treewide: use boolToString function

40 files changed, 111 insertions, 118 deletions

diff --git a/lib/trivial.nix b/lib/trivial.nix
index acbd687dd98..62906339e60 100644
--- a/lib/trivial.nix
+++ b/lib/trivial.nix
@@ -30,6 +30,11 @@ rec {
   /* boolean “and” */
   and = x: y: x && y;
 
+  /* Convert a boolean to a string.
+     Note that toString on a bool returns "1" and "".
+  */
+  boolToString = b: if b then "true" else "false";
+
   /* Merge two attribute sets shallowly, right side trumps left
 
      Example:
diff --git a/nixos/modules/config/fonts/fontconfig-penultimate.nix b/nixos/modules/config/fonts/fontconfig-penultimate.nix
index 83d6532774e..3e163b8ec51 100644
--- a/nixos/modules/config/fonts/fontconfig-penultimate.nix
+++ b/nixos/modules/config/fonts/fontconfig-penultimate.nix
@@ -5,7 +5,7 @@ with lib;
 let
   cfg = config.fonts.fontconfig;
 
-  fcBool = x: "<bool>" + (if x then "true" else "false") + "</bool>";
+  fcBool = x: "<bool>" + (boolToString x) + "</bool>";
 
   # back-supported fontconfig version and package
   # version is used for font cache generation
diff --git a/nixos/modules/config/fonts/fontconfig.nix b/nixos/modules/config/fonts/fontconfig.nix
index d44b583447a..12f5ca2e799 100644
--- a/nixos/modules/config/fonts/fontconfig.nix
+++ b/nixos/modules/config/fonts/fontconfig.nix
@@ -20,7 +20,7 @@ with lib;
 
 let cfg = config.fonts.fontconfig;
 
-    fcBool = x: "<bool>" + (if x then "true" else "false") + "</bool>";
+    fcBool = x: "<bool>" + (boolToString x) + "</bool>";
 
     # back-supported fontconfig version and package
     # version is used for font cache generation
diff --git a/nixos/modules/services/cluster/kubernetes.nix b/nixos/modules/services/cluster/kubernetes.nix
index 9ccc7295019..bf7b44c698c 100644
--- a/nixos/modules/services/cluster/kubernetes.nix
+++ b/nixos/modules/services/cluster/kubernetes.nix
@@ -612,8 +612,8 @@ in {
             --require-kubeconfig \
             --address=${cfg.kubelet.address} \
             --port=${toString cfg.kubelet.port} \
-            --register-node=${if cfg.kubelet.registerNode then "true" else "false"} \
-            --register-schedulable=${if cfg.kubelet.registerSchedulable then "true" else "false"} \
+            --register-node=${boolToString cfg.kubelet.registerNode} \
+            --register-schedulable=${boolToString cfg.kubelet.registerSchedulable} \
             ${optionalString (cfg.kubelet.tlsCertFile != null)
               "--tls-cert-file=${cfg.kubelet.tlsCertFile}"} \
             ${optionalString (cfg.kubelet.tlsKeyFile != null)
@@ -621,7 +621,7 @@ in {
             --healthz-bind-address=${cfg.kubelet.healthz.bind} \
             --healthz-port=${toString cfg.kubelet.healthz.port} \
             --hostname-override=${cfg.kubelet.hostname} \
-            --allow-privileged=${if cfg.kubelet.allowPrivileged then "true" else "false"} \
+            --allow-privileged=${boolToString cfg.kubelet.allowPrivileged} \
             --root-dir=${cfg.dataDir} \
             --cadvisor_port=${toString cfg.kubelet.cadvisorPort} \
             ${optionalString (cfg.kubelet.clusterDns != "")
@@ -670,14 +670,14 @@ in {
             --bind-address=0.0.0.0 \
             ${optionalString (cfg.apiserver.advertiseAddress != null)
               "--advertise-address=${cfg.apiserver.advertiseAddress}"} \
-            --allow-privileged=${if cfg.apiserver.allowPrivileged then "true" else "false"} \
+            --allow-privileged=${boolToString cfg.apiserver.allowPrivileged}\
             ${optionalString (cfg.apiserver.tlsCertFile != null)
               "--tls-cert-file=${cfg.apiserver.tlsCertFile}"} \
             ${optionalString (cfg.apiserver.tlsKeyFile != null)
               "--tls-private-key-file=${cfg.apiserver.tlsKeyFile}"} \
             ${optionalString (cfg.apiserver.tokenAuth != null)
               "--token-auth-file=${cfg.apiserver.tokenAuth}"} \
-            --kubelet-https=${if cfg.apiserver.kubeletHttps then "true" else "false"} \
+            --kubelet-https=${boolToString cfg.apiserver.kubeletHttps} \
             ${optionalString (cfg.apiserver.kubeletClientCaFile != null)
               "--kubelet-certificate-authority=${cfg.apiserver.kubeletClientCaFile}"} \
             ${optionalString (cfg.apiserver.kubeletClientCertFile != null)
@@ -719,7 +719,7 @@ in {
           ExecStart = ''${cfg.package}/bin/kube-scheduler \
             --address=${cfg.scheduler.address} \
             --port=${toString cfg.scheduler.port} \
-            --leader-elect=${if cfg.scheduler.leaderElect then "true" else "false"} \
+            --leader-elect=${boolToString cfg.scheduler.leaderElect} \
             --kubeconfig=${kubeconfig} \
             ${optionalString cfg.verbose "--v=6"} \
             ${optionalString cfg.verbose "--log-flush-frequency=1s"} \
@@ -744,7 +744,7 @@ in {
             --address=${cfg.controllerManager.address} \
             --port=${toString cfg.controllerManager.port} \
             --kubeconfig=${kubeconfig} \
-            --leader-elect=${if cfg.controllerManager.leaderElect then "true" else "false"} \
+            --leader-elect=${boolToString cfg.controllerManager.leaderElect} \
             ${if (cfg.controllerManager.serviceAccountKeyFile!=null)
               then "--service-account-private-key-file=${cfg.controllerManager.serviceAccountKeyFile}"
               else "--service-account-private-key-file=/var/run/kubernetes/apiserver.key"} \
diff --git a/nixos/modules/services/continuous-integration/hydra/default.nix b/nixos/modules/services/continuous-integration/hydra/default.nix
index fa550f68b33..57f592a2e55 100644
--- a/nixos/modules/services/continuous-integration/hydra/default.nix
+++ b/nixos/modules/services/continuous-integration/hydra/default.nix
@@ -328,7 +328,7 @@ in
           IN_SYSTEMD = "1"; # to get log severity levels
         };
         serviceConfig =
-          { ExecStart = "@${cfg.package}/bin/hydra-queue-runner hydra-queue-runner -v --option build-use-substitutes ${if cfg.useSubstitutes then "true" else "false"}";
+          { ExecStart = "@${cfg.package}/bin/hydra-queue-runner hydra-queue-runner -v --option build-use-substitutes ${boolToString cfg.useSubstitutes}";
             ExecStopPost = "${cfg.package}/bin/hydra-queue-runner --unlock";
             User = "hydra-queue-runner";
             Restart = "always";
diff --git a/nixos/modules/services/databases/cassandra.nix b/nixos/modules/services/databases/cassandra.nix
index 5df4ae57f80..1e5cd8f5413 100644
--- a/nixos/modules/services/databases/cassandra.nix
+++ b/nixos/modules/services/databases/cassandra.nix
@@ -21,8 +21,8 @@ let
   cassandraConf = ''
     cluster_name: ${cfg.clusterName}
     num_tokens: 256
-    auto_bootstrap: ${if cfg.autoBootstrap then "true" else "false"}
-    hinted_handoff_enabled: ${if cfg.hintedHandOff then "true" else "false"}
+    auto_bootstrap: ${boolToString cfg.autoBootstrap}
+    hinted_handoff_enabled: ${boolToString cfg.hintedHandOff}
     hinted_handoff_throttle_in_kb: ${builtins.toString cfg.hintedHandOffThrottle}
     max_hints_delivery_threads: 2
     max_hint_window_in_ms: 10800000 # 3 hours
@@ -62,7 +62,7 @@ let
     rpc_keepalive: true
     rpc_server_type: sync
     thrift_framed_transport_size_in_mb: 15
-    incremental_backups: ${if cfg.incrementalBackups then "true" else "false"}
+    incremental_backups: ${boolToString cfg.incrementalBackups}
     snapshot_before_compaction: false
     auto_snapshot: true
     column_index_size_in_kb: 64
@@ -89,7 +89,7 @@ let
       truststore: ${cfg.trustStorePath}
       truststore_password: ${cfg.trustStorePassword}
     client_encryption_options:
-      enabled: ${if cfg.clientEncryption then "true" else "false"}
+      enabled: ${boolToString cfg.clientEncryption}
       keystore: ${cfg.keyStorePath}
       keystore_password: ${cfg.keyStorePassword}
     internode_compression: all
diff --git a/nixos/modules/services/databases/mongodb.nix b/nixos/modules/services/databases/mongodb.nix
index 38e46a0c6ef..c56564f57f3 100644
--- a/nixos/modules/services/databases/mongodb.nix
+++ b/nixos/modules/services/databases/mongodb.nix
@@ -4,8 +4,6 @@ with lib;
 
