diff --git a/.gitignore b/.gitignore
index 0c1b89ace..8e0db013f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -27,6 +27,8 @@ perl/Makefile.config
 # /scripts/
 /scripts/nix-profile.sh
 /scripts/nix-profile-daemon.sh
+/scripts/nix-profile.fish
+/scripts/nix-profile-daemon.fish
 
 # /src/libexpr/
 /src/libexpr/lexer-tab.cc
diff --git a/scripts/install-multi-user.sh b/scripts/install-multi-user.sh
index 9a990275c..a39339050 100644
--- a/scripts/install-multi-user.sh
+++ b/scripts/install-multi-user.sh
@@ -37,6 +37,19 @@ readonly PROFILE_TARGETS=("/etc/bashrc" "/etc/profile.d/nix.sh" "/etc/zshrc" "/e
 readonly PROFILE_BACKUP_SUFFIX=".backup-before-nix"
 readonly PROFILE_NIX_FILE="$NIX_ROOT/var/nix/profiles/default/etc/profile.d/nix-daemon.sh"
 
+# Fish has different syntax than zsh/bash, treat it separate
+readonly PROFILE_FISH_SUFFIX="conf.d/nix.fish"
+readonly PROFILE_FISH_PREFIXES=(
+    # each of these are common values of $__fish_sysconf_dir,
+    # under which Fish will look for a file named
+    # $PROFILE_FISH_SUFFIX.
+    "/etc/fish"              # standard
+    "/usr/local/etc/fish"    # their installer .pkg for macOS
+    "/opt/homebrew/etc/fish" # homebrew
+    "/opt/local/etc/fish"    # macports
+)
+readonly PROFILE_NIX_FILE_FISH="$NIX_ROOT/var/nix/profiles/default/etc/profile.d/nix-daemon.fish"
+
 readonly NIX_INSTALLED_NIX="@nix@"
 readonly NIX_INSTALLED_CACERT="@cacert@"
 #readonly NIX_INSTALLED_NIX="/nix/store/j8dbv5w6jl34caywh2ygdy88knx1mdf7-nix-2.3.6"
@@ -828,6 +841,19 @@ fi
 EOF
 }
 
+# Fish has differing syntax
+fish_source_lines() {
+    cat <<EOF
+
+# Nix
+if test -e '$PROFILE_NIX_FILE_FISH'
+  . '$PROFILE_NIX_FILE_FISH'
+end
+# End Nix
+
+EOF
+}
+
 configure_shell_profile() {
     task "Setting up shell profiles: ${PROFILE_TARGETS[*]}"
     for profile_target in "${PROFILE_TARGETS[@]}"; do
@@ -849,6 +875,27 @@ configure_shell_profile() {
                         tee -a "$profile_target"
         fi
     done
+
+    task "Setting up shell profiles for Fish with with ${PROFILE_FISH_SUFFIX} inside ${PROFILE_FISH_PREFIXES[*]}"
+    for fish_prefix in "${PROFILE_FISH_PREFIXES[@]}"; do
+        if [ ! -d "$fish_prefix" ]; then
+            # this specific prefix (ie: /etc/fish) is very likely to exist
+            # if Fish is installed with this sysconfdir.
+            continue
+        fi
+
+        profile_target="${fish_prefix}/${PROFILE_FISH_SUFFIX}"
+        conf_dir=$(dirname "$profile_target")
+        if [ ! -d "$conf_dir" ]; then
+            _sudo "create $conf_dir for our Fish hook" \
+                mkdir "$conf_dir"
+        fi
+
+        fish_source_lines \
+            | _sudo "write nix-daemon settings to $profile_target" \
+                    tee "$profile_target"
+    done
+
     # TODO: should we suggest '. $PROFILE_NIX_FILE'? It would get them on
     # their way less disruptively, but a counter-argument is that they won't
     # immediately notice if something didn't get set up right?
diff --git a/scripts/install-nix-from-closure.sh b/scripts/install-nix-from-closure.sh
index cd3cf6670..d4eed2efe 100644
--- a/scripts/install-nix-from-closure.sh
+++ b/scripts/install-nix-from-closure.sh
@@ -209,31 +209,50 @@ if [ -z "$NIX_INSTALLER_NO_CHANNEL_ADD" ]; then
 fi
 
