Question on native executable dependencies

Hello everyone,

I am new to OCaml and I am currently testing some small programs just to see how I could use it.

In that process, I have written a basic program that fetches a web page from a given url, and I have come up with this (using the ezcurl package):

open Ezcurl

let url = "https://info.cern.ch/"

let () =
  let res = Ezcurl.get ~url () in
  let output = (match res with
  | Ok response -> response.body
  | Error (_,s) -> "Error: " ^ s) in
  print_endline ("Result:\n" ^ output)

The program works as expected (it compiles and runs fine as a native executable). The thing is, I had a look at the executable dependencies and here’s what I got:

$ ldd _build/default/test_curl.exe
        linux-vdso.so.1 (0x00007ffd749f7000)
        libcurl-gnutls.so.4 => /lib/x86_64-linux-gnu/libcurl-gnutls.so.4 (0x00007fd8e38d4000)
        libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007fd8e37f5000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fd8e3614000)
        libnghttp2.so.14 => /lib/x86_64-linux-gnu/libnghttp2.so.14 (0x00007fd8e35e5000)
        libidn2.so.0 => /lib/x86_64-linux-gnu/libidn2.so.0 (0x00007fd8e35b4000)
        librtmp.so.1 => /lib/x86_64-linux-gnu/librtmp.so.1 (0x00007fd8e3593000)
        libssh2.so.1 => /lib/x86_64-linux-gnu/libssh2.so.1 (0x00007fd8e3552000)
        libpsl.so.5 => /lib/x86_64-linux-gnu/libpsl.so.5 (0x00007fd8e353e000)
        libnettle.so.8 => /lib/x86_64-linux-gnu/libnettle.so.8 (0x00007fd8e34f0000)
        libgnutls.so.30 => /lib/x86_64-linux-gnu/libgnutls.so.30 (0x00007fd8e32d4000)
        libgssapi_krb5.so.2 => /lib/x86_64-linux-gnu/libgssapi_krb5.so.2 (0x00007fd8e3282000)
        libldap-2.5.so.0 => /lib/x86_64-linux-gnu/libldap-2.5.so.0 (0x00007fd8e3221000)
        liblber-2.5.so.0 => /lib/x86_64-linux-gnu/liblber-2.5.so.0 (0x00007fd8e3211000)
        libzstd.so.1 => /lib/x86_64-linux-gnu/libzstd.so.1 (0x00007fd8e3155000)
        libbrotlidec.so.1 => /lib/x86_64-linux-gnu/libbrotlidec.so.1 (0x00007fd8e3148000)
        libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007fd8e3129000)
        /lib64/ld-linux-x86-64.so.2 (0x00007fd8e3b22000)
        libunistring.so.2 => /lib/x86_64-linux-gnu/libunistring.so.2 (0x00007fd8e2f71000)
        libhogweed.so.6 => /lib/x86_64-linux-gnu/libhogweed.so.6 (0x00007fd8e2f28000)
        libgmp.so.10 => /lib/x86_64-linux-gnu/libgmp.so.10 (0x00007fd8e2ea7000)
        libcrypto.so.3 => /lib/x86_64-linux-gnu/libcrypto.so.3 (0x00007fd8e2a25000)
        libp11-kit.so.0 => /lib/x86_64-linux-gnu/libp11-kit.so.0 (0x00007fd8e28f1000)
        libtasn1.so.6 => /lib/x86_64-linux-gnu/libtasn1.so.6 (0x00007fd8e28da000)
        libkrb5.so.3 => /lib/x86_64-linux-gnu/libkrb5.so.3 (0x00007fd8e2800000)
        libk5crypto.so.3 => /lib/x86_64-linux-gnu/libk5crypto.so.3 (0x00007fd8e27d3000)
        libcom_err.so.2 => /lib/x86_64-linux-gnu/libcom_err.so.2 (0x00007fd8e27cd000)
        libkrb5support.so.0 => /lib/x86_64-linux-gnu/libkrb5support.so.0 (0x00007fd8e27bf000)
        libsasl2.so.2 => /lib/x86_64-linux-gnu/libsasl2.so.2 (0x00007fd8e27a0000)
        libbrotlicommon.so.1 => /lib/x86_64-linux-gnu/libbrotlicommon.so.1 (0x00007fd8e277d000)
        libffi.so.8 => /lib/x86_64-linux-gnu/libffi.so.8 (0x00007fd8e2771000)
        libkeyutils.so.1 => /lib/x86_64-linux-gnu/libkeyutils.so.1 (0x00007fd8e276a000)
        libresolv.so.2 => /lib/x86_64-linux-gnu/libresolv.so.2 (0x00007fd8e2759000)

I guess it’s normal but I was somewhat surprised by the number of dependencies.
My question is: is there a known method to reduce these somehow (like static linking or other mechanism) ?

I am not too worried by this at this stage, it’s just that I’m wondering about portability in case of deployment of my executable to another Linux box.

Thanks in advance,

My environment:

$ uname -a
Linux 55e345739265 6.1.0-13-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.55-1 (2023-09-29) x86_64 GNU/Linux
$ ocamlopt --version
4.13.1
$ opam --version
2.1.2
$ dune --version
3.14.0
$ opam list
# Packages matching: installed
# Name        # Installed # Synopsis
base-bigarray base
base-threads  base
base-unix     base
conf-libcurl  2           Virtual package relying on a libcurl system installation
dune          3.14.0      Fast, portable, and opinionated build system
ezcurl        0.2.4       Friendly wrapper around OCurl
ocaml         4.13.1      The OCaml compiler (virtual package)
ocaml-config  2           OCaml Switch Configuration
ocaml-system  4.13.1      The OCaml compiler (system version, from outside of opam)
ocamlfind     1.9.6       A library manager for OCaml
ocurl         0.9.2       Bindings to libcurl

My dune file:

(executable
  (name test_curl)
  (libraries ezcurl)
  (modes byte native))

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