
+            (string-append
+             "SELECT derivation_outputs.id FROM derivation_outputs "
+             "INNER JOIN derivations ON "
+             "derivation_outputs.derivation_id = derivations.id "
+             "WHERE derivations.file_name = '" path "' "
+             "AND derivation_outputs.name = '" name "';"))
+      (((id))
+       id)
+      (()
+       (error (simple-format
+               #f "cannot find derivation-output with name ~A and path ~A"
+               name path))))))
 
 (define (select-derivation-outputs-by-derivation-id conn id)
   (define query
@@ -211,7 +244,7 @@
 
   (exec-query conn query (list id)))
 
-(define (insert-derivation-input conn derivation-id derivation-input)
+(define (insert-derivation-inputs conn derivation-id derivation-inputs)
   (define (insert-into-derivation-inputs output-ids)
     (string-append "INSERT INTO derivation_inputs "
                    "(derivation_id, derivation_output_id) VALUES "
@@ -224,16 +257,19 @@
                     ",")
                    ";"))
 
-  (match derivation-input
-    (($ <derivation-input> path sub-derivations)
-     (exec-query
-      conn
-      (insert-into-derivation-inputs
-       (map (lambda (sub-derivation)
-              (select-derivation-output-id conn
-                                           sub-derivation
-                                           path))
-            sub-derivations))))))
+  (unless (null? derivation-inputs)
+    (exec-query
+     conn
+     (insert-into-derivation-inputs
+      (append-map
+       (match-lambda
+         (($ <derivation-input> path sub-derivations)
+          (map (lambda (sub-derivation)
+                 (select-derivation-output-id conn
+                                              sub-derivation
+                                              path))
+               sub-derivations)))
+       derivation-inputs)))))
 
 (define (select-from-derivation-source-files store-paths)
   (string-append
@@ -304,7 +340,34 @@
     (exec-query conn
                 (insert-into-derivation-sources sources-ids))))
 
-(define (insert-missing-derivations conn derivations)
+(define (insert-missing-derivations conn
+                                    derivation-ids-hash-table
+                                    derivations)
+  (define (ensure-input-derivations-exist input-derivation-file-names)
+    (unless (null? input-derivation-file-names)
+      (simple-format
+       #t "debug: ensure-input-derivations-exist: processing ~A derivations\n"
+       (length input-derivation-file-names))
+      (force-output)
+      (let* ((existing-derivation-entries
+              (derivation-file-names->vhash conn
+                                            derivation-ids-hash-table
+                                            input-derivation-file-names))
+
+             (missing-derivations-filenames
+              (filter (lambda (derivation-file-name)
+                        (not (vhash-assoc derivation-file-name
+                                          existing-derivation-entries)))
+                      input-derivation-file-names)))
+
+        (unless (null? missing-derivations-filenames)
+          ;; Ensure all the input derivations exist
+          (insert-missing-derivations
+           conn
+           derivation-ids-hash-table
+           (map read-derivation-from-file
+                missing-derivations-filenames))))))
+
   (define (insert-into-derivations)
     (string-append
      "INSERT INTO derivations "
@@ -331,24 +394,60 @@
      " RETURNING id"
      ";"))
 
-  (map (lambda (derivation-id derivation)
-         (insert-derivation-outputs conn
-                                    derivation-id
-                                    (derivation-outputs derivation))
+  (simple-format
+   #t "debug: insert-missing-derivations: inserting ~A derivations\n"
+   (length derivations))
+  (let ((derivation-ids
+         (map car (exec-query conn (insert-into-derivations)))))
 
-         (insert-derivation-sources conn
-                                    derivation-id
-                                    (derivation-sources derivation))
+    (simple-format
+     #t "debug: insert-missing-derivations: updating hash table\n")
+    (for-each (lambda (derivation derivation-id)
+                (hash-set! derivation-ids-hash-table
+                           (derivation-file-name derivation)
+                           derivation-id))
+              derivations
+              derivation-ids)
 
-         (for-each (lambda (derivation-input)
-                     (insert-derivation-input conn
-                                              derivation-id
-                                              derivation-input))
-                   (derivation-inputs derivation))
+    (simple-format
+     #t "debug: insert-missing-derivations: inserting outputs\n")
+    (for-each (lambda (derivation-id derivation)
+                (insert-derivation-outputs conn
+                                           derivation-id
+                                           (derivation-outputs derivation)))
+              derivation-ids
+              derivations)
 
-         derivation-id)
-       (map car (exec-query conn (insert-into-derivations)))
-       derivations))
+    (simple-format
+     #t "debug: insert-missing-derivations: inserting sources\n")
+    (for-each (lambda (derivation-id derivation)
+                (insert-derivation-sources conn
+                                           derivation-id
+                                           (derivation-sources derivation)))
+              derivation-ids
+              derivations)
+
+    (simple-format
+     #t "debug: insert-missing-derivations: ensure-input-derivations-exist\n")
+    (force-output)
+
+    (ensure-input-derivations-exist (deduplicate-strings
+                                     (map derivation-input-path
+                                          (append-map
+                                           derivation-inputs
+                                           derivations))))
+
+    (simple-format
+     #t "debug: insert-missing-derivations: inserting inputs\n")
+    (for-each (lambda (derivation-id derivation)
+                (insert-derivation-inputs conn
+                                          derivation-id
+                                          (derivation-inputs derivation)))
+
+              derivation-ids
+              derivations)
+
+    derivation-ids))
 
 (define (select-derivations-by-id conn ids)
   (define query
@@ -363,10 +462,10 @@
 
   (exec-query conn query))
 
