diff --git a/.github/workflows/push.yml b/.github/workflows/push.yml
index 4932ae8..d803cbc 100644
--- a/.github/workflows/push.yml
+++ b/.github/workflows/push.yml
@@ -15,7 +15,8 @@ jobs:
         build_cmd:
         - ./build-latest.sh
         - PRERELEASE=true ./build-latest.sh
-        - ./build-branches.sh
+        - ./build-next.sh
+        - ./build.sh develop
         docker_from:
         - '' # use the default of the DOCKERFILE
         - python:3.7-alpine
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 1796097..9dbf770 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -14,14 +14,15 @@ jobs:
         build_cmd:
         - ./build-latest.sh
         - PRERELEASE=true ./build-latest.sh
-        - ./build-branches.sh
+        - ./build-next.sh
+        - ./build.sh develop
       fail-fast: false
     runs-on: ubuntu-latest
     name: Builds new Netbox Docker Images
     steps:
     - id: git-checkout
       name: Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2
     - id: docker-build
       name: Build the image with '${{ matrix.build_cmd }}'
       run: ${{ matrix.build_cmd }}
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 99c5b53..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,32 +0,0 @@
-sudo: required
-language: python
-
-env:
-  - BUILD=release
-  - BUILD=prerelease
-  - BUILD=branches
-  - BUILD=special
-
-git:
-  depth: 5
-
-services:
-  - docker
-
-install:
-  - docker-compose pull --parallel
-  - docker-compose build
-
-script:
-  - docker-compose run netbox ./manage.py test
-
-after_script:
-  - docker-compose down
-
-after_success:
-  - docker login -u="$DOCKER_USERNAME" -p="$DOCKER_PASSWORD"
-  - ./build-all.sh --push
-
-notifications:
-  slack:
-    secure: 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
diff --git a/Dockerfile b/Dockerfile
index 2c83172..4347aa8 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-ARG FROM=python:3.7-alpine
+ARG FROM
 FROM ${FROM} as builder
 