 let
 
-  b2s = x: if x then "true" else "false";
-
   cfg = config.services.mongodb;
 
   mongodb = cfg.package;
diff --git a/nixos/modules/services/logging/graylog.nix b/nixos/modules/services/logging/graylog.nix
index 95283096662..9f0fb11f025 100644
--- a/nixos/modules/services/logging/graylog.nix
+++ b/nixos/modules/services/logging/graylog.nix
@@ -4,16 +4,15 @@ with lib;
 
 let
   cfg = config.services.graylog;
-  configBool = b: if b then "true" else "false";
 
   confFile = pkgs.writeText "graylog.conf" ''
-    is_master = ${configBool cfg.isMaster}
+    is_master = ${boolToString cfg.isMaster}
     node_id_file = ${cfg.nodeIdFile}
     password_secret = ${cfg.passwordSecret}
     root_username = ${cfg.rootUsername}
     root_password_sha2 = ${cfg.rootPasswordSha2}
     elasticsearch_cluster_name = ${cfg.elasticsearchClusterName}
-    elasticsearch_discovery_zen_ping_multicast_enabled = ${configBool cfg.elasticsearchDiscoveryZenPingMulticastEnabled}
+    elasticsearch_discovery_zen_ping_multicast_enabled = ${boolToString cfg.elasticsearchDiscoveryZenPingMulticastEnabled}
     elasticsearch_discovery_zen_ping_unicast_hosts = ${cfg.elasticsearchDiscoveryZenPingUnicastHosts}
     message_journal_dir = ${cfg.messageJournalDir}
     mongodb_uri = ${cfg.mongodbUri}
diff --git a/nixos/modules/services/misc/cgminer.nix b/nixos/modules/services/misc/cgminer.nix
index 5f97cc03414..d5071d8ff76 100644
--- a/nixos/modules/services/misc/cgminer.nix
+++ b/nixos/modules/services/misc/cgminer.nix
@@ -6,7 +6,7 @@ let
   cfg = config.services.cgminer;
 
   convType = with builtins;
-    v: if isBool v then (if v then "true" else "false") else toString v;
+    v: if isBool v then boolToString v else toString v;
   mergedHwConfig =
     mapAttrsToList (n: v: ''"${n}": "${(concatStringsSep "," (map convType v))}"'')
       (foldAttrs (n: a: [n] ++ a) [] cfg.hardware);
diff --git a/nixos/modules/services/misc/confd.nix b/nixos/modules/services/misc/confd.nix
index fe13013286b..8e9bec15dd4 100755
--- a/nixos/modules/services/misc/confd.nix
+++ b/nixos/modules/services/misc/confd.nix
@@ -12,7 +12,7 @@ let
     nodes = [ ${concatMapStringsSep "," (s: ''"${s}"'') cfg.nodes}, ]
     prefix = "${cfg.prefix}"
     log-level = "${cfg.logLevel}"
-    watch = ${if cfg.watch then "true" else "false"}
+    watch = ${boolToString cfg.watch}
   '';
 
