Docker command not found

# Use Rust docker image
image: docker:latest

services:
  - docker:dind

before_script:
  - echo $DOCKER_PASSWORD | docker login -u matrix1986 --password-stdin

# Defines stages which are to be executed
stages:
  - build

run-build:
  when: manual
  stage: build
  image: matrix1986/rust:rustc-nightly
  variables:
    POSTGRES_DB: hds
    POSTGRES_USER: runner
    POSTGRES_PASSWORD: ""
  services:
    - docker:dind
    - postgres:latest
  variables:
    DATABASE_URL: "postgres://runner@postgres/hds"
  script:
  - diesel setup
  - diesel print-schema > src/schema.rs
  - rustc --version
  - cargo build --release
  - docker build -t matrix1986/cloudscale:hds-0.1 .
  - docker push matrix1986/cloudscale:hds-0.1

the cargo build will compile the project, the compile dependence postgres, and then i want docker build the result