Merge changes I3c947080,I2a3d7e03,I3e0c834a,I5ed741b6

* changes:
  hswaw/cebulacamp: update ticket info, fix CSS
  cebulacamp: deploy
  third_party/go: fix vbom.ml dependency
  default.nix: bump nixpkgs
diff --git a/default.nix b/default.nix
index 4540157..6d9c0c4 100644
--- a/default.nix
+++ b/default.nix
@@ -7,11 +7,11 @@
 
   readTree = import ./nix/readtree.nix {};
 
-  # Tracking nixos-unstable as of 2021-01-31.
-  nixpkgsCommit = "44ad80ab1036c5cc83ada4bfa451dac9939f2a10";
+  # Tracking nixos-unstable as of 2021-08-11.
+  nixpkgsCommit = "e26c0ffdb013cd378fc2528a44689a8bf35d2a6c";
   nixpkgsSrc = fetchTarball {
     url = "https://github.com/NixOS/nixpkgs/archive/${nixpkgsCommit}.tar.gz";
-    sha256 = "1b61nzvy0d46cspy07szkc0rggacxiqg9v1py27pkqpj7rvawfsk";
+    sha256 = "1b33hw35fqb9rzszdg5jpiyfvhx2cxpv0qrkyr19zkdpdahzdbss";
   };
   nixpkgs = import nixpkgsSrc {
     config.allowUnfree = true;
diff --git a/hswaw/cebulacamp/landing/index.html b/hswaw/cebulacamp/landing/index.html
index 1385a31..31e7753 100644
--- a/hswaw/cebulacamp/landing/index.html
+++ b/hswaw/cebulacamp/landing/index.html
@@ -24,13 +24,13 @@
             <header>
                 <h2>Tickets</h2>
                 <p>
-                    If you already have tickets from 2020: they're still valid. We will also start another small round of ticket sales very soon.
+                    If you already have tickets from 2020: they're still valid. We also have some extra tickets for sale on our <a href="https://tickets.hackerspace.pl/cebulacamp/kkc20/1">ticket shop</a> available under September 1st. Get them while they're hot!
                 </p>
                 <p>
-                    The ticket shop is available at <a href="https://tickets.hackerspace.pl/cebulacamp/kkc20/1">tickets.hackerspace.pl/cebulacamp/kkc20/1</a>.
+                    <b>If you don't have a valid tickets.hackerspace.pl order marked as 'Paid', you <i>do not have a ticket</i>. If you paid the hotel and don't have an order marked as 'Paid', <a href="mailto:cebula@hackerspace.pl">get in touch with us ASAP</a>, or <i>we will not have a room for you.</i></b>
                 </p>
                 <p>
-                    An all-inclusive ticket (bed in shared room for two nights, food for three days) is 500 PLN. If you want a solo room, or to share a room with someone in particular, contact <a href="mailto:cebula@hackerspace.pl">cebula@hackerspace.pl</a>, or (once you bought your ticket) <a href="mailto:info@orle.pl">info@orle.com.pl</a>.
+                    An all-inclusive ticket (bed in shared room for two nights, food for three days) is 500 PLN. If you want a solo room, or to share a room with someone in particular, contact <a href="mailto:cebula@hackerspace.pl">cebula@hackerspace.pl</a>.
                 </p>
                 <p>
                     <img class="hotel-pic" src="hotel-orle.jpg">
diff --git a/hswaw/cebulacamp/landing/style/main.css b/hswaw/cebulacamp/landing/style/main.css
index 5668e45..8ed6d76 100644
--- a/hswaw/cebulacamp/landing/style/main.css
+++ b/hswaw/cebulacamp/landing/style/main.css
@@ -114,7 +114,7 @@
     border: 8px solid rgba(61, 140, 208, 1);;
 }
 
-section:nth-child(odd) h1 {
+section:nth-child(odd) h2 {
     background-color: rgba(61, 140, 208, 1);;
 }
 
diff --git a/hswaw/kube/cebulacamp.libsonnet b/hswaw/kube/cebulacamp.libsonnet
index 3380bdf..ffc7f1d 100644
--- a/hswaw/kube/cebulacamp.libsonnet
+++ b/hswaw/kube/cebulacamp.libsonnet
@@ -3,7 +3,7 @@
 
 {
     cfg:: {
-        image: "registry.k0.hswaw.net/q3k/cebulacamp-landing:315532800-f25fd84f02caf48122babfbd24acb3ce8a7979b0",
+        image: "registry.k0.hswaw.net/q3k/cebulacamp-landing:315532800-bbf56cf7e14df954dcddedfe44c967246f11b72c",
         webFQDN: error "webhookFQDN must be set",
     },
 
diff --git a/third_party/go/repositories.bzl b/third_party/go/repositories.bzl
index 12edfe1..2eb8499 100644
--- a/third_party/go/repositories.bzl
+++ b/third_party/go/repositories.bzl
@@ -84,9 +84,11 @@
     )
 
     go_repository(
-        name = "ml_vbom_util",
-        commit = "db5cfe13f5cc",
-        importpath = "vbom.ml/util",
+        name = "ml_vbom_util_sortorder",
+        commit = "26fad50c6b32a3064c09ed089865c16f2f3615f6",
+        importpath = "vbom.ml/util/sortorder",
+        remote = "https://github.com/fvbommel/sortorder",
+        vcs = "git",
     )
 
     go_repository(