 in {
diff --git a/nixos/modules/services/misc/matrix-synapse.nix b/nixos/modules/services/misc/matrix-synapse.nix
index 4a1bea50c14..ae9826968b1 100644
--- a/nixos/modules/services/misc/matrix-synapse.nix
+++ b/nixos/modules/services/misc/matrix-synapse.nix
@@ -5,9 +5,8 @@ with lib;
 let
   cfg = config.services.matrix-synapse;
   logConfigFile = pkgs.writeText "log_config.yaml" cfg.logConfig;
-  mkResource = r: ''{names: ${builtins.toJSON r.names}, compress: ${fromBool r.compress}}'';
-  mkListener = l: ''{port: ${toString l.port}, bind_address: "${l.bind_address}", type: ${l.type}, tls: ${fromBool l.tls}, x_forwarded: ${fromBool l.x_forwarded}, resources: [${concatStringsSep "," (map mkResource l.resources)}]}'';
-  fromBool = x: if x then "true" else "false";
+  mkResource = r: ''{names: ${builtins.toJSON r.names}, compress: ${boolToString r.compress}}'';
+  mkListener = l: ''{port: ${toString l.port}, bind_address: "${l.bind_address}", type: ${l.type}, tls: ${boolToString l.tls}, x_forwarded: ${boolToString l.x_forwarded}, resources: [${concatStringsSep "," (map mkResource l.resources)}]}'';
   configFile = pkgs.writeText "homeserver.yaml" ''
 ${optionalString (cfg.tls_certificate_path != null) ''
 tls_certificate_path: "${cfg.tls_certificate_path}"
@@ -18,7 +17,7 @@ tls_private_key_path: "${cfg.tls_private_key_path}"
 ${optionalString (cfg.tls_dh_params_path != null) ''
 tls_dh_params_path: "${cfg.tls_dh_params_path}"
 ''}
-no_tls: ${fromBool cfg.no_tls}
+no_tls: ${boolToString cfg.no_tls}
 ${optionalString (cfg.bind_port != null) ''
 bind_port: ${toString cfg.bind_port}
 ''}
@@ -30,7 +29,7 @@ bind_host: "${cfg.bind_host}"
 ''}
 server_name: "${cfg.server_name}"
 pid_file: "/var/run/matrix-synapse.pid"
-web_client: ${fromBool cfg.web_client}
+web_client: ${boolToString cfg.web_client}
 ${optionalString (cfg.public_baseurl != null) ''
 public_baseurl: "${cfg.public_baseurl}"
 ''}
@@ -58,8 +57,8 @@ media_store_path: "/var/lib/matrix-synapse/media"
 uploads_path: "/var/lib/matrix-synapse/uploads"
 max_upload_size: "${cfg.max_upload_size}"
 max_image_pixels: "${cfg.max_image_pixels}"
-dynamic_thumbnails: ${fromBool cfg.dynamic_thumbnails}
-url_preview_enabled: ${fromBool cfg.url_preview_enabled}
+dynamic_thumbnails: ${boolToString cfg.dynamic_thumbnails}
+url_preview_enabled: ${boolToString cfg.url_preview_enabled}
 ${optionalString (cfg.url_preview_enabled == true) ''
 url_preview_ip_range_blacklist: ${builtins.toJSON cfg.url_preview_ip_range_blacklist}
 url_preview_ip_range_whitelist: ${builtins.toJSON cfg.url_preview_ip_range_whitelist}
@@ -67,10 +66,10 @@ url_preview_url_blacklist: ${builtins.toJSON cfg.url_preview_url_blacklist}
 ''}
 recaptcha_private_key: "${cfg.recaptcha_private_key}"
 recaptcha_public_key: "${cfg.recaptcha_public_key}"
-enable_registration_captcha: ${fromBool cfg.enable_registration_captcha}
+enable_registration_captcha: ${boolToString cfg.enable_registration_captcha}
 turn_uris: ${builtins.toJSON cfg.turn_uris}
 turn_shared_secret: "${cfg.turn_shared_secret}"
-enable_registration: ${fromBool cfg.enable_registration}
+enable_registration: ${boolToString cfg.enable_registration}
 ${optionalString (cfg.registration_shared_secret != null) ''
 registration_shared_secret: "${cfg.registration_shared_secret}"
 ''}
@@ -78,15 +77,15 @@ recaptcha_siteverify_api: "https://www.google.com/recaptcha/api/siteverify"
 turn_user_lifetime: "${cfg.turn_user_lifetime}"
 user_creation_max_duration: ${cfg.user_creation_max_duration}
 bcrypt_rounds: ${cfg.bcrypt_rounds}
-allow_guest_access: ${fromBool cfg.allow_guest_access}
+allow_guest_access: ${boolToString cfg.allow_guest_access}
 trusted_third_party_id_servers: ${builtins.toJSON cfg.trusted_third_party_id_servers}
 room_invite_state_types: ${builtins.toJSON cfg.room_invite_state_types}
 ${optionalString (cfg.macaroon_secret_key != null) ''
   macaroon_secret_key: "${cfg.macaroon_secret_key}"
 ''}
-expire_access_token: ${fromBool cfg.expire_access_token}
-enable_metrics: ${fromBool cfg.enable_metrics}
-report_stats: ${fromBool cfg.report_stats}
+expire_access_token: ${boolToString cfg.expire_access_token}
+enable_metrics: ${boolToString cfg.enable_metrics}
+report_stats: ${boolToString cfg.report_stats}
 signing_key_path: "/var/lib/matrix-synapse/homeserver.signing.key"
 key_refresh_interval: "${cfg.key_refresh_interval}"
 perspectives:
diff --git a/nixos/modules/services/misc/nix-daemon.nix b/nixos/modules/services/misc/nix-daemon.nix
index 4fe89838e29..bf1304ee7ac 100644
--- a/nixos/modules/services/misc/nix-daemon.nix
+++ b/nixos/modules/services/misc/nix-daemon.nix
@@ -41,12 +41,12 @@ let
         build-users-group = nixbld
         build-max-jobs = ${toString (cfg.maxJobs)}
         build-cores = ${toString (cfg.buildCores)}
-        build-use-sandbox = ${if (builtins.isBool cfg.useSandbox) then (if cfg.useSandbox then "true" else "false") else cfg.useSandbox}
+        build-use-sandbox = ${if (builtins.isBool cfg.useSandbox) then boolToString cfg.useSandbox else cfg.useSandbox}
         build-sandbox-paths = ${toString cfg.sandboxPaths} /bin/sh=${sh} $(echo $extraPaths)
         binary-caches = ${toString cfg.binaryCaches}
         trusted-binary-caches = ${toString cfg.trustedBinaryCaches}
         binary-cache-public-keys = ${toString cfg.binaryCachePublicKeys}
-        auto-optimise-store = ${if cfg.autoOptimiseStore then "true" else "false"}
+        auto-optimise-store = ${boolToString cfg.autoOptimiseStore}
         ${optionalString cfg.requireSignedBinaryCaches ''
           signed-binary-caches = *
         ''}
diff --git a/nixos/modules/services/misc/taskserver/default.nix b/nixos/modules/services/misc/taskserver/default.nix
index ba9f52f1904..ab9a6ce32f4 100644
--- a/nixos/modules/services/misc/taskserver/default.nix
+++ b/nixos/modules/services/misc/taskserver/default.nix
@@ -128,7 +128,7 @@ let
         certBits = cfg.pki.auto.bits;
         clientExpiration = cfg.pki.auto.expiration.client;
         crlExpiration = cfg.pki.auto.expiration.crl;
-        isAutoConfig = if needToCreateCA then "True" else "False";
+        isAutoConfig = boolToString needToCreateCA;
       }}" > "$out/main.py"
       cat > "$out/setup.py" <<EOF
       from setuptools import setup
diff --git a/nixos/modules/services/monitoring/collectd.nix b/nixos/modules/services/monitoring/collectd.nix
index 641da60e9ad..79a8a1ff5ae 100644
--- a/nixos/modules/services/monitoring/collectd.nix
+++ b/nixos/modules/services/monitoring/collectd.nix
@@ -8,7 +8,7 @@ let
   conf = pkgs.writeText "collectd.conf" ''
     BaseDir "${cfg.dataDir}"
     PIDFile "${cfg.pidFile}"
-    AutoLoadPlugin ${if cfg.autoLoadPlugin then "true" else "false"}
+    AutoLoadPlugin ${boolToString cfg.autoLoadPlugin}
     Hostname "${config.networking.hostName}"
 