-(define (select-derivations-and-build-status-by-id conn ids)
+(define (select-derivations-and-build-status-by-file-name conn file-names)
   (define query
     (string-append
-     "SELECT derivations.id, derivations.file_name, latest_build_status.status "
+     "SELECT derivations.file_name, latest_build_status.status "
      "FROM derivations "
      "LEFT OUTER JOIN builds ON derivations.id = builds.derivation_id "
      "LEFT OUTER JOIN "
@@ -375,60 +474,124 @@
      "ORDER BY internal_build_id, status_fetched_at DESC"
      ") AS latest_build_status "
      "ON builds.internal_id = latest_build_status.internal_build_id "
-     "WHERE derivations.id IN "
-     "(" (string-join (map (lambda (id)
-                             (simple-format #f "'~A'" id))
-                           ids)
+     "WHERE derivations.file_name IN "
+     "(" (string-join (map (lambda (file-name)
+                             (simple-format #f "'~A'" file-name))
+                           file-names)
                       ",")
      ");"))
 
   (exec-query conn query))
 
+(define (deduplicate-strings strings)
+  (pair-fold
+   (lambda (pair result)
+     (if (null? (cdr pair))
+         (cons (first pair) result)
+         (if (string=? (first pair) (second pair))
+             result
+             (cons (first pair) result))))
+   '()
+   (sort strings
+         (lambda (a b)
+           (string<? a b)))))
+
+(define (deduplicate-derivations derivations)
+  (define sorted-derivations
+    (sort derivations
+          (lambda (a b)
+            (string<? (derivation-file-name a)
+                      (derivation-file-name b)))))
+
+  (pair-fold
+   (match-lambda*
+     (((x) result)
+      (cons x result))
+     (((x y rest ...) result)
+      (if (string=? (derivation-file-name x)
+                    (derivation-file-name y))
+          result
+          (cons x result))))
+   '()
+   sorted-derivations))
+
+(define (derivation-file-names->vhash conn derivation-ids-hash-table file-names)
+  (simple-format #t "debug: derivation-file-names->vhash: ~A file-names\n"
+                 (length file-names))
+  (match (fold (match-lambda*
+                 ((file-name (result . missing-file-names))
+                  (let ((cached-id (hash-ref derivation-ids-hash-table
+                                             file-name)))
+                    (if cached-id
+                        (cons (vhash-cons file-name cached-id result)
+                              missing-file-names)
+                        (cons result
+                              (cons file-name missing-file-names))))))
+               (cons vlist-null '())
+               file-names)
+    ((result)
+     (simple-format
+      #t "debug: derivation-file-names->vhash: lookup ~A file-names, all found\n"
+      (length file-names))
+     result)
+    ((result . missing-file-names)
+     (simple-format
+      #t "debug: derivation-file-names->vhash: lookup ~A file-names, ~A not cached\n"
+      (length file-names) (length missing-file-names))
+     (let ((result-for-missing-file-names
+            (exec-query->vhash
+             conn
+             (select-existing-derivations missing-file-names)
+             second ;; file_name
+             first))) ;; id
+       (simple-format
+        #t "debug: derivation-file-names->vhash: adding ~A entries to the cache\n"
+        (vlist-length result-for-missing-file-names))
+       (vhash-fold (lambda (key value _)
+                     (hash-set! derivation-ids-hash-table key value))
+                   '()
+                   result-for-missing-file-names)
+
+       (vhash-fold
+        (lambda (key value combined)
+          (vhash-cons key value combined))
+        result
+        result-for-missing-file-names)))))
+
 (define (derivations->derivation-ids conn derivations)
-  (define (ensure-input-derivations-exist)
-    (let* ((missing-derivation-file-names (map derivation-file-name
-                                               derivations))
-
-           (input-derivation-file-names (delete-duplicates
-                                         (map derivation-input-path
-                                              (append-map
-                                               derivation-inputs
-                                               derivations)))))
-
-      ;; Ensure all the input derivations exist
-      (derivations->derivation-ids
-       conn
-       (map read-derivation-from-file
-            input-derivation-file-names))))
-
   (if (null? derivations)
       '()
-      (begin
-        (ensure-input-derivations-exist)
+      (let* ((derivations-count (length derivations))
+             (derivation-ids-hash-table (make-hash-table derivations-count)))
+        (simple-format
+         #t "debug: derivations->derivation-ids: processing ~A derivations\n"
+         derivations-count)
         (let* ((derivation-file-names (map derivation-file-name
                                            derivations))
 
-               (existing-derivation-entries (exec-query->vhash
-                                             conn
-                                             (select-existing-derivations
-                                              derivation-file-names)
-                                             second ;; file_name
-                                             first)) ;; id
+               (existing-derivation-entries
+                (derivation-file-names->vhash conn
+                                              derivation-ids-hash-table
+                                              derivation-file-names))
 
                (missing-derivations
-                (filter (lambda (derivation)
-                          (not (vhash-assoc (derivation-file-name derivation)
-                                            existing-derivation-entries)))
-                        derivations))
+                (deduplicate-derivations
+                 (filter (lambda (derivation)
+                           (not (vhash-assoc (derivation-file-name derivation)
+                                             existing-derivation-entries)))
+                         derivations)))
 
                (new-derivation-entries
                 (if (null? missing-derivations)
                     '()
-                    (insert-missing-derivations conn missing-derivations)))
+                    (insert-missing-derivations conn
+                                                derivation-ids-hash-table
+                                                missing-derivations)))
 
