1. Run alpine docker (change --platform to corresponding architecture you want): 
      docker run --platform=linux/arm/v7 --name altserver-builder-alpine-armv7 -it alpine:3.15 
  2. Install dependencies:
      apk add zsh git curl wget g++ clang boost-static ninja boost-dev cmake make sudo bash vim libressl-dev util-linux-dev zlib-dev zlib-static
  3. Install corecrypto
      download corecrypto from apple website, unzip corecrypto.zip; cd corecrypto; mkdir build; cd build; CC=clang CXX=clang++ cmake ..;
      vim CMakeFiles/Makefile2, delete line starts with "all: corecrypto_perf/....." and "all: corecrypto_test/.....", then make; make install
  4. Install cpprestsdk
      git clone --recursive https://github.com/microsoft/cpprestsdk; cd cpprestsdk; mkdir build; cmake -DBUILD_SHARED_LIBS=0 ..; make; make install
      (if you're compiling for armv7, you have to grep -Wcast-align, and remove it, or the compiling would fail)
  5. Install libzip
      git clone https://github.com/nih-at/libzip; cd libzip; mkdir build; cd build; cmake -DBUILD_SHARED_LIBS=0 ..; make; make install
  6. Compile AltServer-Linux
      git clone --recursive https://github.com/NyaMisty/AltServer-Linux
      cd AltServer-Linux
      make -f ../Makefile -j3
      (if you're compiling for ARM, i.e. armv7 or aarch64, you'll have to remove the -mno-default flag in Makefile)