     LoadPlugin syslog
diff --git a/nixos/modules/services/monitoring/grafana.nix b/nixos/modules/services/monitoring/grafana.nix
index 97806d5d83e..4fbacef788f 100644
--- a/nixos/modules/services/monitoring/grafana.nix
+++ b/nixos/modules/services/monitoring/grafana.nix
@@ -5,8 +5,6 @@ with lib;
 let
   cfg = config.services.grafana;
 
-  b2s = val: if val then "true" else "false";
-
   envOptions = {
     PATHS_DATA = cfg.dataDir;
     PATHS_PLUGINS = "${cfg.dataDir}/plugins";
@@ -32,16 +30,16 @@ let
     SECURITY_ADMIN_PASSWORD = cfg.security.adminPassword;
     SECURITY_SECRET_KEY = cfg.security.secretKey;
 
-    USERS_ALLOW_SIGN_UP = b2s cfg.users.allowSignUp;
-    USERS_ALLOW_ORG_CREATE = b2s cfg.users.allowOrgCreate;
-    USERS_AUTO_ASSIGN_ORG = b2s cfg.users.autoAssignOrg;
+    USERS_ALLOW_SIGN_UP = boolToString cfg.users.allowSignUp;
+    USERS_ALLOW_ORG_CREATE = boolToString cfg.users.allowOrgCreate;
+    USERS_AUTO_ASSIGN_ORG = boolToString cfg.users.autoAssignOrg;
     USERS_AUTO_ASSIGN_ORG_ROLE = cfg.users.autoAssignOrgRole;
 
-    AUTH_ANONYMOUS_ENABLED = b2s cfg.auth.anonymous.enable;
+    AUTH_ANONYMOUS_ENABLED = boolToString cfg.auth.anonymous.enable;
     AUTH_ANONYMOUS_ORG_NAME = cfg.auth.anonymous.org_name;
     AUTH_ANONYMOUS_ORG_ROLE = cfg.auth.anonymous.org_role;
 
-    ANALYTICS_REPORTING_ENABLED = b2s cfg.analytics.reporting.enable;
+    ANALYTICS_REPORTING_ENABLED = boolToString cfg.analytics.reporting.enable;
   } // cfg.extraOptions;
 
 in {
diff --git a/nixos/modules/services/network-filesystems/netatalk.nix b/nixos/modules/services/network-filesystems/netatalk.nix
index bff54406a2b..1dd869043f0 100644
--- a/nixos/modules/services/network-filesystems/netatalk.nix
+++ b/nixos/modules/services/network-filesystems/netatalk.nix
@@ -9,7 +9,7 @@ let
   extmapFile = pkgs.writeText "extmap.conf" cfg.extmap;
 
   afpToString = x: if builtins.typeOf x == "bool"
-                   then (if x then "true" else "false")
+                   then boolToString x
                    else toString x;
 
   volumeConfig = name:
diff --git a/nixos/modules/services/network-filesystems/samba.nix b/nixos/modules/services/network-filesystems/samba.nix
index 6ae5292fc30..87c4f7a8ebc 100644
--- a/nixos/modules/services/network-filesystems/samba.nix
+++ b/nixos/modules/services/network-filesystems/samba.nix
@@ -5,7 +5,7 @@ with lib;
 let
 
   smbToString = x: if builtins.typeOf x == "bool"
-                   then (if x then "true" else "false")
+                   then boolToString x
                    else toString x;
 
   cfg = config.services.samba;
diff --git a/nixos/modules/services/network-filesystems/tahoe.nix b/nixos/modules/services/network-filesystems/tahoe.nix
index 3d78ac096a2..9815a5434ee 100644
--- a/nixos/modules/services/network-filesystems/tahoe.nix
+++ b/nixos/modules/services/network-filesystems/tahoe.nix
@@ -290,14 +290,14 @@ in
                 shares.total = ${toString settings.client.shares.total}
 