                (new-entries-id-lookup-vhash
                 (two-lists->vhash (map derivation-file-name missing-derivations)
                                   new-derivation-entries)))
+
           (map (lambda (derivation-file-name)
                  (cdr
                   (or (vhash-assoc derivation-file-name
diff --git a/guix-data-service/model/guix-revision-package-derivation.scm b/guix-data-service/model/guix-revision-package-derivation.scm
new file mode 100644
index 0000000..733dad2
--- /dev/null
+++ b/guix-data-service/model/guix-revision-package-derivation.scm
@@ -0,0 +1,20 @@
+(define-module (guix-data-service model guix-revision-package-derivation)
+  #:use-module (squee)
+  #:export (insert-guix-revision-package-derivations))
+
+(define (insert-guix-revision-package-derivations
+         conn guix-revision-id package-derivation-ids)
+  (define insert
+    (string-append "INSERT INTO guix_revision_package_derivations "
+                   "(revision_id, package_derivation_id) "
+                   "VALUES "
+                   (string-join (map (lambda (package-derivation-id)
+                                       (simple-format
+                                        #f "(~A, ~A)"
+                                        guix-revision-id
+                                        package-derivation-id))
+                                     package-derivation-ids)
+                                ", ")
+                   ";"))
+
+  (exec-query conn insert))
diff --git a/guix-data-service/model/guix-revision-package.scm b/guix-data-service/model/guix-revision-package.scm
deleted file mode 100644
index 2f710a4..0000000
--- a/guix-data-service/model/guix-revision-package.scm
+++ /dev/null
@@ -1,19 +0,0 @@
-(define-module (guix-data-service model guix-revision-package)
-  #:use-module (squee)
-  #:export (insert-guix-revision-packages))
-
-(define (insert-guix-revision-packages conn guix-revision-id package-ids)
-  (define insert
-    (string-append "INSERT INTO guix_revision_packages "
-                   "(revision_id, package_id) "
-                   "VALUES "
-                   (string-join (map (lambda (package-id)
-                                       (simple-format
-                                        #f "(~A, ~A)"
-                                        guix-revision-id
-                                        package-id))
-                                     package-ids)
-                                ", ")
-                   ";"))
-
-  (exec-query conn insert))
diff --git a/guix-data-service/model/package-derivation.scm b/guix-data-service/model/package-derivation.scm
new file mode 100644
index 0000000..6e87765
--- /dev/null
+++ b/guix-data-service/model/package-derivation.scm
@@ -0,0 +1,112 @@
+(define-module (guix-data-service model package-derivation)
+  #:use-module (srfi srfi-1)
+  #:use-module (ice-9 vlist)
+  #:use-module (ice-9 match)
+  #:use-module (squee)
+  #:use-module (guix-data-service model utils)
+  #:export (insert-package-derivations
+            count-packages-derivations-in-revision))
+
+(define (insert-missing-package-derivations conn entries)
+  (define query
+    (string-append
+     "INSERT INTO package_derivations "
+     "(package_id, derivation_id, system, target) VALUES "
+     (string-join
+      (map
+       (lambda (entry)
+         (apply simple-format
+                #f "(~A, ~A, '~A', '~A')"
+                entry))
+       entries)
+      ", ")
+     " RETURNING id"))
+
+  (exec-query conn query))
+
+(define (insert-package-derivations conn
+                                    package-ids-systems-and-targets
+                                    derivation-ids)
+  (define select-existing-package-derivation-entries
+    (string-append
+     "SELECT id, package_derivations.package_id,"
+     " package_derivations.derivation_id, package_derivations.system,"
+     " package_derivations.target "
+     "FROM package_derivations "
+     "JOIN (VALUES "
+     (string-join (map (match-lambda*
+                         (((package-id system target) derivation-id)
+                          (simple-format
+                           #f "(~A, ~A, '~A', '~A')"
+                           package-id
+                           derivation-id
+                           system
+                           target)))
+                       package-ids-systems-and-targets
+                       derivation-ids)
+                  ", ")
+     ") AS vals (package_id, derivation_id, system, target) "
+     "ON package_derivations.package_id = vals.package_id "
+     "AND package_derivations.derivation_id = vals.derivation_id "
+     "AND package_derivations.system = vals.system "
+     "AND package_derivations.target = vals.target"))
+
+  (define data-4-tuples
+    (map (match-lambda*
+           (((package-id system target) derivation-id)
+            (list package-id
+                  derivation-id
+                  system
+                  target)))
+         package-ids-systems-and-targets
+         derivation-ids))
+
+  (if (null? data-4-tuples)
+      '()
+      (begin
+        (let* ((existing-entries
+                (exec-query->vhash
+                 conn
+                 select-existing-package-derivation-entries
+                 cdr
+                 first)) ;; id
+
+               (missing-entries
+                (filter (lambda (4-tuple)
+                          (not (vhash-assoc 4-tuple existing-entries)))
+                        data-4-tuples))
+
+               (new-entry-ids
+                (if (null? missing-entries)
+                    '()
+                    (begin
+                      (vlist->list existing-entries)
+                      (insert-missing-package-derivations conn missing-entries))))
+
+               (new-entries-id-lookup-vhash
+                (two-lists->vhash missing-entries
+                                  new-entry-ids)))
+          (map (lambda (4-tuple)
+                 (cdr
+                  (or (vhash-assoc 4-tuple existing-entries)
+                      (vhash-assoc 4-tuple new-entries-id-lookup-vhash)
+                      (error "Missing entry"))))
+               data-4-tuples)))))
+
+(define (count-packages-derivations-in-revision conn commit-hash)
+  (define query
+    "
+SELECT package_derivations.system, package_derivations.target,
+COUNT(DISTINCT package_derivations.derivation_id)
+FROM package_derivations
+WHERE package_derivations.id IN (
+ SELECT guix_revision_package_derivations.package_derivation_id
+ FROM guix_revision_package_derivations
+ INNER JOIN guix_revisions
+   ON guix_revision_package_derivations.revision_id = guix_revisions.id
+ WHERE guix_revisions.commit = $1
+)
+GROUP BY package_derivations.system, package_derivations.target
+ORDER BY package_derivations.system DESC, package_derivations.target DESC")
+
+  (exec-query conn query (list commit-hash)))
diff --git a/guix-data-service/model/package-metadata.scm b/guix-data-service/model/package-metadata.scm
index 429538b..bd6cbe6 100644
--- a/guix-data-service/model/package-metadata.scm
+++ b/guix-data-service/model/package-metadata.scm
@@ -9,6 +9,7 @@
   #:use-module (guix inferior)
   #:use-module (guix-data-service model utils)
   #:export (select-package-metadata
+            select-package-metadata-by-revision-name-and-version
             insert-package-metadata
             inferior-packages->package-metadata-ids))
 
