Hi,

just to make the report reproducible, I'm using a docker file. This dockerfile works (with ruby-2.7):

FROM ruby:2-alpine

RUN apk add --update --upgrade --no-cache --virtual .build-dependencies gcc musl-dev make sqlite-dev &&
gem install gemstash &&
apk del .build-dependencies &&
rm -rf /var/cache/apk/*

CMD ["gemstash","start","--no-daemonize"]

But when replacing the FROM image with ruby:alpine (i.e. using ruby 3) it still compiles,yet the process results in

/usr/local/bundle/gems/gemstash-2.1.0/lib/gemstash/web.rb:10:in initialize': wrong number of arguments (given 1, expected 0) (ArgumentError) from /usr/local/bundle/gems/sinatra-2.1.0/lib/sinatra/base.rb:1527:in new'
[...]

regards