Fix mutexes in the cacher

Dockerfile

@@ -0,0 +1,17 @@
+FROM docker.io/alpine AS builder
+
+LABEL maintainer="vladimir@hodakov.me"
+
+COPY . /src
+
+RUN apk add --no-cache go
+
+RUN cd /src && go build ./cmd/faketunes
+
+FROM docker.io/alpine
+
+RUN apk add --no-cache fuse3 ffmpeg
+
+COPY --from=builder /src/faketunes /bin/faketunes
+
+ENTRYPOINT [ "/bin/faketunes" ]