diff --git a/nix/sources.json b/nix/sources.json
index e98d9d1..2247067 100644
--- a/nix/sources.json
+++ b/nix/sources.json
@@ -2,12 +2,13 @@
     "nixpkgs": {
         "branch": "nixos-19.03",
         "description": "Nixpkgs/NixOS branches that track the Nixpkgs/NixOS channels",
+        "homepage": "https://github.com/NixOS/nixpkgs",
         "owner": "NixOS",
         "repo": "nixpkgs-channels",
-        "rev": "8634c3b619909db7fc747faf8c03592986626e21",
-        "sha256": "0hcpy4q64vbqmlmnfcavfxilyygyzpwdsss8g3p73ikpic0j6ziq",
+        "rev": "5b0b58685d68b9c9c12132f7b392c9dcdecc5931",
+        "sha256": "1fy1ghl79p3w1vg0hnakvrb1lqic4mjrwmylcgqa5bd4ilfrirzf",
         "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs-channels/archive/8634c3b619909db7fc747faf8c03592986626e21.tar.gz",
+        "url": "https://github.com/NixOS/nixpkgs-channels/archive/5b0b58685d68b9c9c12132f7b392c9dcdecc5931.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "termtosvg": {
@@ -16,10 +17,10 @@
         "homepage": "https://nbedos.github.io/termtosvg/",
         "owner": "nbedos",
         "repo": "termtosvg",
-        "rev": "525330d7d3d7f55b9ed2344140b9b320552a97a4",
-        "sha256": "07y39kyabsz88vrf37chcb0d4s5d6knyg95xmq5787vp987f5ii0",
+        "rev": "b97cc0132073111cec37f64c95539e869202ff99",
+        "sha256": "1c86622sda98zm3q3dzwmm37i09yca661kn860svl191nqbh2l68",
         "type": "tarball",
-        "url": "https://github.com/nbedos/termtosvg/archive/525330d7d3d7f55b9ed2344140b9b320552a97a4.tar.gz",
+        "url": "https://github.com/nbedos/termtosvg/archive/b97cc0132073111cec37f64c95539e869202ff99.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     }
 }
diff --git a/script/update b/script/update
new file mode 100755
index 0000000..17ea880
--- /dev/null
+++ b/script/update
@@ -0,0 +1,7 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -I nixpkgs=./nix
+#!nix-shell -i bash -p cabal-install -p nix -p curl --pure
+#!nix-shell --keep SSL_CERT_FILE
+# vim: filetype=sh
+
+$(nix-build -A niv)/bin/niv update
diff --git a/site/niv.svg b/site/niv.svg
index faaecce..f188355 100644
--- a/site/niv.svg
+++ b/site/niv.svg
@@ -21,14 +21,14 @@
 
             @keyframes roll {
                 0.000%{transform:translateY(0px)}
-28.571%{transform:translateY(-442px)}
-57.143%{transform:translateY(-884px)}
-85.714%{transform:translateY(-1326px)}
-100.000%{transform:translateY(-1326px)}
+28.571%{transform:translateY(-476px)}
+57.143%{transform:translateY(-952px)}
+85.714%{transform:translateY(-1428px)}
+100.000%{transform:translateY(-1428px)}
             }
 
             #screen_view {
-                animation-duration: var(--animation-duration);
+                animation-duration: 7000ms;
                 animation-iteration-count:infinite;
                 animation-name:roll;
                 animation-timing-function: steps(1,end);
@@ -58,5 +58,5 @@
         </style>
     </defs>
     <svg id="screen" width="656" height="442" viewBox="0 0 656 442" preserveAspectRatio="xMidYMin slice">
-        <rect class="background" height="100%" width="100%" x="0" y="0"/><defs><g id="g1"><text class="foreground" textLength="80" x="0">$ niv init</text></g><g id="g2"><text class="color15" font-weight="bold" textLength="96" x="0">Initializing</text></g><g id="g3"><text class="foreground" textLength="208" x="0">  Creating nix/sources.nix</text></g><g id="g4"><text class="foreground" textLength="216" x="0">  Creating nix/sources.json</text></g><g id="g5"><text class="foreground" textLength="168" x="0">  Importing 'niv' ...</text></g><g id="g6"><text class="foreground" textLength="16" x="0">  </text><text class="color15" font-weight="bold" textLength="208" x="16">Adding package nmattia/niv</text></g><g id="g7"><text class="foreground" textLength="192" x="0">    Reading sources file</text></g><g id="g8"><text class="background" textLength="8" x="0"> </text></g><g id="g9"><text class="foreground" textLength="224" x="0">    Writing new sources file</text></g><g id="g10"><text class="foreground" textLength="16" x="0">  </text><text class="color10" font-weight="bold" textLength="32" x="16">Done</text><text class="foreground" textLength="224" x="48">: Adding package nmattia/niv</text></g><g id="g11"><text class="foreground" textLength="200" x="0">  Importing 'nixpkgs' ...