 added=
-p=$HOME/.nix-profile/etc/profile.d/nix.sh
+p=
+p_sh=$HOME/.nix-profile/etc/profile.d/nix.sh
+p_fish=$HOME/.nix-profile/etc/profile.d/nix.fish
 if [ -z "$NIX_INSTALLER_NO_MODIFY_PROFILE" ]; then
     # Make the shell source nix.sh during login.
     for i in .bash_profile .bash_login .profile; do
         fn="$HOME/$i"
         if [ -w "$fn" ]; then
-            if ! grep -q "$p" "$fn"; then
+            if ! grep -q "$p_sh" "$fn"; then
                 echo "modifying $fn..." >&2
-                printf '\nif [ -e %s ]; then . %s; fi # added by Nix installer\n' "$p" "$p" >> "$fn"
+                printf '\nif [ -e %s ]; then . %s; fi # added by Nix installer\n' "$p_sh" "$p_sh" >> "$fn"
             fi
             added=1
+            p=${p_sh}
             break
         fi
     done
     for i in .zshenv .zshrc; do
         fn="$HOME/$i"
         if [ -w "$fn" ]; then
-            if ! grep -q "$p" "$fn"; then
+            if ! grep -q "$p_sh" "$fn"; then
                 echo "modifying $fn..." >&2
-                printf '\nif [ -e %s ]; then . %s; fi # added by Nix installer\n' "$p" "$p" >> "$fn"
+                printf '\nif [ -e %s ]; then . %s; fi # added by Nix installer\n' "$p_sh" "$p_sh" >> "$fn"
             fi
             added=1
+            p=${p_sh}
             break
         fi
     done
+
+    if [ -d "$HOME/.config/fish" ]; then
+        fishdir=$HOME/.config/fish/conf.d
+        if [ ! -d "$fishdir" ]; then
+            mkdir -p "$fishdir"
+        fi
+
+        fn="$fishdir/nix.fish"
+        echo "placing $fn..." >&2
+        printf '\nif test -e %s; . %s; end # added by Nix installer\n' "$p_fish" "$p_fish" > "$fn"
+        added=1
+        p=${p_fish}
+    fi
+else
+    p=${p_sh}
 fi
 
 if [ -z "$added" ]; then
diff --git a/scripts/local.mk b/scripts/local.mk
index b8477178e..46255e432 100644
--- a/scripts/local.mk
+++ b/scripts/local.mk
@@ -6,6 +6,8 @@ noinst-scripts += $(nix_noinst_scripts)
 profiledir = $(sysconfdir)/profile.d
 
 $(eval $(call install-file-as, $(d)/nix-profile.sh, $(profiledir)/nix.sh, 0644))
+$(eval $(call install-file-as, $(d)/nix-profile.fish, $(profiledir)/nix.fish, 0644))
 $(eval $(call install-file-as, $(d)/nix-profile-daemon.sh, $(profiledir)/nix-daemon.sh, 0644))
+$(eval $(call install-file-as, $(d)/nix-profile-daemon.fish, $(profiledir)/nix-daemon.fish, 0644))
 