@@ -22,6 +23,29 @@
                               ",")
                  ");"))
 
+(define (select-package-metadata-by-revision-name-and-version
+         conn revision-commit-hash name version)
+  (define query "
+SELECT package_metadata.synopsis, package_metadata.description,
+  package_metadata.home_page
+FROM package_metadata
+INNER JOIN packages
+  ON package_metadata.id = packages.package_metadata_id
+WHERE packages.id IN (
+  SELECT package_derivations.package_id
+  FROM package_derivations
+  INNER JOIN guix_revision_package_derivations
+    ON package_derivations.id =
+    guix_revision_package_derivations.package_derivation_id
+  INNER JOIN guix_revisions
+    ON guix_revision_package_derivations.revision_id = guix_revisions.id
+  WHERE guix_revisions.commit = $1
+)
+  AND packages.name = $2
+  AND packages.version = $3")
+
+  (exec-query conn query (list revision-commit-hash name version)))
+
 (define (insert-package-metadata metadata-rows)
   (string-append "INSERT INTO package_metadata "
                  "(sha1_hash, synopsis, description, home_page) "
diff --git a/guix-data-service/model/package.scm b/guix-data-service/model/package.scm
index b5a38fa..bb01986 100644
--- a/guix-data-service/model/package.scm
+++ b/guix-data-service/model/package.scm
@@ -7,75 +7,93 @@
   #:use-module (guix-data-service model utils)
   #:export (select-existing-package-entries
             select-packages-in-revision
+            count-packages-in-revision
             insert-into-package-entries
             inferior-packages->package-ids))
 
 (define (select-existing-package-entries package-entries)
   (string-append "SELECT id, packages.name, packages.version, "
-                 "packages.package_metadata_id, packages.derivation_id "
+                 "packages.package_metadata_id "
                  "FROM packages "
                  "JOIN (VALUES "
                  (string-join (map (lambda (package-entry)
                                      (apply
                                       simple-format
-                                      #f "('~A', '~A', ~A, ~A)"
+                                      #f "('~A', '~A', ~A)"
                                       package-entry))
                                    package-entries)
                               ", ")
-                 ") AS vals (name, version, package_metadata_id, derivation_id) "
+                 ") AS vals (name, version, package_metadata_id) "
                  "ON packages.name = vals.name AND "
                  "packages.version = vals.version AND "
-                 "packages.package_metadata_id = vals.package_metadata_id AND "
-                 "packages.derivation_id = vals.derivation_id"
-                 ";"))
+                 "packages.package_metadata_id = vals.package_metadata_id"))
 
 (define (select-packages-in-revision conn commit-hash)
   (define query
-    (string-append
-     "SELECT packages.name, packages.version, packages.derivation_id "
-     "FROM packages "
-     "INNER JOIN guix_revision_packages"
-     " ON packages.id = guix_revision_packages.package_id "
-     "INNER JOIN guix_revisions"
-     " ON guix_revision_packages.revision_id = guix_revisions.id "
-     "WHERE guix_revisions.commit = $1 "
-     "ORDER BY packages.name, packages.version"))
+    "
+SELECT packages.name, packages.version, package_metadata.synopsis
+FROM packages
+INNER JOIN package_metadata
+  ON packages.package_metadata_id = package_metadata.id
+WHERE packages.id IN (
+ SELECT package_derivations.package_id
+ FROM package_derivations
+ INNER JOIN guix_revision_package_derivations
+   ON package_derivations.id = guix_revision_package_derivations.package_derivation_id
+ INNER JOIN guix_revisions
+   ON guix_revision_package_derivations.revision_id = guix_revisions.id
+ WHERE guix_revisions.commit = $1
+)
+ORDER BY packages.name, packages.version")
+
+  (exec-query conn query (list commit-hash)))
+
+(define (count-packages-in-revision conn commit-hash)
+  (define query
+    "
+SELECT COUNT(DISTINCT packages.name)
+FROM packages
+WHERE packages.id IN (
+ SELECT package_derivations.package_id
+ FROM package_derivations
+ INNER JOIN guix_revision_package_derivations
+   ON package_derivations.id = guix_revision_package_derivations.package_derivation_id
+ INNER JOIN guix_revisions
+   ON guix_revision_package_derivations.revision_id = guix_revisions.id
+ WHERE guix_revisions.commit = $1
+)")
 
   (exec-query conn query (list commit-hash)))
 
 (define (insert-into-package-entries package-entries)
   (string-append "INSERT INTO packages "
-                 "(name, version, package_metadata_id, derivation_id) VALUES "
+                 "(name, version, package_metadata_id) VALUES "
                  (string-join
                   (map
                    (match-lambda
-                     ((name version package_metadata_id derivation_id)
-                      (simple-format #f "('~A', '~A', ~A, ~A)"
+                     ((name version package_metadata_id)
+                      (simple-format #f "('~A', '~A', ~A)"
                                      name
                                      version
-                                     package_metadata_id
-                                     derivation_id)))
+                                     package_metadata_id)))
                    package-entries)
                   ",")
                  " RETURNING id"
                  ";"))
 
-(define (inferior-packages->package-ids conn packages metadata-ids derivation-ids)
+(define (inferior-packages->package-ids conn packages metadata-ids)
   (define package-entries
-    (map (lambda (package metadata-id derivation-id)
+    (map (lambda (package metadata-id)
            (list (inferior-package-name package)
                  (inferior-package-version package)
-                 metadata-id
-                 derivation-id))
+                 metadata-id))
          packages
-         metadata-ids
-         derivation-ids))
+         metadata-ids))
 
