diff --git a/install.sh b/install.sh
index 16382b3..3bcb6f0 100755
--- a/install.sh
+++ b/install.sh
@@ -100,20 +100,32 @@ nvm_download() {
 install_nvm_from_git() {
   local INSTALL_DIR
   INSTALL_DIR="$(nvm_install_dir)"
+  local NVM_VERSION
+  NVM_VERSION="${NVM_INSTALL_VERSION:-$(nvm_latest_version)}"
+  if [ -n "${NVM_INSTALL_VERSION:-}" ]; then
+    # Check if version is an existing ref
+    if command git ls-remote "$(nvm_source "git")" "$NVM_VERSION" | nvm_grep -q "$NVM_VERSION" ; then
+      :
+    # Check if version is an existing changeset
+    elif ! nvm_download -o /dev/null "$(nvm_source "script-nvm-exec")"; then
+      echo >&2 "Failed to find '$NVM_VERSION' version."
+      exit 1
+    fi
+  fi
 
+  local fetch_error
   if [ -d "$INSTALL_DIR/.git" ]; then
+    # Updating repo
     echo "=> nvm is already installed in $INSTALL_DIR, trying to update using git"
     command printf '\r=> '
-    command git --git-dir="$INSTALL_DIR"/.git --work-tree="$INSTALL_DIR" fetch origin tag "$(nvm_latest_version)" --depth=1 2> /dev/null || {
-      echo >&2 "Failed to update nvm, run 'git fetch' in $INSTALL_DIR yourself."
-      exit 1
-    }
+    fetch_error="Failed to update nvm with $NVM_VERSION, run 'git fetch' in $INSTALL_DIR yourself."
   else
-    # Cloning to $INSTALL_DIR
+    fetch_error="Failed to fetch origin with $NVM_VERSION. Please report this!"
     echo "=> Downloading nvm from git to '$INSTALL_DIR'"
     command printf '\r=> '
     mkdir -p "${INSTALL_DIR}"
     if [ "$(ls -A "${INSTALL_DIR}")" ]; then
+      # Initializing repo
       command git init "${INSTALL_DIR}" || {
         echo >&2 'Failed to initialize nvm repo. Please report this!'
         exit 2
@@ -123,18 +135,26 @@ install_nvm_from_git() {
         echo >&2 'Failed to add remote "origin" (or set the URL). Please report this!'
         exit 2
       }
-      command git --git-dir="${INSTALL_DIR}/.git" fetch origin tag "$(nvm_latest_version)" --depth=1 || {
-        echo >&2 'Failed to fetch origin with tags. Please report this!'
-        exit 2
-      }
     else
-      command git -c advice.detachedHead=false clone "$(nvm_source)" -b "$(nvm_latest_version)" --depth=1 "${INSTALL_DIR}" || {
+      # Cloning repo
+      command git clone "$(nvm_source)" --depth=1 "${INSTALL_DIR}" || {
         echo >&2 'Failed to clone nvm repo. Please report this!'
         exit 2
       }
     fi
   fi
-  command git -c advice.detachedHead=false --git-dir="$INSTALL_DIR"/.git --work-tree="$INSTALL_DIR" checkout -f --quiet "$(nvm_latest_version)"
+  # Try to fetch tag
+  if command git --git-dir="$INSTALL_DIR"/.git --work-tree="$INSTALL_DIR" fetch origin tag "$NVM_VERSION" --depth=1 2>/dev/null; then
+    :
+  # Fetch given version
+  elif ! command git --git-dir="$INSTALL_DIR"/.git --work-tree="$INSTALL_DIR" fetch origin "$NVM_VERSION" --depth=1; then
+    echo >&2 "$fetch_error"
+    exit 1
+  fi
+  command git -c advice.detachedHead=false --git-dir="$INSTALL_DIR"/.git --work-tree="$INSTALL_DIR" checkout -f --quiet FETCH_HEAD || {
+    echo >&2 "Failed to checkout the given version $NVM_VERSION. Please report this!"