 clean-files += $(nix_noinst_scripts)
diff --git a/scripts/nix-profile-daemon.fish.in b/scripts/nix-profile-daemon.fish.in
new file mode 100644
index 000000000..56d851a9c
--- /dev/null
+++ b/scripts/nix-profile-daemon.fish.in
@@ -0,0 +1,35 @@
+# Only execute this file once per shell.
+if test -n "$__ETC_PROFILE_NIX_SOURCED"
+  return
+end
+
+set __ETC_PROFILE_NIX_SOURCED 1
+
+set --export NIX_PROFILES "@localstatedir@/nix/profiles/default $HOME/.nix-profile"
+
+# Set $NIX_SSL_CERT_FILE so that Nixpkgs applications like curl work.
+if test -n "$NIX_SSH_CERT_FILE"
+  : # Allow users to override the NIX_SSL_CERT_FILE
+else if test -e /etc/ssl/certs/ca-certificates.crt # NixOS, Ubuntu, Debian, Gentoo, Arch
+  set --export NIX_SSL_CERT_FILE /etc/ssl/certs/ca-certificates.crt
+else if test -e /etc/ssl/ca-bundle.pem # openSUSE Tumbleweed
+  set --export NIX_SSL_CERT_FILE /etc/ssl/ca-bundle.pem
+else if test -e /etc/ssl/certs/ca-bundle.crt # Old NixOS
+  set --export NIX_SSL_CERT_FILE /etc/ssl/certs/ca-bundle.crt
+else if test -e /etc/pki/tls/certs/ca-bundle.crt # Fedora, CentOS
+  set --export NIX_SSL_CERT_FILE /etc/pki/tls/certs/ca-bundle.crt
+else if test -e "$NIX_LINK/etc/ssl/certs/ca-bundle.crt" # fall back to cacert in Nix profile
+  set --export NIX_SSL_CERT_FILE "$NIX_LINK/etc/ssl/certs/ca-bundle.crt"
+else if test -e "$NIX_LINK/etc/ca-bundle.crt" # old cacert in Nix profile
+  set --export NIX_SSL_CERT_FILE "$NIX_LINK/etc/ca-bundle.crt"
+else
+  # Fall back to what is in the nix profiles, favouring whatever is defined last.
+  for i in $NIX_PROFILES
+    if test -e "$i/etc/ssl/certs/ca-bundle.crt"
+      set --export NIX_SSL_CERT_FILE "$i/etc/ssl/certs/ca-bundle.crt"
+    end
+  end
+end
+
+fish_add_path --prepend --global "@localstatedir@/nix/profiles/default/bin"
+fish_add_path --prepend --global "$HOME/.nix-profile/bin"
diff --git a/scripts/nix-profile.fish.in b/scripts/nix-profile.fish.in
new file mode 100644
index 000000000..59d247771
--- /dev/null
+++ b/scripts/nix-profile.fish.in
@@ -0,0 +1,35 @@
+if test -n "$HOME" && test -n "$USER"
+
+    # Set up the per-user profile.
+
+    set NIX_LINK $HOME/.nix-profile
+
+    # Set up environment.
+    # This part should be kept in sync with nixpkgs:nixos/modules/programs/environment.nix
+    set --export NIX_PROFILES "@localstatedir@/nix/profiles/default $HOME/.nix-profile"
+
+    # Set $NIX_SSL_CERT_FILE so that Nixpkgs applications like curl work.
+    if test -n "$NIX_SSH_CERT_FILE"
+        : # Allow users to override the NIX_SSL_CERT_FILE
+    else if test -e /etc/ssl/certs/ca-certificates.crt # NixOS, Ubuntu, Debian, Gentoo, Arch
+        set --export NIX_SSL_CERT_FILE /etc/ssl/certs/ca-certificates.crt
+    else if test -e /etc/ssl/ca-bundle.pem # openSUSE Tumbleweed
+        set --export NIX_SSL_CERT_FILE /etc/ssl/ca-bundle.pem
+    else if test -e /etc/ssl/certs/ca-bundle.crt # Old NixOS
+        set --export NIX_SSL_CERT_FILE /etc/ssl/certs/ca-bundle.crt
+    else if test -e /etc/pki/tls/certs/ca-bundle.crt # Fedora, CentOS
+        set --export NIX_SSL_CERT_FILE /etc/pki/tls/certs/ca-bundle.crt
+    else if test -e "$NIX_LINK/etc/ssl/certs/ca-bundle.crt" # fall back to cacert in Nix profile
+        set --export NIX_SSL_CERT_FILE "$NIX_LINK/etc/ssl/certs/ca-bundle.crt"
+    else if test -e "$NIX_LINK/etc/ca-bundle.crt" # old cacert in Nix profile
+        set --export NIX_SSL_CERT_FILE "$NIX_LINK/etc/ca-bundle.crt"
+    end
+
+    # Only use MANPATH if it is already set. In general `man` will just simply
+    # pick up `.nix-profile/share/man` because is it close to `.nix-profile/bin`
+    # which is in the $PATH. For more info, run `manpath -d`.
+    set --export --prepend --path MANPATH "$NIX_LINK/share/man"
+
+    fish_add_path --prepend --global "$NIX_LINK/bin"
+    set --erase NIX_LINK
+end
diff --git a/scripts/nix-profile.sh.in b/scripts/nix-profile.sh.in
index 45cbcbe74..5636085d4 100644
--- a/scripts/nix-profile.sh.in
+++ b/scripts/nix-profile.sh.in
@@ -1,7 +1,6 @@
 if [ -n "$HOME" ] && [ -n "$USER" ]; then
 
     # Set up the per-user profile.
-    # This part should be kept in sync with nixpkgs:nixos/modules/programs/shell.nix
 
     NIX_LINK=$HOME/.nix-profile