                 [storage]
-                enabled = ${if settings.storage.enable then "true" else "false"}
+                enabled = ${boolToString settings.storage.enable}
                 reserved_space = ${settings.storage.reservedSpace}
 
                 [helper]
-                enabled = ${if settings.helper.enable then "true" else "false"}
+                enabled = ${boolToString settings.helper.enable}
 
                 [sftpd]
-                enabled = ${if settings.sftpd.enable then "true" else "false"}
+                enabled = ${boolToString settings.sftpd.enable}
                 ${optionalString (settings.sftpd.port != null)
                   "port = ${toString settings.sftpd.port}"}
                 ${optionalString (settings.sftpd.hostPublicKeyFile != null)
diff --git a/nixos/modules/services/networking/aiccu.nix b/nixos/modules/services/networking/aiccu.nix
index aeb0910d624..ac755270951 100644
--- a/nixos/modules/services/networking/aiccu.nix
+++ b/nixos/modules/services/networking/aiccu.nix
@@ -5,7 +5,6 @@ with lib;
 let
 
   cfg = config.services.aiccu;
-  showBool = b: if b then "true" else "false";
   notNull = a: ! isNull a;
   configFile = pkgs.writeText "aiccu.conf" ''
     ${if notNull cfg.username then "username " + cfg.username else ""}
@@ -13,16 +12,16 @@ let
     protocol ${cfg.protocol}
     server ${cfg.server}
     ipv6_interface ${cfg.interfaceName}
-    verbose ${showBool cfg.verbose}
+    verbose ${boolToString cfg.verbose}
     daemonize true
-    automatic ${showBool cfg.automatic}
-    requiretls ${showBool cfg.requireTLS}
+    automatic ${boolToString cfg.automatic}
+    requiretls ${boolToString cfg.requireTLS}
     pidfile ${cfg.pidFile}
-    defaultroute ${showBool cfg.defaultRoute}
+    defaultroute ${boolToString cfg.defaultRoute}
     ${if notNull cfg.setupScript then cfg.setupScript else ""}
-    makebeats ${showBool cfg.makeHeartBeats}
-    noconfigure ${showBool cfg.noConfigure}
-    behindnat ${showBool cfg.behindNAT}
+    makebeats ${boolToString cfg.makeHeartBeats}
+    noconfigure ${boolToString cfg.noConfigure}
+    behindnat ${boolToString cfg.behindNAT}
     ${if cfg.localIPv4Override then "local_ipv4_override" else ""}
   '';
 
diff --git a/nixos/modules/services/networking/btsync.nix b/nixos/modules/services/networking/btsync.nix
index 92e9fa7be41..6e479a5860a 100644
--- a/nixos/modules/services/networking/btsync.nix
+++ b/nixos/modules/services/networking/btsync.nix
@@ -9,7 +9,6 @@ let
 
   listenAddr = cfg.httpListenAddr + ":" + (toString cfg.httpListenPort);
 
-  boolStr = x: if x then "true" else "false";
   optionalEmptyStr = b: v: optionalString (b != "") v;
 
   webUIConfig = optionalString cfg.enableWebUI
@@ -31,7 +30,7 @@ let
   sharedFoldersRecord =
     concatStringsSep "," (map (entry:
       let helper = attr: v:
-        if (entry ? attr) then boolStr entry.attr else boolStr v;
+        if (entry ? attr) then boolToString entry.attr else boolToString v;
       in
       ''
         {
@@ -65,11 +64,11 @@ let
         "listening_port":  ${toString cfg.listeningPort},
         "use_gui":         false,
 
-        "check_for_updates": ${boolStr cfg.checkForUpdates},
-        "use_upnp":          ${boolStr cfg.useUpnp},
+        "check_for_updates": ${boolToString cfg.checkForUpdates},
+        "use_upnp":          ${boolToString cfg.useUpnp},
         "download_limit":    ${toString cfg.downloadLimit},
         "upload_limit":      ${toString cfg.uploadLimit},
-        "lan_encrypt_data":  ${boolStr cfg.encryptLAN},
+        "lan_encrypt_data":  ${boolToString cfg.encryptLAN},
 
         ${webUIConfig}
         ${sharedFoldersConfig}
diff --git a/nixos/modules/services/networking/firefox/sync-server.nix b/nixos/modules/services/networking/firefox/sync-server.nix
index 5c14ceff6a0..3a95b9c4ec9 100644
--- a/nixos/modules/services/networking/firefox/sync-server.nix
+++ b/nixos/modules/services/networking/firefox/sync-server.nix
@@ -19,7 +19,7 @@ let
     [syncserver]
     public_url = ${cfg.publicUrl}
     ${optionalString (cfg.sqlUri != "") "sqluri = ${cfg.sqlUri}"}
-    allow_new_users = ${if cfg.allowNewUsers then "true" else "false"}
+    allow_new_users = ${boolToString cfg.allowNewUsers}
 
     [browserid]
     backend = tokenserver.verifiers.LocalVerifier
diff --git a/nixos/modules/services/networking/i2pd.nix b/nixos/modules/services/networking/i2pd.nix
index c5b27350b3c..24a3196bed4 100644
--- a/nixos/modules/services/networking/i2pd.nix
+++ b/nixos/modules/services/networking/i2pd.nix
@@ -10,8 +10,6 @@ let
 
   extip = "EXTIP=\$(${pkgs.curl.bin}/bin/curl -sLf \"http://jsonip.com\" | ${pkgs.gawk}/bin/awk -F'\"' '{print $4}')";
 
