ultra-tiny 1kB docker images

.gitignore

*.o
hello

README.md

Ultra-tiny 1kB Docker Image

$ docker images |grep tiny-hello
tiny-hello                                    latest                21d5b79018bb        2 minutes ago       952B

Dockerfile

FROM alpine:latest as builder
WORKDIR /build
RUN apk update && \
    apk add nasm make binutils
COPY .  ./
RUN make hello

FROM scratch
WORKDIR /
COPY --from=builder /build/hello .
CMD ["/hello"]

hello.asm

; Define variables in the data section
SECTION .DATA
	hello:     db 'Hello world!',10
	helloLen:  equ $-hello

; Code goes in the text section
SECTION .TEXT
	GLOBAL _start 

_start:
	mov eax,4            ; 'write' system call = 4
	mov ebx,1            ; file descriptor 1 = STDOUT
	mov ecx,hello        ; string to write
	mov edx,helloLen     ; length of string to write
	int 80h              ; call the kernel

	; Terminate program
	mov eax,1            ; 'exit' system call
	mov ebx,0            ; exit with error code 0
	int 80h              ; call the kernel

Makefile

hello.o: hello.asm
	nasm -f elf64 $< -o $@

hello: hello.o
	ld $< -o $@