diff --git a/gnu/packages/emacs.scm b/gnu/packages/emacs.scm
index ec672bce8c..a5dd7a961f 100644
--- a/gnu/packages/emacs.scm
+++ b/gnu/packages/emacs.scm
@@ -3355,9 +3355,8 @@ This package contains the library database.")
     (source
      (origin
        (method url-fetch)
-       (uri (string-append
-             "http://download.savannah.gnu.org/releases/m17n/m17n-lib-"
-             version ".tar.gz"))
+       (uri (string-append "mirror://savannah/m17n/m17n-lib-"
+                           version ".tar.gz"))
        (sha256
         (base32 "10yv730i25g1rpzv6q49m6xn4p8fjm7jdwvik2h70sn8w3hm7f4f"))))
     (build-system gnu-build-system)
diff --git a/gnu/packages/games.scm b/gnu/packages/games.scm
index e8f848a07f..e6a970a22c 100644
--- a/gnu/packages/games.scm
+++ b/gnu/packages/games.scm
@@ -946,7 +946,7 @@ Protocol).")
     (source (origin
               (method url-fetch)
               (uri (string-append
-                    "http://downloads.sourceforge.net/project/extremetuxracer/releases/"
+                    "mirror://sourceforge/extremetuxracer/releases/"
                     version "/etr-" version ".tar.xz"))
               (sha256
                (base32
diff --git a/gnu/packages/gcc.scm b/gnu/packages/gcc.scm
index e190e508a7..c26cc4f497 100644
--- a/gnu/packages/gcc.scm
+++ b/gnu/packages/gcc.scm
@@ -45,7 +45,7 @@
 
 (define %gcc-infrastructure
   ;; Base URL for GCC's infrastructure.
-  "ftp://gcc.gnu.org/pub/gcc/infrastructure/")
+  "mirror://gcc/infrastructure/")
 
 (define (gcc-configure-flags-for-triplet target)
   "Return a list of additional GCC `configure' flags for TARGET, a GNU triplet.
diff --git a/gnu/packages/gtk.scm b/gnu/packages/gtk.scm
index 7fa7e12b1b..6a9e7cf4d2 100644
--- a/gnu/packages/gtk.scm
+++ b/gnu/packages/gtk.scm
@@ -1116,7 +1116,7 @@ extensive documentation, including API reference and a tutorial.")
     (source
      (origin
       (method url-fetch)
-      (uri (string-append "http://ftp.gnome.org/pub/GNOME/sources"
+      (uri (string-append "mirror://gnome/sources"
                           "/pygtk/" (version-major+minor version)
                           "/pygtk-" version ".tar.bz2"))
       (sha256
diff --git a/gnu/packages/perl.scm b/gnu/packages/perl.scm
index a044a32b32..ab6120142d 100644
--- a/gnu/packages/perl.scm
+++ b/gnu/packages/perl.scm
@@ -48,7 +48,7 @@
     (version "5.24.0")
     (source (origin
              (method url-fetch)
-             (uri (string-append "http://www.cpan.org/src/5.0/perl-"
+             (uri (string-append "mirror://cpan/src/5.0/perl-"
                                  version ".tar.gz"))
              (sha256
               (base32
diff --git a/gnu/packages/telephony.scm b/gnu/packages/telephony.scm
index 8f2a10f2c5..3d5e58ec2d 100644
--- a/gnu/packages/telephony.scm
+++ b/gnu/packages/telephony.scm
@@ -134,9 +134,8 @@ to initiate and control SIP sessions.")
    (version "4.1.0")
    (source (origin
             (method url-fetch)
-            (uri (string-append
-                  "http://download.savannah.gnu.org/releases/exosip/libeXosip2-"
-                  version ".tar.gz"))
+            (uri (string-append "mirror://savannah/exosip/libeXosip2-"
+                                version ".tar.gz"))
             (sha256 (base32
                      "17cna8kpc8nk1si419vgr6r42k2lda0rdk50vlxrw8rzg0xp2xrw"))))
    (build-system gnu-build-system)
diff --git a/gnu/packages/wm.scm b/gnu/packages/wm.scm
index 90d1dc1e33..999f78927f 100644
--- a/gnu/packages/wm.scm
+++ b/gnu/packages/wm.scm
@@ -299,7 +299,7 @@ prompt.")
     (synopsis "Tiling window manager")
     (source (origin
               (method url-fetch)
-              (uri (string-append "http://hackage.haskell.org/package/xmonad/"
+              (uri (string-append "mirror://hackage/package/xmonad/"
                                   name "-" version ".tar.gz"))
               (sha256
                (base32
@@ -355,7 +355,7 @@ tiled on several screens.")
     (source
      (origin
        (method url-fetch)
-       (uri (string-append "http://hackage.haskell.org/package/xmonad-contrib/"
+       (uri (string-append "mirror://hackage/package/xmonad-contrib/"
                            "xmonad-contrib-" version ".tar.gz"))
        (sha256
         (base32