</text></g><g id="g12"><text class="foreground" textLength="16" x="0">  </text><text class="color15" font-weight="bold" textLength="296" x="16">Adding package NixOS/nixpkgs-channels</text></g><g id="g13"><text class="foreground" textLength="16" x="0">  </text><text class="color10" font-weight="bold" textLength="32" x="16">Done</text><text class="foreground" textLength="312" x="48">: Adding package NixOS/nixpkgs-channels</text></g><g id="g14"><text class="color10" font-weight="bold" textLength="32" x="0">Done</text><text class="foreground" textLength="112" x="32">: Initializing</text></g><g id="g15"><text class="foreground" textLength="168" x="0">$ niv add stedolan/jq</text></g><g id="g16"><text class="color15" font-weight="bold" textLength="208" x="0">Adding package stedolan/jq</text></g><g id="g17"><text class="foreground" textLength="176" x="0">  Reading sources file</text></g><g id="g18"><text class="foreground" textLength="208" x="0">  Writing new sources file</text></g><g id="g19"><text class="color10" font-weight="bold" textLength="32" x="0">Done</text><text class="foreground" textLength="224" x="32">: Adding package stedolan/jq</text></g></defs><g id="screen_view"><g><use y="0" xlink:href="#g1"/><use y="17" xlink:href="#g2"/><use y="34" xlink:href="#g3"/><use y="51" xlink:href="#g4"/><use y="68" xlink:href="#g5"/><use y="85" xlink:href="#g6"/><use y="102" xlink:href="#g7"/><rect class="foreground" height="17" width="8" x="0" y="119"/><use y="119" xlink:href="#g8"/></g><g><use y="442" xlink:href="#g1"/><use y="459" xlink:href="#g2"/><use y="476" xlink:href="#g3"/><use y="493" xlink:href="#g4"/><use y="510" xlink:href="#g5"/><use y="527" xlink:href="#g6"/><use y="544" xlink:href="#g7"/><use y="561" xlink:href="#g9"/><use y="578" xlink:href="#g10"/><use y="595" xlink:href="#g11"/><use y="612" xlink:href="#g12"/><use y="629" xlink:href="#g7"/><rect class="foreground" height="17" width="8" x="0" y="646"/><use y="646" xlink:href="#g8"/></g><g><use y="884" xlink:href="#g1"/><use y="901" xlink:href="#g2"/><use y="918" xlink:href="#g3"/><use y="935" xlink:href="#g4"/><use y="952" xlink:href="#g5"/><use y="969" xlink:href="#g6"/><use y="986" xlink:href="#g7"/><use y="1003" xlink:href="#g9"/><use y="1020" xlink:href="#g10"/><use y="1037" xlink:href="#g11"/><use y="1054" xlink:href="#g12"/><use y="1071" xlink:href="#g7"/><use y="1088" xlink:href="#g9"/><use y="1105" xlink:href="#g13"/><use y="1122" xlink:href="#g14"/><use y="1156" xlink:href="#g15"/><use y="1173" xlink:href="#g16"/><use y="1190" xlink:href="#g17"/><rect class="foreground" height="17" width="8" x="0" y="1207"/><use y="1207" xlink:href="#g8"/></g><g><use y="1326" xlink:href="#g1"/><use y="1343" xlink:href="#g2"/><use y="1360" xlink:href="#g3"/><use y="1377" xlink:href="#g4"/><use y="1394" xlink:href="#g5"/><use y="1411" xlink:href="#g6"/><use y="1428" xlink:href="#g7"/><use y="1445" xlink:href="#g9"/><use y="1462" xlink:href="#g10"/><use y="1479" xlink:href="#g11"/><use y="1496" xlink:href="#g12"/><use y="1513" xlink:href="#g7"/><use y="1530" xlink:href="#g9"/><use y="1547" xlink:href="#g13"/><use y="1564" xlink:href="#g14"/><use y="1598" xlink:href="#g15"/><use y="1615" xlink:href="#g16"/><use y="1632" xlink:href="#g17"/><use y="1649" xlink:href="#g18"/><use y="1666" xlink:href="#g19"/><rect class="foreground" height="17" width="8" x="0" y="1683"/><use y="1683" xlink:href="#g8"/></g></g></svg>