   (let* ((existing-package-entry-ids
           (exec-query->vhash conn
                              (select-existing-package-entries package-entries)
-                             ;; name, version, package_metadata_id and
-                             ;; derivation_id
+                             ;; name, version and package_metadata_id
                              cdr
                              first)) ;;id
          (missing-package-entries
diff --git a/guix-data-service/web/controller.scm b/guix-data-service/web/controller.scm
index 9f436dc..a8dd897 100644
--- a/guix-data-service/web/controller.scm
+++ b/guix-data-service/web/controller.scm
@@ -29,6 +29,8 @@
   #:use-module (guix-data-service comparison)
   #:use-module (guix-data-service model guix-revision)
   #:use-module (guix-data-service model package)
+  #:use-module (guix-data-service model package-derivation)
+  #:use-module (guix-data-service model package-metadata)
   #:use-module (guix-data-service model derivation)
   #:use-module (guix-data-service model build)
   #:use-module (guix-data-service jobs load-new-guix-revision)
@@ -113,16 +115,16 @@
            (version-changes
             (package-data-version-changes base-packages-vhash
                                           target-packages-vhash))
-           (other-changes
-            (package-data-other-changes base-packages-vhash
-                                        target-packages-vhash)))
+           (derivation-changes
+            (package-data-derivation-changes base-packages-vhash
+                                             target-packages-vhash)))
       (cond
        ((eq? content-type 'json)
         (render-json
          `((new-packages . ,new-packages)
            (removed-packages . ,removed-packages)
            (version-changes . ,version-changes)
-           (other-changes . ,other-changes))))
+           (derivation-changes . ,derivation-changes))))
        (else
         (apply render-html
                (compare base-commit
@@ -130,7 +132,7 @@
                         new-packages
                         removed-packages
                         version-changes
-                        other-changes)))))))
+                        derivation-changes)))))))
 
 (define (render-compare/derivations content-type
                                     conn
@@ -138,6 +140,15 @@
                                     base-revision-id
                                     target-commit
                                     target-revision-id)
+  (define (derivations->alist derivations)
+    (map (match-lambda
+           ((file-name buildstatus)
+            `((file_name . ,file-name)
+              (build_status . ,(if (string=? "")
+                                   "unknown"
+                                   buildstatus)))))
+         derivations))
+
   (let-values
       (((base-packages-vhash target-packages-vhash)
         (package-data->package-data-vhashes
@@ -156,9 +167,13 @@
        ((eq? content-type 'json)
         (render-json
          `((base . ((commit . ,base-commit)
-                    (derivations . ,base-derivations)))
+                    (derivations . ,(list->vector
+                                     (derivations->alist
+                                      base-derivations)))))
            (target . ((commit . ,target-commit)
-                      (derivations . ,target-derivations))))))
+                      (derivations . ,(list->vector
+                                       (derivations->alist
+                                        target-derivations))))))))
        (else
         (apply render-html
                (compare/derivations
@@ -174,11 +189,13 @@
                                  target-commit
                                  target-revision-id)
   (define (package-data-vhash->json vh)
-    (vhash-fold (lambda (name data result)
-                  (cons (string-append name "@" (car data))
-                        result))
-                '()
-                vh))
+    (delete-duplicates
+     (vhash-fold (lambda (name data result)
+                   (cons `((name . ,name)
+                           (version . ,(car data)))
+                         result))
+                 '()
+                 vh)))
 
   (let-values
       (((base-packages-vhash target-packages-vhash)
@@ -189,10 +206,14 @@
     (cond
      ((eq? content-type 'json)
       (render-json
-       `((base . ((commit . ,base-commit)
-                  (packages . ,(package-data-vhash->json base-packages-vhash))))
-         (target . ((commit . ,target-commit)
-                    (packages . ,(package-data-vhash->json target-packages-vhash)))))))
+       `((base
+          . ((commit . ,base-commit)
+             (packages . ,(list->vector
+                           (package-data-vhash->json base-packages-vhash)))))
+         (target
+          . ((commit . ,target-commit)
+             (packages . ,(list->vector
+                           (package-data-vhash->json target-packages-vhash))))))))
      (else
       (apply render-html
              (compare/packages
@@ -227,14 +248,16 @@
     (match derivation
       (()
        #f)
-      ((derivation)
+      (derivations
        (apply render-html
               (view-store-item filename
-                               derivation
-                               (match derivation
-                                 ((file-name output-id rest ...)
-                                  (select-derivations-using-output
-                                   conn output-id)))))))))
+                               derivations
+                               (map (lambda (derivation)
+                                      (match derivation
+                                        ((file-name output-id rest ...)
+                                         (select-derivations-using-output
+                                          conn output-id))))
+                                    derivations)))))))
 
 (define (controller request body conn)
   (match-lambda
@@ -249,13 +272,31 @@
     ((GET "revision" commit-hash)
      (apply render-html
             (view-revision commit-hash
-                           (select-packages-in-revision conn
-                                                        commit-hash))))
+                           (count-packages-in-revision conn
+                                                       commit-hash)
+                           (count-packages-derivations-in-revision conn
+                                                                   commit-hash))))
+    ((GET "revision" commit-hash "packages")
+     (apply render-html
+            (view-revision-packages commit-hash
+                                    (select-packages-in-revision
+                                     conn commit-hash))))
     ((GET "revision" commit-hash "package" name version)
      (apply render-html
-            (view-revision-package-and-version commit-hash
-                                               name
-                                               version)))
+            (view-revision-package-and-version
+             commit-hash
+             name
+             version
+             (select-package-metadata-by-revision-name-and-version
+              conn
+              commit-hash
+              name
+              version)
+             (select-derivations-by-revision-name-and-version
+              conn
+              commit-hash
+              name
+              version))))
     ((GET "gnu" "store" filename)
      (if (string-suffix? ".drv" filename)
          (render-derivation conn (string-append "/gnu/store/" filename))
diff --git a/guix-data-service/web/view/html.scm b/guix-data-service/web/view/html.scm
index c7c353a..dcd2f15 100644
--- a/guix-data-service/web/view/html.scm
+++ b/guix-data-service/web/view/html.scm
@@ -23,9 +23,12 @@
   #:use-module (ice-9 match)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-19)
+  #:use-module (texinfo)
+  #:use-module (texinfo html)
   #:export (index
             view-revision-package-and-version
             view-revision
+            view-revision-packages
             view-builds
             view-derivation
             view-store-item
@@ -171,7 +174,9 @@
                        (td ,source))))
                   queued-guix-revisions)))))))))
 