+    exit 2
+  }
   if [ -n "$(command git --git-dir="$INSTALL_DIR"/.git --work-tree="$INSTALL_DIR" show-ref refs/heads/master)" ]; then
     if command git --git-dir="$INSTALL_DIR"/.git --work-tree="$INSTALL_DIR" branch --quiet 2>/dev/null; then
       command git --git-dir="$INSTALL_DIR"/.git --work-tree="$INSTALL_DIR" branch --quiet -D master >/dev/null 2>&1
diff --git a/test/install_script/install_nvm_from_git b/test/install_script/install_nvm_from_git
new file mode 100755
index 0000000..161bbcb
--- /dev/null
+++ b/test/install_script/install_nvm_from_git
@@ -0,0 +1,121 @@
+#!/bin/sh
+
+SAVE_NVM_DIR="$NVM_DIR"
+SAVE_NVM_INSTALL_VERSION="$NVM_INSTALL_VERSION"
+
+cleanup () {
+  NVM_DIR="$SAVE_NVM_DIR"
+  NVM_INSTALL_VERSION="$SAVE_NVM_INSTALL_VERSION"
+  unset SAVE_NVM_DIR SAVE_NVM_INSTALL_VERSION
+  unset -f die cleanup test_step get_head_ref get_head_changeset get_fetch_head_changeset \
+    step_to_previous_changeset test_install_data test_install
+}
+
+die () { echo -e "$@" ; cleanup ;  exit 1; }
+
+NVM_ENV=testing \. ../../install.sh
+
+set -ex
+
+# nvm_do_install is available
+type install_nvm_from_git > /dev/null 2>&1 || die 'install_nvm_from_git is not available'
+
+test_step() {
+  echo -e "\e[33m$*\e[0m"
+}
+
+get_head_ref(){
+  git --git-dir "$NVM_DIR"/.git --no-pager log --pretty=format:'%d' -1
+}
+
+get_head_changeset() {
+  git --git-dir "$NVM_DIR"/.git rev-parse --verify HEAD
+}
+
+get_fetch_head_changeset() {
+  git --git-dir "$NVM_DIR"/.git rev-parse --verify FETCH_HEAD
+}
+
+step_to_previous_changeset() {
+  git --git-dir "$NVM_DIR"/.git fetch origin +"$(get_head_changeset)" --depth=2
+  git --git-dir "$NVM_DIR"/.git reset --hard HEAD~1
+}
+
+# args:
+#   - 1: current ref
+#   - 2: current changeset
+#   - 3: error message
+#   - 4: ref to check ("" if none)
+#   - 5: changeset to check ("" if none)
+#   - 6: ref to avoid ("" if none)
+test_install_data() {
+  local current_ref="$1"
+  local current_changeset="$2"
+  local message="$3"
+  local ref="$4"
+  local changeset="$5"
+  local avoid_ref="$6"
+  if [ -n "$ref" ]; then
+    echo "$current_ref" | grep -q "$ref" || die "install_nvm_from_git $message did not clone with ref $ref"
+  fi
+  if [ -n "$avoid_ref" ]; then
+    echo "$current_ref" | grep -q "$avoid_ref" && die "install_nvm_from_git $message did clone with unwanted ref $avoid_ref"
+  fi
+  if [ -n "$changeset" ]; then
+    echo "$current_changeset" | grep -q "$changeset" || die "install_nvm_from_git $message did not clone with changeset $changeset"
+  fi
+}
+
+# args:
+#   - 1: version to install ("" for latest, tag, ref or changeset)
+#   - 2: error message
+#   - 3: ref to check ("" if none)
+#   - 4: changeset to check ("" if none)
+#   - 5: ref to avoid ("" if none)
+test_install() {
+  NVM_INSTALL_VERSION="$1"
+  local message="$2"
+  local ref="$3"
+  local changeset="$4"
+  local avoid_ref="$5"
+
+  NVM_DIR=$(mktemp -d) || die 'Unable to create temporary directory'
+  NVM_DIR="$NVM_DIR/clone"
+
+  # Ensure it clones the repository for non existing directory
+  test_step "Clones repo $message"
+  install_nvm_from_git
+  test_install_data "$(get_head_ref)" "$(get_head_changeset)" "$message" "$ref" "$changeset" "$avoid_ref"
+  rm -rf "$NVM_DIR"
+
+  # Ensure it initializes the repository for an empty existing repository
+  mkdir -p "$NVM_DIR" || die 'Unable to create directory'
+  test_step "Initialize repo $message"
+  install_nvm_from_git
+  test_install_data "$(get_head_ref)" "$(get_head_changeset)" "$message" "$ref" "$changeset" "$avoid_ref"
+  rm -rf "$NVM_DIR"
+
+  # Ensure it updates the repository for an existing git repository
+  git clone "$(nvm_source "git")" -b "v0.36.0" --depth=2 "$NVM_DIR" || die 'Unable to clone repository'
+  step_to_previous_changeset
+  test_step "Updates repo $message"
+  install_nvm_from_git
+  test_install_data "$(get_head_ref)" "$(get_head_changeset)" "$message" "$ref" "$changeset" "$avoid_ref"
+  rm -rf "$NVM_DIR"
+}
+
+# Handle latest version
+test_install "" "latest version" "$(nvm_latest_version)"
+
+# Handle given changeset
+changeset="3abb98124e8d30c9652976c9d34a7380036083b5"
+test_install "$changeset" "with changeset $changeset" "" "$changeset" "$(nvm_latest_version)"
+
+# Handle given tag
+test_install "v0.37.0" "version v0.37.0" "v0.37.0" "4054bd70cedb9998015c2d8cc468c818c7d2f57d" "$(nvm_latest_version)"
+
+# Handle given ref
+test_install "refs/pull/2397/head" "with refs/pull/2397/head" "" "9849bf494d50e74aa810451fb1f83208b0092dd6" "$(nvm_latest_version)"
+test_install "master" "master" "" "" "$(nvm_latest_version)"
+
+cleanup