How is s3Client auto-wired in this project? - spring

Question

I'm writing a Spring application in which I want to use the AWS S3 client. All I need to do is generate signed URLs. The code that uses the S3 client is straightforward and I wrote it already, but I'm trying to figure out the proper way to instantiate it, as in, the Spring way.
I found this project on GitHub called spring-boot-aws that seems to do what I need. On FileArchiveService.java it has these two lines:
#Autowired
private AmazonS3Client s3Client;
When I add those lines to my project, I expectedly get this error:
Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'screenshotsController': Unsatisfied dependency expressed through field 's3Client'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.amazonaws.services.s3.AmazonS3Client' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {#org.springframework.beans.factory.annotation.Autowired(required=true)}
I searched spring-boot-aws trying to figure out how is this bean provided and I cannot find it. I'm including the same dependency, org.springframework.cloud:spring-cloud-aws-context:1.2.1.RELEASE but that's not enough.
Any ideas how that project is doing it or how I should do it?
I tried coping the aws-config.xml:
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aws-context="http://www.springframework.org/schema/cloud/aws/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.1.xsd
http://www.springframework.org/schema/cloud/aws/context
http://www.springframework.org/schema/cloud/aws/context/spring-cloud-aws-context-1.0.xsd">
<aws-context:context-credentials>
<aws-context:simple-credentials access-key="${accessKey:}" secret-key="${secretKey:}"/>
</aws-context:context-credentials>
<aws-context:context-resource-loader/>
</beans>
and a modified AwsResourceConfig.java:~
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.ImportResource;
#Configuration
#ImportResource("classpath:/aws-config.xml")
public class AwsResourceConfig {
}
but I still get the same error.