 RUN apk add --no-cache \
diff --git a/build-all.sh b/build-all.sh
deleted file mode 100755
index 462a83a..0000000
--- a/build-all.sh
+++ /dev/null
@@ -1,51 +0,0 @@
-#!/bin/bash
-# Builds all Docker images this project provides
-# Arguments:
-#   BUILD:     The release to build.
-#              Allowed: release, prerelease, branches, special
-#              Default: undefined
-
-echo "▶️ $0 $*"
-
-ALL_BUILDS=("release" "prerelease" "branches" "special")
-BUILDS=("${BUILD:-"${ALL_BUILDS[@]}"}")
-
-echo "⚙️ Configured builds: ${BUILDS[*]}"
-
-if [ -n "${DEBUG}" ]; then
-  export DEBUG
-fi
-
-ERROR=0
-
-for BUILD in "${BUILDS[@]}"; do
-  echo "🛠 Building '$BUILD' from '$DOCKERFILE'"
-  case $BUILD in
-    release)
-      # build the latest release
-      # shellcheck disable=SC2068
-      ./build-latest.sh $@ || ERROR=1
-      ;;
-    prerelease)
-      # build the latest pre-release
-      # shellcheck disable=SC2068
-      PRERELEASE=true ./build-latest.sh $@ || ERROR=1
-      ;;
-    branches)
-      # build all branches
-      # shellcheck disable=SC2068
-      ./build-branches.sh $@ || ERROR=1
-      ;;
-    *)
-      echo "🚨 Unrecognized build '$BUILD'."
-
-      if [ -z "$DEBUG" ]; then
-        exit 1
-      else
-        echo "⚠️ Would exit here with code '1', but DEBUG is enabled."
-      fi
-      ;;
-  esac
-done
-
-exit $ERROR
diff --git a/build-functions/docker-functions.sh b/build-functions/docker-functions.sh
new file mode 100644
index 0000000..137ec54
--- /dev/null
+++ b/build-functions/docker-functions.sh
@@ -0,0 +1,8 @@
+#!/bin/bash
+
+push_image_to_registry() {
+  local target_tag=$1
+  echo "⏫ Pushing '${target_tag}'"
+  $DRY docker push "${target_tag}"
+  echo "✅ Finished pushing the Docker image '${target_tag}'."
+}
\ No newline at end of file
diff --git a/build-functions/get-public-image-config.sh b/build-functions/get-public-image-config.sh
new file mode 100644
index 0000000..f718716
--- /dev/null
+++ b/build-functions/get-public-image-config.sh
@@ -0,0 +1,82 @@
+#!/bin/bash
+# Retrieves image configuration from public images in DockerHub
+# Functions from https://gist.github.com/cirocosta/17ea17be7ac11594cb0f290b0a3ac0d1
+# Optimised for our use case
+
+get_image_label() {
+  local label=$1
+  local image=$2
+  local tag=$3
+  local token
+  token=$(_get_token "$image")
+  local digest
+  digest=$(_get_digest "$image" "$tag" "$token")
+  local retval="null"
+  if [ "$digest" != "null" ]; then
+    retval=$(_get_image_configuration "$image" "$token" "$digest" "$label")
+  fi
+  echo "$retval"
+}
+
+get_image_layers() {
+  local image=$1
+  local tag=$2
+  local token
+  token=$(_get_token "$image")
+  _get_layers "$image" "$tag" "$token"
+}
+
+get_image_last_layer() {
+  local image=$1
+  local tag=$2
+  local token
+  token=$(_get_token "$image")
+  local layers
+  mapfile -t layers < <(_get_layers "$image" "$tag" "$token")
+  echo "${layers[-1]}"
+}
+
+_get_image_configuration() {
+  local image=$1
+  local token=$2
+  local digest=$3
+  local label=$4
+  curl \
+    --silent \
+    --location \
+    --header "Authorization: Bearer $token" \
+    "https://registry-1.docker.io/v2/$image/blobs/$digest" \
+    | jq -r ".config.Labels.\"$label\""
+}
+
+_get_token() {
+  local image=$1
+  curl \
+    --silent \
+    "https://auth.docker.io/token?scope=repository:$image:pull&service=registry.docker.io" \
+    | jq -r '.token'
+}
+
+_get_digest() {
+  local image=$1
+  local tag=$2
+  local token=$3
+  curl \
+    --silent \
+    --header "Accept: application/vnd.docker.distribution.manifest.v2+json" \
+    --header "Authorization: Bearer $token" \
+    "https://registry-1.docker.io/v2/$image/manifests/$tag" \
+    | jq -r '.config.digest'
+}
+
+_get_layers() {
+  local image=$1
+  local tag=$2
+  local token=$3
+  curl \
+    --silent \
+    --header "Accept: application/vnd.docker.distribution.manifest.v2+json" \
+    --header "Authorization: Bearer $token" \
+    "https://registry-1.docker.io/v2/$image/manifests/$tag" \
+    | jq -r '.layers[].digest'
+}
diff --git a/build-branches.sh b/build-next.sh
similarity index 72%
rename from build-branches.sh
rename to build-next.sh
index 483e771..f134333 100755
--- a/build-branches.sh
+++ b/build-next.sh
@@ -23,25 +23,17 @@ GITHUB_REPO="${GITHUB_REPO-$ORIGINAL_GITHUB_REPO}"
 URL_RELEASES="https://api.github.com/repos/${GITHUB_REPO}/branches?${GITHUB_OAUTH_PARAMS}"
 
 # Composing the JQ commans to extract the most recent version number
-JQ_BRANCHES='map(.name) | .[] | scan("^[^v].+") | match("^(master|develop).*") | .string'
+JQ_NEXT='map(.name) | .[] | scan("^[^v].+") | match("^(develop-).*") | .string'
 
 CURL="curl -sS"
 
 # Querying the Github API to fetch all branches
-BRANCHES=$($CURL "${URL_RELEASES}" | jq -r "$JQ_BRANCHES")
+NEXT=$($CURL "${URL_RELEASES}" | jq -r "$JQ_NEXT")
 
-###
-# Building each branch
-###
-
-# keeping track whether an error occured
-ERROR=0
-
-# calling build.sh for each branch
-for BRANCH in $BRANCHES; do
+if [ -n "$NEXT" ]; then
   # shellcheck disable=SC2068
-  ./build.sh "${BRANCH}" $@ || ERROR=1
-done
-
-# returning whether an error occured
-exit $ERROR
+  ./build.sh "${NEXT}" $@
+else
+  echo "No branch matching 'develop-*' found"
+  echo "::set-output name=skipped::true"
+fi
diff --git a/build.sh b/build.sh
index 051cffb..7489ebb 100755
--- a/build.sh
+++ b/build.sh
@@ -49,7 +49,7 @@ if [ "${1}x" == "x" ] || [ "${1}" == "--help" ] || [ "${1}" == "-h" ]; then
   echo "  DOCKERFILE  The name of Dockerfile to use."
   echo "              Default: Dockerfile"
   echo "  DOCKER_FROM The base image to use."
-  echo "              Default: Whatever is defined as default in the Dockerfile."
+  echo "              Default: 'python:3.7-alpine'"
   echo "  DOCKER_TARGET A specific target to build."
   echo "              It's currently not possible to pass multiple targets."
   echo "              Default: main ldap"
@@ -153,6 +153,13 @@ if [ ! -f "${DOCKERFILE}" ]; then
   fi
 fi
 