-(define (view-revision-package-and-version revision-commit-hash name version)
+(define (view-revision-package-and-version revision-commit-hash name version
+                                           package-metadata
+                                           derivations)
   (layout
    #:extra-headers
    '((cache-control . ((max-age . 60))))
@@ -181,9 +186,48 @@
       (@ (class "container"))
       (div
        (@ (class "row"))
-       (h1 "Package " ,name " @ " ,version))))))
+       (h3 (a (@ (href ,(string-append
+                         "/revision/" revision-commit-hash)))
+              "Revision " (samp ,revision-commit-hash))))
+      (div
+       (@ (class "row"))
+       (h1 "Package " ,name " @ " ,version))
+      (div
+       (@ (class "row"))
+       ,(match package-metadata
+          (((synopsis description home-page))
+           `(dl
+             (@ (class "dl-horizontal"))
+             (dt "Synopsis")
+             (dd ,(stexi->shtml (texi-fragment->stexi synopsis)))
+             (dt "Description")
+             (dd ,(stexi->shtml (texi-fragment->stexi description)))
+             (dt "Home page")
+             (dd (a (@ (href ,home-page))
+                    ,home-page))))))
+      (div
+       (@ (class "row"))
+       (table
+        (@ (class "table"))
+        (thead
+         (tr
+          (th "System")
+          (th "Target")
+          (th "Derivation")
+          (th "Build status")))
+        (tbody
+         ,@(map
+            (match-lambda
+              ((system target file-name status)
+               `(tr
+                 (td (samp ,system))
+                 (td (samp ,target))
+                 (td (a (@ (href ,file-name))
+                        ,(display-store-item-short file-name)))
+                 (td ,(build-status-span status)))))
+            derivations))))))))
 
-(define (view-revision commit-hash packages)
+(define (view-revision commit-hash packages-count derivations-count)
   (layout
    #:extra-headers
    '((cache-control . ((max-age . 60))))
@@ -196,23 +240,78 @@
        (h1 "Revision " (samp ,commit-hash)))
       (div
        (@ (class "row"))
-       (h3 "Packages")
+       (div
+        (@ (class "col-md-6"))
+        (h3 "Packages")
+        (strong (@ (class "text-center")
+                   (style "font-size: 2em; display: block;"))
+                ,packages-count)
+        (a (@ (class "btn btn-default btn-lg")
+              (href ,(string-append "/revision/" commit-hash
+                                    "/packages")))
+           "View packages"))
+       (div
+        (@ (class "col-md-6"))
+        (h3 "Derivations")
+        (table
+         (@ (class "table"))
+         (thead
+          (tr
+           (th "System")
+           (th "Target")
+           (th "Distinct derivations")))
+         (tbody
+          ,@(map (match-lambda
+                   ((system target count)
+                    (if (string=? system target)
+                        `(tr
+                          (td (@ (class "text-center")
+                                 (colspan 2))
+                              (samp ,system))
+                          (td (samp ,count)))
+                        `(tr
+                          (td (samp ,system))
+                          (td (samp ,target))
+                          (td (samp ,count))))))
+                 derivations-count)))))))))
+
+(define (view-revision-packages revision-commit-hash packages)
+  (layout
+   #:extra-headers
+   '((cache-control . ((max-age . 60))))
+   #:body
+   `(,(header)
+     (div
+      (@ (class "container"))
+      (div
+       (@ (class "row"))
+       (h3 (a (@ (href ,(string-append
+                         "/revision/" revision-commit-hash)))
+              "Revision " (samp ,revision-commit-hash))))
+      (div
+       (@ (class "row"))
+       (h1 "Packages")
        (table
-        (@ (class "table"))
+        (@ (class "table table-responsive"))
         (thead
          (tr
           (th (@ (class "col-md-3")) "Name")
-          (th (@ (class "col-md-3")) "Version")))
+          (th (@ (class "col-md-3")) "Version")
+          (th (@ (class "col-md-3")) "Synopsis")
+          (th (@ (class "col-md-3")) "")))
         (tbody
          ,@(map
             (match-lambda
-              ((name version rest ...)
+              ((name version synopsis)
                `(tr
-                 (td (a (@ (href ,(string-append
-                                   "/revision/" commit-hash
+                 (td ,name)
+                 (td ,version)
+                 (td ,(stexi->shtml (texi-fragment->stexi synopsis)))
+                 (td (@ (class "text-right"))
+                     (a (@ (href ,(string-append
+                                   "/revision/" revision-commit-hash
                                    "/package/" name "/" version)))
-                        ,name))
-                 (td ,version))))
+                        "More information")))))
             packages))))))))
 
