g++/gcc/make not found in remote docker

Hi,

I've run into a problem where I cannot get a docker toolchain to find gcc/g++/make when deployed on a remote machine but it works when the the docker is local. To simplify the debug, I proceeded with a simple docker:

FROM ubuntu:18.04

RUN apt-get update \
  && apt-get install -y ssh \
    build-essential \
    gcc \
    g++ \
    gdb \
    clang \
    cmake \
    rsync \
    tar \
    python \
  && apt-get clean

RUN useradd -m user && yes password | passwd user

Build:

docker build -t clion/remote-cpp-env:0.5 -f Dockerfile.remote-cpp-env .

https://blog.jetbrains.com/clion/2020/01/using-docker-with-clion/ 

Result:

local machine: cmake/make/gcc/g++/debugger are all found (ssh into local machine for docker connection)

ubuntu1 remote machine: cmake/debugger are found -- make/gcc/g++ not found (ssh into remote machine for docker connection)

ubuntu1 remote machine with defined paths: cmake/debugger are found -- CMake run test fails (ssh into remote machine for docker connection)

Double check of locations:

I don't understand how it finds cmake but not the others. I'm thinking this has something to do with user permissions? Any ideas?

Thanks