-  toYesNo = b: if b then "true" else "false";
-
   mkEndpointOpt = name: addr: port: {
     enable = mkEnableOption name;
     name = mkOption {
@@ -76,10 +74,10 @@ let
 
   i2pdConf = pkgs.writeText "i2pd.conf"
   ''
-  ipv4 = ${toYesNo cfg.enableIPv4}
-  ipv6 = ${toYesNo cfg.enableIPv6}
-  notransit = ${toYesNo cfg.notransit}
-  floodfill = ${toYesNo cfg.floodfill}
+  ipv4 = ${boolToString cfg.enableIPv4}
+  ipv6 = ${boolToString cfg.enableIPv6}
+  notransit = ${boolToString cfg.notransit}
+  floodfill = ${boolToString cfg.floodfill}
   netid = ${toString cfg.netid}
   ${if isNull cfg.bandwidth then "" else "bandwidth = ${toString cfg.bandwidth}" }
   ${if isNull cfg.port then "" else "port = ${toString cfg.port}"}
@@ -88,14 +86,14 @@ let
   transittunnels = ${toString cfg.limits.transittunnels}
 
   [upnp]
-  enabled = ${toYesNo cfg.upnp.enable}
+  enabled = ${boolToString cfg.upnp.enable}
   name = ${cfg.upnp.name}
 
   [precomputation]
-  elgamal = ${toYesNo cfg.precomputation.elgamal}
+  elgamal = ${boolToString cfg.precomputation.elgamal}
 
   [reseed]
-  verify = ${toYesNo cfg.reseed.verify}
+  verify = ${boolToString cfg.reseed.verify}
   file = ${cfg.reseed.file}
   urls = ${builtins.concatStringsSep "," cfg.reseed.urls}
 
@@ -107,11 +105,11 @@ let
       (proto: let portStr = toString proto.port; in
         ''
           [${proto.name}]
-          enabled = ${toYesNo proto.enable}
+          enabled = ${boolToString proto.enable}
           address = ${proto.address}
           port = ${toString proto.port}
           ${if proto ? keys then "keys = ${proto.keys}" else ""}
-          ${if proto ? auth then "auth = ${toYesNo proto.auth}" else ""}
+          ${if proto ? auth then "auth = ${boolToString proto.auth}" else ""}
           ${if proto ? user then "user = ${proto.user}" else ""}
           ${if proto ? pass then "pass = ${proto.pass}" else ""}
           ${if proto ? outproxy then "outproxy = ${proto.outproxy}" else ""}
diff --git a/nixos/modules/services/networking/ircd-hybrid/default.nix b/nixos/modules/services/networking/ircd-hybrid/default.nix
index ede57c5046d..bd583fb020e 100644
--- a/nixos/modules/services/networking/ircd-hybrid/default.nix
+++ b/nixos/modules/services/networking/ircd-hybrid/default.nix
@@ -12,7 +12,7 @@ let
     substFiles = [ "=>/conf" ./ircd.conf ];
     inherit (pkgs) ircdHybrid coreutils su iproute gnugrep procps;
 
-    ipv6Enabled = if config.networking.enableIPv6 then "true" else "false";
+    ipv6Enabled = boolToString config.networking.enableIPv6;
 
     inherit (cfg) serverName sid description adminEmail
             extraPort;
diff --git a/nixos/modules/services/networking/mosquitto.nix b/nixos/modules/services/networking/mosquitto.nix
index 2325424ff3c..5451500b56f 100644
--- a/nixos/modules/services/networking/mosquitto.nix
+++ b/nixos/modules/services/networking/mosquitto.nix
@@ -16,7 +16,7 @@ let
     pid_file /run/mosquitto/pid
     acl_file ${aclFile}
     persistence true
-    allow_anonymous ${if cfg.allowAnonymous then "true" else "false"}
+    allow_anonymous ${boolToString cfg.allowAnonymous}
     bind_address ${cfg.host}
     port ${toString cfg.port}
     ${listenerConf}
diff --git a/nixos/modules/services/networking/murmur.nix b/nixos/modules/services/networking/murmur.nix
index 81f968ae9fe..c961857c77a 100644
--- a/nixos/modules/services/networking/murmur.nix
+++ b/nixos/modules/services/networking/murmur.nix
@@ -26,21 +26,21 @@ let
 
     textmessagelength=${toString cfg.textMsgLength}
     imagemessagelength=${toString cfg.imgMsgLength}
-    allowhtml=${if cfg.allowHtml then "true" else "false"}
+    allowhtml=${boolToString cfg.allowHtml}
     logdays=${toString cfg.logDays}
-    bonjour=${if cfg.bonjour then "true" else "false"}
-    sendversion=${if cfg.sendVersion then "true" else "false"}
+    bonjour=${babelToString cfg.bonjour}
+    sendversion=${babelToString cfg.sendVersion}
 
     ${if cfg.registerName     == "" then "" else "registerName="+cfg.registerName}
     ${if cfg.registerPassword == "" then "" else "registerPassword="+cfg.registerPassword}
     ${if cfg.registerUrl      == "" then "" else "registerUrl="+cfg.registerUrl}
     ${if cfg.registerHostname == "" then "" else "registerHostname="+cfg.registerHostname}
 
-    certrequired=${if cfg.clientCertRequired then "true" else "false"}
+    certrequired=${babelToString cfg.clientCertRequired}
     ${if cfg.sslCert == "" then "" else "sslCert="+cfg.sslCert}
     ${if cfg.sslKey  == "" then "" else "sslKey="+cfg.sslKey}
     ${if cfg.sslCa   == "" then "" else "sslCA="+cfg.sslCa}
-    
+
     ${cfg.extraConfig}
   '';
 in
diff --git a/nixos/modules/services/networking/prosody.nix b/nixos/modules/services/networking/prosody.nix
index feaa007de15..fb9c9dc67f2 100644
--- a/nixos/modules/services/networking/prosody.nix
+++ b/nixos/modules/services/networking/prosody.nix
@@ -219,7 +219,7 @@ in
 
       data_path = "/var/lib/prosody"
 