 (define (view-builds stats builds)
@@ -237,7 +336,7 @@
             (match-lambda
               ((status count)
                `(tr
-                 (td ,status)
+                 (td ,(build-status-span status))
                  (td ,count))))
             stats))))
       (div
@@ -257,13 +356,8 @@
               ((build-id build-server-url derivation-file-name
                          status-fetched-at starttime stoptime status)
                `(tr
-                 (td (@ (class ,(cond
-                                 ((string=? status "succeeded")
-                                  "bg-success")
-                                 ((string=? status "failed")
-                                  "bg-danger")
-                                 (else ""))))
-                     ,status)
+                 (td (@ (class "text-center"))
+                     ,(build-status-span status))
                  (td (a (@ (href ,derivation-file-name))
                         ,(display-store-item-short derivation-file-name)))
                  (td ,starttime)
@@ -273,6 +367,31 @@
                         "View build on " ,build-server-url)))))
             builds))))))))
 
+(define (build-status-span status)
+  `(span (@ (class ,(string-append
+                     "label label-"
+                     (assoc-ref
+                      '(("scheduled" . "info")
+                        ("started" . "primary")
+                        ("succeeded" . "success")
+                        ("failed" . "danger")
+                        ("failed-dependency" . "warning")
+                        ("failed-other" . "danger")
+                        ("canceled" . "default")
+                        ("" . "default"))
+                      status)))
+            (style "display: inline-block; font-size: 1.2em; margin-top: 0.4em;"))
+         ,(assoc-ref
+           '(("scheduled" . "Scheduled")
+             ("started" . "Started")
+             ("succeeded" . "Succeeded")
+             ("failed" . "Failed")
+             ("failed-dependency" . "Failed (dependency)")
+             ("failed-other" . "Failed (other)")
+             ("canceled" . "Canceled")
+             ("" . "Unknown"))
+           status)))
+
 (define (display-store-item-short item)
   `((span (@ (style "font-size: small; font-family: monospace; display: block;"))
           ,(string-take item 44))
@@ -280,9 +399,9 @@
           ,(string-drop item 44))))
 
 (define (display-store-item item)
-  `((span (@ (style "font-size: small; font-family: monospace;"))
+  `((span (@ (style "font-size: small; font-family: monospace; white-space: nowrap;"))
           ,(string-take item 44))
-    (span (@ (style "font-size: x-large; font-family: monospace;"))
+    (span (@ (style "font-size: x-large; font-family: monospace; white-space: nowrap;"))
           ,(string-drop item 44))))
 
 (define (display-store-item-title item)
@@ -300,7 +419,7 @@
        ,(string-append
          "/" (string-join fileparts "/"))))))
 
-(define (view-store-item filename derivation derivations-using-store-item)
+(define (view-store-item filename derivations derivations-using-store-item-list)
   (layout
    #:extra-headers
    '((cache-control . ((max-age . 60))))
@@ -311,28 +430,31 @@
       (div
        (@ (class "row"))
        ,(display-store-item-title filename))
-      (div
-       (@ (class "row"))
-       (h4 "Derivation: ")
-       ,(match derivation
-          ((file-name output-id)
-           `(a (@ (href ,file-name))
-               ,(display-store-item file-name)))))
-      (div
-       (@ (class "row"))
-       (h2 "Derivations using this store item "
-           ,(let ((count (length derivations-using-store-item)))
-              (if (eq? count 100)
-                  "(> 100)"
-                  (simple-format #f "(~A)" count))))
-       (ul
-        (@ (class "list-unstyled"))
-        ,(map
-          (match-lambda
-            ((file-name)
-             `(li (a (@ (href ,file-name))
-                     ,(display-store-item file-name)))))
-          derivations-using-store-item)))))))
+      ,@(map (lambda (derivation derivations-using-store-item)
+               `((div
+                  (@ (class "row"))
+                  (h4 "Derivation: ")
+                  ,(match derivation
+                     ((file-name output-id)
+                      `(a (@ (href ,file-name))
+                          ,(display-store-item file-name)))))
+                 (div
+                  (@ (class "row"))
+                  (h2 "Derivations using this store item "
+                      ,(let ((count (length derivations-using-store-item)))
+                         (if (eq? count 100)
+                             "(> 100)"
+                             (simple-format #f "(~A)" count))))
+                  (ul
+                   (@ (class "list-unstyled"))
+                   ,(map
+                     (match-lambda
+                       ((file-name)
+                        `(li (a (@ (href ,file-name))
+                                ,(display-store-item file-name)))))
+                     derivations-using-store-item)))))
+             derivations
+             derivations-using-store-item-list)))))
 