+###
+# Determining the value for DOCKER_FROM
+###
+if [ -z "$DOCKER_FROM" ]; then
+  DOCKER_FROM="python:3.7-alpine"
+fi
+
 ###
 # Variables for labelling the docker image
 ###
@@ -167,9 +174,9 @@ PROJECT_VERSION="${PROJECT_VERSION-$(sed -e 's/^[[:space:]]*//' -e 's/[[:space:]
 
 # Get the Git information from the netbox directory
 if [ -d "${NETBOX_PATH}/.git" ]; then
-  NETBOX_GIT_REF=$(cd ${NETBOX_PATH}; git rev-parse HEAD)
-  NETBOX_GIT_BRANCH=$(cd ${NETBOX_PATH}; git rev-parse --abbrev-ref HEAD)
-  NETBOX_GIT_URL=$(cd ${NETBOX_PATH}; git remote get-url origin)
+  NETBOX_GIT_REF=$(cd "${NETBOX_PATH}"; git rev-parse HEAD)
+  NETBOX_GIT_BRANCH=$(cd "${NETBOX_PATH}"; git rev-parse --abbrev-ref HEAD)
+  NETBOX_GIT_URL=$(cd "${NETBOX_PATH}"; git remote get-url origin)
 fi
 
 ###
@@ -217,15 +224,18 @@ for DOCKER_TARGET in "${DOCKER_TARGETS[@]}"; do
   # composing the additional DOCKER_SHORT_TAG,
   # i.e. "v2.6.1" becomes "v2.6",
   # which is only relevant for version tags
+  # Also let "latest" follow the highest version
   ###
   if [[ "${TAG}" =~ ^v([0-9]+)\.([0-9]+)\.[0-9]+$ ]]; then
     MAJOR=${BASH_REMATCH[1]}
     MINOR=${BASH_REMATCH[2]}
 
     TARGET_DOCKER_SHORT_TAG="${DOCKER_SHORT_TAG-${DOCKER_REGISTRY}/${DOCKER_ORG}/${DOCKER_REPO}:v${MAJOR}.${MINOR}}"
+    TARGET_DOCKER_LATEST_TAG="${DOCKER_REGISTRY}/${DOCKER_ORG}/${DOCKER_REPO}:latest"
 
     if [ "${DOCKER_TARGET}" != "main" ]; then
       TARGET_DOCKER_SHORT_TAG="${TARGET_DOCKER_SHORT_TAG}-${DOCKER_TARGET}"
+      TARGET_DOCKER_LATEST_TAG="${TARGET_DOCKER_LATEST_TAG}-${DOCKER_TARGET}"
     fi
   fi
 
@@ -233,6 +243,48 @@ for DOCKER_TARGET in "${DOCKER_TARGETS[@]}"; do
   # Proceeding to buils stage, except if `--push-only` is passed
   ###
   if [ "${2}" != "--push-only" ] ; then
+    ###
+    # Checking if the build is necessary,
+    # meaning build only if one of those values changed:
+    # - Python base image digest (Label: PYTHON_BASE_DIGEST)
+    # - netbox git ref (Label: NETBOX_GIT_REF)
+    # - netbox-docker git ref (Label: org.label-schema.vcs-ref)
+    ###
+    # Load information from registry (only for docker.io)
+    SHOULD_BUILD="false"
+    BUILD_REASON=""
+    if [ -z "${GH_ACTION}" ]; then
+      # Asuming non Github builds should always proceed
+      SHOULD_BUILD="true"
+      BUILD_REASON="${BUILD_REASON} interactive"
+    elif [ "$DOCKER_REGISTRY" = "docker.io" ]; then
+      source ./build-functions/get-public-image-config.sh
+      IFS=':' read -ra DOCKER_FROM_SPLIT <<< "${DOCKER_FROM}"
+      if ! [[ ${DOCKER_FROM_SPLIT[0]} =~ .*/.* ]]; then
+        # Need to use "library/..." for images the have no two part name
+        DOCKER_FROM_SPLIT[0]="library/${DOCKER_FROM_SPLIT[0]}"
+      fi
+      PYTHON_LAST_LAYER=$(get_image_last_layer "${DOCKER_FROM_SPLIT[0]}" "${DOCKER_FROM_SPLIT[1]}")
+      mapfile -t IMAGES_LAYERS_OLD < <(get_image_layers "${DOCKER_ORG}"/"${DOCKER_REPO}" "${TAG}")
+      NETBOX_GIT_REF_OLD=$(get_image_label NETBOX_GIT_REF "${DOCKER_ORG}"/"${DOCKER_REPO}" "${TAG}")
+      GIT_REF_OLD=$(get_image_label org.label-schema.vcs-ref "${DOCKER_ORG}"/"${DOCKER_REPO}" "${TAG}")
+
+      if ! printf '%s\n' "${IMAGES_LAYERS_OLD[@]}" | grep -q -P "^${PYTHON_LAST_LAYER}\$"; then
+        SHOULD_BUILD="true"
+        BUILD_REASON="${BUILD_REASON} python"
+      fi
+      if [ "${NETBOX_GIT_REF}" != "${NETBOX_GIT_REF_OLD}" ]; then
+        SHOULD_BUILD="true"
+        BUILD_REASON="${BUILD_REASON} netbox"
+      fi
+      if [ "${GIT_REF}" != "${GIT_REF_OLD}" ]; then
+        SHOULD_BUILD="true"
+        BUILD_REASON="${BUILD_REASON} netbox-docker"
+      fi
+    else
+      SHOULD_BUILD="true"
+      BUILD_REASON="${BUILD_REASON} no-check"
+    fi
     ###
     # Composing all arguments for `docker build`
     ###
@@ -244,6 +296,7 @@ for DOCKER_TARGET in "${DOCKER_TARGETS[@]}"; do
     )
     if [ -n "${TARGET_DOCKER_SHORT_TAG}" ]; then
       DOCKER_BUILD_ARGS+=( -t "${TARGET_DOCKER_SHORT_TAG}" )
+      DOCKER_BUILD_ARGS+=( -t "${TARGET_DOCKER_LATEST_TAG}" )
     fi
 
