diff --git a/maven-plugin-bundle.spec b/maven-plugin-bundle.spec
index 40d1732..12bf068 100644
--- a/maven-plugin-bundle.spec
+++ b/maven-plugin-bundle.spec
@@ -22,7 +22,7 @@ Release:        0
 Summary:        Maven Bundle Plugin
 License:        Apache-2.0
 Group:          Development/Libraries/Java
-URL:            http://felix.apache.org
+URL:            https://felix.apache.org
 Source0:        https://repo1.maven.org/maven2/org/apache/felix/maven-bundle-plugin/%{version}/maven-bundle-plugin-%{version}-source-release.tar.gz
 BuildRequires:  fdupes
 BuildRequires:  maven-local
@@ -36,6 +36,7 @@ BuildRequires:  mvn(org.apache.maven:maven-archiver)
 BuildRequires:  mvn(org.apache.maven:maven-compat)
 BuildRequires:  mvn(org.apache.maven:maven-core)
 BuildRequires:  mvn(org.codehaus.plexus:plexus-utils)
+BuildRequires:  mvn(org.slf4j:slf4j-api)
 BuildRequires:  mvn(org.sonatype.plexus:plexus-build-api)
 
 %description
@@ -73,7 +74,7 @@ rm -f src/main/java/org/apache/felix/bundleplugin/baseline/BaselineReport.java
 
 %build
 # Tests depend on bundled JARs
-%mvn_build -f -- -Dsource=8
+%{mvn_build} -f -- -Dsource=8
 
 %install
 %mvn_install