diff --git a/src/lib/Hydra/Controller/Build.pm b/src/lib/Hydra/Controller/Build.pm
index c3869838..6b25ff80 100644
--- a/src/lib/Hydra/Controller/Build.pm
+++ b/src/lib/Hydra/Controller/Build.pm
@@ -15,6 +15,7 @@ use Nix::Config;
 use List::SomeUtils qw(all);
 use Encode;
 use JSON::PP;
+use WWW::Form::UrlEncoded::PP qw();
 
 use feature 'state';
 
@@ -141,7 +142,7 @@ sub view_nixlog : Chained('buildChain') PathPart('nixlog') {
     $c->stash->{step} = $step;
 
     my $drvPath = $step->drvpath;
-    my $log_uri = $c->uri_for($c->controller('Root')->action_for("log"), [basename($drvPath)]);
+    my $log_uri = $c->uri_for($c->controller('Root')->action_for("log"), [WWW::Form::UrlEncoded::PP::url_encode(basename($drvPath))]);
     showLog($c, $mode, $log_uri);
 }
 
@@ -150,7 +151,7 @@ sub view_log : Chained('buildChain') PathPart('log') {
     my ($self, $c, $mode) = @_;
 
     my $drvPath = $c->stash->{build}->drvpath;
-    my $log_uri = $c->uri_for($c->controller('Root')->action_for("log"), [basename($drvPath)]);
+    my $log_uri = $c->uri_for($c->controller('Root')->action_for("log"), [WWW::Form::UrlEncoded::PP::url_encode(basename($drvPath))]);
     showLog($c, $mode, $log_uri);
 }
 
diff --git a/src/lib/Hydra/Controller/Root.pm b/src/lib/Hydra/Controller/Root.pm
index 548cfac3..e6c3049f 100644
--- a/src/lib/Hydra/Controller/Root.pm
+++ b/src/lib/Hydra/Controller/Root.pm
@@ -16,6 +16,7 @@ use List::Util qw[min max];
 use List::SomeUtils qw{any};
 use Net::Prometheus;
 use Types::Standard qw/StrMatch/;
+use WWW::Form::UrlEncoded::PP qw();
 
 use constant NARINFO_REGEX => qr{^([a-z0-9]{32})\.narinfo$};
 # e.g.: https://hydra.example.com/realisations/sha256:a62128132508a3a32eef651d6467695944763602f226ac630543e947d9feb140!out.doi
@@ -553,7 +554,7 @@ sub log :Local :Args(1) {
     my $logPrefix = $c->config->{log_prefix};
 
     if (defined $logPrefix) {
-        $c->res->redirect($logPrefix . "log/" . basename($drvPath));
+        $c->res->redirect($logPrefix . "log/" . WWW::Form::UrlEncoded::PP::url_encode(basename($drvPath)));
     } else {
         notFound($c, "The build log of $drvPath is not available.");
     }