-      allow_registration = ${ if cfg.allowRegistration then "true" else "false" };
+      allow_registration = ${boolToString cfg.allowRegistration};
 
       ${ optionalString cfg.modules.console "console_enabled = true;" }
 
@@ -244,7 +244,7 @@ in
 
       ${ lib.concatStringsSep "\n" (lib.mapAttrsToList (n: v: ''
         VirtualHost "${v.domain}"
-          enabled = ${if v.enabled then "true" else "false"};
+          enabled = ${boolToString v.enabled};
           ${ optionalString (v.ssl != null) (createSSLOptsStr v.ssl) }
           ${ v.extraConfig }
         '') cfg.virtualHosts) }
diff --git a/nixos/modules/services/networking/sslh.nix b/nixos/modules/services/networking/sslh.nix
index bd584a3a85d..e3d65c49fbf 100644
--- a/nixos/modules/services/networking/sslh.nix
+++ b/nixos/modules/services/networking/sslh.nix
@@ -5,7 +5,7 @@ with lib;
 let
   cfg = config.services.sslh;
   configFile = pkgs.writeText "sslh.conf" ''
-    verbose: ${if cfg.verbose then "true" else "false"};
+    verbose: ${boolToString cfg.verbose};
     foreground: true;
     inetd: false;
     numeric: false;
diff --git a/nixos/modules/services/networking/znc.nix b/nixos/modules/services/networking/znc.nix
index 6d68b790e86..1c63d800e26 100644
--- a/nixos/modules/services/networking/znc.nix
+++ b/nixos/modules/services/networking/znc.nix
@@ -35,7 +35,7 @@ let
             Port = ${toString confOpts.port}
             IPv4 = true
             IPv6 = true
-            SSL = ${if confOpts.useSSL then "true" else "false"}
+            SSL = ${boolToString confOpts.useSSL}
     </Listener>
     
     <User ${confOpts.userName}>
diff --git a/nixos/modules/services/security/oauth2_proxy.nix b/nixos/modules/services/security/oauth2_proxy.nix
index caa7d9d5081..e292fd9851e 100644
--- a/nixos/modules/services/security/oauth2_proxy.nix
+++ b/nixos/modules/services/security/oauth2_proxy.nix
@@ -10,9 +10,6 @@ let
   #   repeatedArgs (arg: "--arg=${arg}") args
   repeatedArgs = concatMapStringsSep " ";
 
-  # 'toString' doesn't quite do what we want for bools.
-  fromBool = x: if x then "true" else "false";
-
   # oauth2_proxy provides many options that are only relevant if you are using
   # a certain provider. This set maps from provider name to a function that
   # takes the configuration and returns a string that can be inserted into the
@@ -49,24 +46,24 @@ let
     --client-secret='${cfg.clientSecret}' \
     ${optionalString (!isNull cfg.cookie.domain) "--cookie-domain='${cfg.cookie.domain}'"} \
     --cookie-expire='${cfg.cookie.expire}' \
-    --cookie-httponly=${fromBool cfg.cookie.httpOnly} \
+    --cookie-httponly=${boolToString cfg.cookie.httpOnly} \
     --cookie-name='${cfg.cookie.name}' \
     --cookie-secret='${cfg.cookie.secret}' \
-    --cookie-secure=${fromBool cfg.cookie.secure} \
+    --cookie-secure=${boolToString cfg.cookie.secure} \
     ${optionalString (!isNull cfg.cookie.refresh) "--cookie-refresh='${cfg.cookie.refresh}'"} \
     ${optionalString (!isNull cfg.customTemplatesDir) "--custom-templates-dir='${cfg.customTemplatesDir}'"} \
     ${repeatedArgs (x: "--email-domain='${x}'") cfg.email.domains} \
     --http-address='${cfg.httpAddress}' \
-    ${optionalString (!isNull cfg.htpasswd.file) "--htpasswd-file='${cfg.htpasswd.file}' --display-htpasswd-form=${fromBool cfg.htpasswd.displayForm}"} \
+    ${optionalString (!isNull cfg.htpasswd.file) "--htpasswd-file='${cfg.htpasswd.file}' --display-htpasswd-form=${boolToString cfg.htpasswd.displayForm}"} \
     ${optionalString (!isNull cfg.loginURL) "--login-url='${cfg.loginURL}'"} \
-    --pass-access-token=${fromBool cfg.passAccessToken} \
-    --pass-basic-auth=${fromBool cfg.passBasicAuth} \
-    --pass-host-header=${fromBool cfg.passHostHeader} \
+    --pass-access-token=${boolToString cfg.passAccessToken} \
+    --pass-basic-auth=${boolToString cfg.passBasicAuth} \
+    --pass-host-header=${boolToString cfg.passHostHeader} \
     --proxy-prefix='${cfg.proxyPrefix}' \
     ${optionalString (!isNull cfg.profileURL) "--profile-url='${cfg.profileURL}'"} \
     ${optionalString (!isNull cfg.redeemURL) "--redeem-url='${cfg.redeemURL}'"} \
     ${optionalString (!isNull cfg.redirectURL) "--redirect-url='${cfg.redirectURL}'"} \
-    --request-logging=${fromBool cfg.requestLogging} \
+    --request-logging=${boolToString cfg.requestLogging} \
     ${optionalString (!isNull cfg.scope) "--scope='${cfg.scope}'"} \
     ${repeatedArgs (x: "--skip-auth-regex='${x}'") cfg.skipAuthRegexes} \
     ${optionalString (!isNull cfg.signatureKey) "--signature-key='${cfg.signatureKey}'"} \
diff --git a/nixos/modules/services/torrent/transmission.nix b/nixos/modules/services/torrent/transmission.nix
index 5b2e4ca1606..1f319df794b 100644
--- a/nixos/modules/services/torrent/transmission.nix
+++ b/nixos/modules/services/torrent/transmission.nix
@@ -15,8 +15,7 @@ let
 
