Problems installing Jekyll on Linux

Hi community,
I am new to Linux and new to Jekyll, but have a long experiance in creating/developing Websites with PHP-based CMS. Could you please help me to fix this problem. The main problem seems to be Ruby. I installed Ruby on my Linux machine and the version seems to be OK. Nevertheless if I try to install Jekyll I receive an error message. I am now in five different groups, including this one and try it since two days, but there is no result. Can anybody please help me?

Here is what I have:
sudo gem install jekyll bundler
[sudo] password for raphael:
Building native extensions. This could take a while…
ERROR: Error installing jekyll:
ERROR: Failed to build gem native extension.

current directory: /var/lib/gems/2.5.0/gems/eventmachine-1.2.7/ext

/usr/bin/ruby2.5 -r ./siteconf20201118-3954-10gesi2.rb extconf.rb
checking for -lcrypto… *** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers. Check the mkmf.log file for more details. You may
need configuration options.

Provided configuration options:
–without-opt-include={opt-dir}/include --with-opt-lib --without-opt-lib={opt-dir}/lib
–ruby=/usr/bin/(RUBY_BASE_NAME)2.5 --with-ssl-dir --without-ssl-dir --with-ssl-include --without-ssl-include={ssl-dir}/include
/usr/lib/ruby/2.5.0/mkmf.rb:456:in try_do': The compiler failed to generate an executable file. (RuntimeError) You have to install development tools first. from /usr/lib/ruby/2.5.0/mkmf.rb:541:in try_link0’
from /usr/lib/ruby/2.5.0/mkmf.rb:559:in try_link' from /usr/lib/ruby/2.5.0/mkmf.rb:777:in try_func’
from /usr/lib/ruby/2.5.0/mkmf.rb:1004:in block in have_library' from /usr/lib/ruby/2.5.0/mkmf.rb:947:in block in checking_for’
from /usr/lib/ruby/2.5.0/mkmf.rb:350:in block (2 levels) in postpone' from /usr/lib/ruby/2.5.0/mkmf.rb:320:in open’
from /usr/lib/ruby/2.5.0/mkmf.rb:350:in block in postpone' from /usr/lib/ruby/2.5.0/mkmf.rb:320:in open’
from /usr/lib/ruby/2.5.0/mkmf.rb:346:in postpone' from /usr/lib/ruby/2.5.0/mkmf.rb:946:in checking_for’
from /usr/lib/ruby/2.5.0/mkmf.rb:999:in have_library' from extconf.rb:8:in block in check_libs’
from extconf.rb:8:in each' from extconf.rb:8:in all?’
from extconf.rb:8:in check_libs' from extconf.rb:95:in

To see why this extension failed to compile, please check the mkmf.log which can be found here:


extconf failed, exit code 1

Gem files will remain installed in /var/lib/gems/2.5.0/gems/eventmachine-1.2.7 for inspection.
Results logged to /var/lib/gems/2.5.0/extensions/x86_64-linux/2.5.0/eventmachine-1.2.7/gem_make.out
Successfully installed bundler-2.1.4
Parsing documentation for bundler-2.1.4
Done installing documentation for bundler after 5 seconds
1 gem installed

What does that mean?
any ideas?

The error messages are cryptic, but one of the first ones is: (RuntimeError) You have to install development tools first.

Double-check that all the necessary packages are installed. Here’s the doc for Ubuntu (or see other Linux doc):