 (define (view-derivation derivation derivation-inputs derivation-outputs
                          builds)
@@ -381,17 +503,22 @@
                 (td "System")
                 (td (samp ,system)))))))
         (h3 "Build status")
-        ,@(map
-           (match-lambda
-             ((build-id build-server-url status-fetched-at
-                        starttime stoptime status)
-              `(div
-                (@ (class "text-center"))
-                (div ,status)
-                (a (@ (href ,(simple-format
-                              #f "~Abuild/~A" build-server-url build-id)))
-                   "View build on " ,build-server-url))))
-           builds))
+        ,@(if (null? builds)
+              `((div
+                 (@ (class "text-center"))
+                 ,(build-status-span "")))
+              (map
+               (match-lambda
+                 ((build-id build-server-url status-fetched-at
+                            starttime stoptime status)
+                  `(div
+                    (@ (class "text-center"))
+                    (div ,(build-status-span status))
+                    (a (@ (style "display: inline-block; margin-top: 0.4em;")
+                          (href ,(simple-format
+                                  #f "~Abuild/~A" build-server-url build-id)))
+                       "View build on " ,build-server-url))))
+               builds)))
        (div
         (@ (class "col-md-4"))
         (h3 "Outputs")
@@ -413,7 +540,7 @@
                  new-packages
                  removed-packages
                  version-changes
-                 other-changes)
+                 derivation-changes)
   (define query-params
     (string-append "?base_commit=" base-commit
                    "&target_commit=" target-commit))
@@ -516,24 +643,61 @@
                   version-changes)))))
       (div
        (@ (class "row"))
-       (h3 "Other changed packages")
-       ,@(if (null? other-changes)
-             '((p "No other changes"))
-             `((p "The metadata or derivation for these packages has changed.")
-               (table
-                (@ (class "table"))
-                (thead
-                 (tr
-                  (th (@ (class "col-md-3")) "Name")
-                  (th (@ (class "col-md-9")) "Version")))
-                (tbody
-                 ,@(map
-                    (match-lambda
-                      (((name . version) . (metadata-id derivation-id))
-                       `(tr
-                         (td ,name)
-                         (td ,version))))
-                    other-changes))))))))))
+       (h3 "Package derivation changes")
+       ,(if
+         (null? derivation-changes)
+         '(p "No derivation changes")
+         `(table
+           (@ (class "table")
+              (style "table-layout: fixed;"))
+           (thead
+            (tr
+             (th "Name")
+             (th "Version")
+             (th "System")
+             (th "Target")
+             (th (@ (class "col-xs-5")) "Derivations")))
+           (tbody
+            ,@(append-map
+               (match-lambda
+                 (((name . version) . (('base . base-derivations)
+                                       ('target . target-derivations)))
+                  (let* ((system-and-versions
+                          (delete-duplicates
+                           (append (map car base-derivations)
+                                   (map car target-derivations))))
+                         (data-columns
+                          (map
+                           (lambda (system-and-target)
+                             (let ((base-derivation-file-name
+                                    (assoc-ref base-derivations system-and-target))
+                                   (target-derivation-file-name
+                                    (assoc-ref target-derivations system-and-target)))
+                               `((td (samp (@ (style "white-space: nowrap;"))
+                                           ,(car system-and-target)))
+                                 (td (samp (@ (style "white-space: nowrap;"))
+                                           ,(cdr system-and-target)))
+                                 (td (a (@ (style "display: block;")
+                                           (href ,base-derivation-file-name))
+                                        (span (@ (class "text-danger glyphicon glyphicon-minus pull-left")
+                                                 (style "font-size: 1.5em; padding-right: 0.4em;")))
+                                        ,(display-store-item-short base-derivation-file-name))
+                                     (a (@ (style "display: block;")
+                                           (href ,target-derivation-file-name))
+                                        (span (@ (class "text-success glyphicon glyphicon-plus pull-left")
+                                                 (style "font-size: 1.5em; padding-right: 0.4em;")))
+                                        ,(display-store-item-short target-derivation-file-name))))))
+                           system-and-versions)))
+
+                    `((tr (td (@ (rowspan , (length system-and-versions)))
+                              ,name)
+                          (td (@ (rowspan , (length system-and-versions)))
+                              ,version)
+                          ,@(car data-columns))
+                      ,@(map (lambda (data-row)
+                               `(tr ,data-row))
+                             (cdr data-columns))))))
+               derivation-changes)))))))))
 
 (define (compare/derivations base-commit
                              target-commit
@@ -575,11 +739,11 @@
         (tbody
          ,@(map
             (match-lambda
-              ((id file-name build-status)
+              ((file-name build-status)
                `(tr
                  (td (a (@ (href ,file-name))
                         ,(display-store-item file-name)))
-                 (td ,build-status))))
+                 (td ,(build-status-span build-status)))))
             base-derivations))))
       (div
        (@ (class "row"))
@@ -596,11 +760,11 @@
         (tbody
          ,@(map
             (match-lambda
-              ((id file-name build-status)
+              ((file-name build-status)
                `(tr
                  (td (a (@ (href ,file-name))
                         ,(display-store-item file-name)))
-                 (td ,build-status))))
+                 (td ,(build-status-span build-status)))))
             target-derivations))))))))
 
 (define (compare/packages base-commit
@@ -638,16 +802,25 @@
         (@ (class "table"))
         (thead
          (tr
-          (th (@ (class "col-md-6")) "Name")
-          (th (@ (class "col-md-6")) "Version")))
+          (th (@ (class "col-md-4")) "Name")
+          (th (@ (class "col-md-4")) "Version")
+          (th (@ (class "col-md-4")) "")))
         (tbody
          ,@(map
             (match-lambda
-              ((name version rest ...)
+              ((name version)
                `(tr
                  (td ,name)
-                 (td ,version))))
-            (vlist->list base-packages-vhash)))))
+                 (td ,version)
+                 (td (@ (class "text-right"))
+                     (a (@ (href ,(string-append
+                                   "/revision/" base-commit
+                                   "/package/" name "/" version)))
+                        "More information")))))
+            (delete-duplicates
+             (map (lambda (data)
+                    (take data 2))
+                  (vlist->list base-packages-vhash)))))))
       (div
        (@ (class "row"))
        (h3 "Target ("
@@ -658,16 +831,25 @@
         (@ (class "table"))
         (thead
          (tr
-          (th (@ (class "col-md-6")) "Name")
-          (th (@ (class "col-md-6")) "Version")))
+          (th (@ (class "col-md-4")) "Name")
+          (th (@ (class "col-md-4")) "Version")
+          (th (@ (class "col-md-4")) "")))
         (tbody
          ,@(map
             (match-lambda
-              ((name version rest ...)
+              ((name version)
                `(tr
                  (td ,name)
-                 (td ,version))))
-            (vlist->list target-packages-vhash)))))))))
+                 (td ,version)
+                 (td (@ (class "text-right"))
+                     (a (@ (href ,(string-append
+                                   "/revision/" base-commit
+                                   "/package/" name "/" version)))
+                        "More information")))))
+            (delete-duplicates
+             (map (lambda (data)
+                    (take data 2))
+                  (vlist->list target-packages-vhash)))))))))))
 
 (define (compare-unknown-commit base-commit target-commit
                                 base-exists? target-exists?