     # --label
@@ -269,6 +322,10 @@ for DOCKER_TARGET in "${DOCKER_TARGETS[@]}"; do
         --label "NETBOX_GIT_URL=${NETBOX_GIT_URL}"
       )
     fi
+    if [ -n "${BUILD_REASON}" ]; then
+      BUILD_REASON=$(sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//' <<< "$BUILD_REASON")
+      DOCKER_BUILD_ARGS+=( --label "BUILD_REASON=${BUILD_REASON}" )
+    fi
 
     # --build-arg
     DOCKER_BUILD_ARGS+=(   --build-arg "NETBOX_PATH=${NETBOX_PATH}" )
@@ -287,25 +344,29 @@ for DOCKER_TARGET in "${DOCKER_TARGETS[@]}"; do
     ###
     # Building the docker image
     ###
-    echo "🐳 Building the Docker image '${TARGET_DOCKER_TAG}'."
-    $DRY docker build "${DOCKER_BUILD_ARGS[@]}" .
-    echo "✅ Finished building the Docker images '${TARGET_DOCKER_TAG}'"
+    if [ "${SHOULD_BUILD}" == "true" ]; then
+      echo "🐳 Building the Docker image '${TARGET_DOCKER_TAG}'."
+      echo "    Build reason set to: ${BUILD_REASON}"
+      $DRY docker build "${DOCKER_BUILD_ARGS[@]}" .
+      echo "✅ Finished building the Docker images '${TARGET_DOCKER_TAG}'"
+      echo "🔎 Inspecting labels on '${TARGET_DOCKER_TAG}'"
+      $DRY docker inspect "${TARGET_DOCKER_TAG}" --format "{{json .Config.Labels}}"
+    else
+      echo "Build skipped because sources didn't change"
+      echo "::set-output name=skipped::true"
+    fi
   fi
 
   ###
   # Pushing the docker images if either `--push` or `--push-only` are passed
   ###
   if [ "${2}" == "--push" ] || [ "${2}" == "--push-only" ] ; then
-    echo "⏫ Inspecting labels on '${TARGET_DOCKER_TAG}'"
-    $DRY docker inspect "${TARGET_DOCKER_TAG}" --format "{{json .Config.Labels}}"
-    echo "⏫ Pushing '${TARGET_DOCKER_TAG}'"
-    $DRY docker push "${TARGET_DOCKER_TAG}"
-    echo "✅ Finished pushing the Docker image '${TARGET_DOCKER_TAG}'."
+    source ./build-functions/docker-functions.sh
+    push_image_to_registry "${TARGET_DOCKER_TAG}"
 
     if [ -n "${TARGET_DOCKER_SHORT_TAG}" ]; then
-      echo "⏫ Pushing '${TARGET_DOCKER_SHORT_TAG}'"
-      $DRY docker push "${TARGET_DOCKER_SHORT_TAG}"
-      echo "✅ Finished pushing the Docker image '${TARGET_DOCKER_SHORT_TAG}'."
+      push_image_to_registry "${TARGET_DOCKER_SHORT_TAG}"
+      push_image_to_registry "${TARGET_DOCKER_LATEST_TAG}"
     fi
   fi
 done