+        <rect class="background" height="100%" width="100%" x="0" y="0"/><defs><g id="g1"><text class="foreground" textLength="80" x="0">$ niv init</text></g><g id="g2"><text class="color15" font-weight="bold" textLength="96" x="0">Initializing</text></g><g id="g3"><text class="foreground" textLength="208" x="0">  Creating nix/sources.nix</text></g><g id="g4"><text class="foreground" textLength="216" x="0">  Creating nix/sources.json</text></g><g id="g5"><text class="foreground" textLength="168" x="0">  Importing 'niv' ...</text></g><g id="g6"><text class="foreground" textLength="16" x="0">  </text><text class="color15" font-weight="bold" textLength="208" x="16">Adding package nmattia/niv</text></g><g id="g7"><text class="foreground" textLength="192" x="0">    Reading sources file</text></g><g id="g8"><text class="background" textLength="8" x="0"> </text></g><g id="g9"><text class="foreground" textLength="224" x="0">    Writing new sources file</text></g><g id="g10"><text class="foreground" textLength="16" x="0">  </text><text class="color10" font-weight="bold" textLength="32" x="16">Done</text><text class="foreground" textLength="224" x="48">: Adding package nmattia/niv</text></g><g id="g11"><text class="foreground" textLength="200" x="0">  Importing 'nixpkgs' ...</text></g><g id="g12"><text class="foreground" textLength="16" x="0">  </text><text class="color15" font-weight="bold" textLength="296" x="16">Adding package NixOS/nixpkgs-channels</text></g><g id="g13"><text class="foreground" textLength="16" x="0">  </text><text class="color10" font-weight="bold" textLength="32" x="16">Done</text><text class="foreground" textLength="312" x="48">: Adding package NixOS/nixpkgs-channels</text></g><g id="g14"><text class="color10" font-weight="bold" textLength="32" x="0">Done</text><text class="foreground" textLength="112" x="32">: Initializing</text></g><g id="g15"><text class="foreground" textLength="168" x="0">$ niv add stedolan/jq</text></g><g id="g16"><text class="color15" font-weight="bold" textLength="208" x="0">Adding package stedolan/jq</text></g><g id="g17"><text class="foreground" textLength="176" x="0">  Reading sources file</text></g><g id="g18"><text class="foreground" textLength="208" x="0">  Writing new sources file</text></g><g id="g19"><text class="color10" font-weight="bold" textLength="32" x="0">Done</text><text class="foreground" textLength="224" x="32">: Adding package stedolan/jq</text></g></defs><g id="screen_view"><g><use y="0" xlink:href="#g1"/><use y="17" xlink:href="#g2"/><use y="34" xlink:href="#g3"/><use y="51" xlink:href="#g4"/><use y="68" xlink:href="#g5"/><use y="85" xlink:href="#g6"/><use y="102" xlink:href="#g7"/><rect class="foreground" height="17" width="8" x="0" y="119"/><use y="119" xlink:href="#g8"/></g><g><use y="476" xlink:href="#g1"/><use y="493" xlink:href="#g2"/><use y="510" xlink:href="#g3"/><use y="527" xlink:href="#g4"/><use y="544" xlink:href="#g5"/><use y="561" xlink:href="#g6"/><use y="578" xlink:href="#g7"/><use y="595" xlink:href="#g9"/><use y="612" xlink:href="#g10"/><use y="629" xlink:href="#g11"/><use y="646" xlink:href="#g12"/><use y="663" xlink:href="#g7"/><rect class="foreground" height="17" width="8" x="0" y="680"/><use y="680" xlink:href="#g8"/></g><g><use y="952" xlink:href="#g1"/><use y="969" xlink:href="#g2"/><use y="986" xlink:href="#g3"/><use y="1003" xlink:href="#g4"/><use y="1020" xlink:href="#g5"/><use y="1037" xlink:href="#g6"/><use y="1054" xlink:href="#g7"/><use y="1071" xlink:href="#g9"/><use y="1088" xlink:href="#g10"/><use y="1105" xlink:href="#g11"/><use y="1122" xlink:href="#g12"/><use y="1139" xlink:href="#g7"/><use y="1156" xlink:href="#g9"/><use y="1173" xlink:href="#g13"/><use y="1190" xlink:href="#g14"/><use y="1224" xlink:href="#g15"/><use y="1241" xlink:href="#g16"/><use y="1258" xlink:href="#g17"/><rect class="foreground" height="17" width="8" x="0" y="1275"/><use y="1275" xlink:href="#g8"/></g><g><use y="1428" xlink:href="#g1"/><use y="1445" xlink:href="#g2"/><use y="1462" xlink:href="#g3"/><use y="1479" xlink:href="#g4"/><use y="1496" xlink:href="#g5"/><use y="1513" xlink:href="#g6"/><use y="1530" xlink:href="#g7"/><use y="1547" xlink:href="#g9"/><use y="1564" xlink:href="#g10"/><use y="1581" xlink:href="#g11"/><use y="1598" xlink:href="#g12"/><use y="1615" xlink:href="#g7"/><use y="1632" xlink:href="#g9"/><use y="1649" xlink:href="#g13"/><use y="1666" xlink:href="#g14"/><use y="1700" xlink:href="#g15"/><use y="1717" xlink:href="#g16"/><use y="1734" xlink:href="#g17"/><use y="1751" xlink:href="#g18"/><use y="1768" xlink:href="#g19"/><rect class="foreground" height="17" width="8" x="0" y="1785"/><use y="1785" xlink:href="#g8"/></g></g></svg>
 </svg>
\ No newline at end of file