   # Strings must be quoted, ints and bools must not (for settings.json).
   toOption = x:
-    if x == true then "true"
-    else if x == false then "false"
+    if isBool x then boolToString x
     else if isInt x then toString x
     else toString ''"${x}"'';
 
diff --git a/nixos/modules/services/web-apps/atlassian/crowd.nix b/nixos/modules/services/web-apps/atlassian/crowd.nix
index ce41aa4f1e1..b54c91d7de9 100644
--- a/nixos/modules/services/web-apps/atlassian/crowd.nix
+++ b/nixos/modules/services/web-apps/atlassian/crowd.nix
@@ -137,7 +137,7 @@ in
 
         sed -e 's,port="8095",port="${toString cfg.listenPort}" address="${cfg.listenAddress}",' \
         '' + (lib.optionalString cfg.proxy.enable ''
-          -e 's,compression="on",compression="off" protocol="HTTP/1.1" proxyName="${cfg.proxy.name}" proxyPort="${toString cfg.proxy.port}" scheme="${cfg.proxy.scheme}" secure="${if cfg.proxy.secure then "true" else "false"}",' \
+          -e 's,compression="on",compression="off" protocol="HTTP/1.1" proxyName="${cfg.proxy.name}" proxyPort="${toString cfg.proxy.port}" scheme="${cfg.proxy.scheme}" secure="${boolToString cfg.proxy.secure}",' \
         '') + ''
           ${pkg}/apache-tomcat/conf/server.xml.dist > ${cfg.home}/server.xml
       '';
diff --git a/nixos/modules/services/web-apps/quassel-webserver.nix b/nixos/modules/services/web-apps/quassel-webserver.nix
index d19e4bc5827..2ba5698d6cb 100644
--- a/nixos/modules/services/web-apps/quassel-webserver.nix
+++ b/nixos/modules/services/web-apps/quassel-webserver.nix
@@ -12,11 +12,11 @@ let
         port: ${toString cfg.quasselCorePort},  // quasselcore port
         initialBacklogLimit: ${toString cfg.initialBacklogLimit},  // Amount of backlogs to fetch per buffer on connection
         backlogLimit: ${toString cfg.backlogLimit},  // Amount of backlogs to fetch per buffer after first retrieval
-        securecore: ${if cfg.secureCore then "true" else "false"},  // Connect to the core using SSL
+        securecore: ${boolToString cfg.secureCore},  // Connect to the core using SSL
         theme: '${cfg.theme}'  // Default UI theme
       },
       themes: ['default', 'darksolarized'],  //  Available themes
-      forcedefault: ${if cfg.forceHostAndPort then "true" else "false"},  // Will force default host and port to be used, and will hide the corresponding fields in the UI
+      forcedefault: ${boolToString cfg.forceHostAndPort},  // Will force default host and port to be used, and will hide the corresponding fields in the UI
       prefixpath: '${cfg.prefixPath}'  // Configure this if you use a reverse proxy
     };
   '';
diff --git a/nixos/modules/services/web-apps/tt-rss.nix b/nixos/modules/services/web-apps/tt-rss.nix
index 5193814da72..76b0ee6da96 100644
--- a/nixos/modules/services/web-apps/tt-rss.nix
+++ b/nixos/modules/services/web-apps/tt-rss.nix
@@ -6,8 +6,6 @@ let
 
   configVersion = 26;
 
-  boolToString = b: if b then "true" else "false";
-
   cacheDir = "cache";
   lockDir = "lock";
   feedIconsDir = "feed-icons";
diff --git a/nixos/modules/services/x11/display-managers/sddm.nix b/nixos/modules/services/x11/display-managers/sddm.nix
index affc1261d19..99c03ca81c2 100644
--- a/nixos/modules/services/x11/display-managers/sddm.nix
+++ b/nixos/modules/services/x11/display-managers/sddm.nix
@@ -59,7 +59,7 @@ let
     [Autologin]
     User=${cfg.autoLogin.user}
     Session=${defaultSessionName}.desktop
-    Relogin=${if cfg.autoLogin.relogin then "true" else "false"}
+    Relogin=${boolToString cfg.autoLogin.relogin}
     ''}
 
     ${cfg.extraConfig}
diff --git a/nixos/modules/services/x11/hardware/multitouch.nix b/nixos/modules/services/x11/hardware/multitouch.nix
index 0e9eb021494..c03bb3b494f 100644
--- a/nixos/modules/services/x11/hardware/multitouch.nix
+++ b/nixos/modules/services/x11/hardware/multitouch.nix
@@ -74,7 +74,7 @@ in {
           MatchIsTouchpad "on"
           Identifier "Touchpads"
           Driver "mtrack"
-          Option "IgnorePalm" "${if cfg.ignorePalm then "true" else "false"}"
+          Option "IgnorePalm" "${boolToString cfg.ignorePalm}"
           Option "ClickFinger1" "${builtins.elemAt cfg.buttonsMap 0}"
           Option "ClickFinger2" "${builtins.elemAt cfg.buttonsMap 1}"
           Option "ClickFinger3" "${builtins.elemAt cfg.buttonsMap 2}"
diff --git a/pkgs/development/java-modules/build-maven-package.nix b/pkgs/development/java-modules/build-maven-package.nix
index d83b43ffd75..b3c3e1732e0 100644
--- a/pkgs/development/java-modules/build-maven-package.nix
+++ b/pkgs/development/java-modules/build-maven-package.nix
@@ -27,7 +27,7 @@ in stdenv.mkDerivation rec {
     echo "<settings><mirrors>\
       <mirror><id>tmpm2</id><url>file://$out/m2</url><mirrorOf>*</mirrorOf></mirror></mirrors>\
       <localRepository>$out/m2/</localRepository></settings>" >> $out/m2/settings.xml
-    ${maven}/bin/mvn ${optionalString (quiet) "-q"} clean package -Dmaven.test.skip=${if skipTests then "true" else "false"} -Danimal.sniffer.skip=true -gs $out/m2/settings.xml
+    ${maven}/bin/mvn ${optionalString (quiet) "-q"} clean package -Dmaven.test.skip=${boolToString skipTests} -Danimal.sniffer.skip=true -gs $out/m2/settings.xml
     cp ./target/*.jar $out/m2/${m2Path}
     cp -v ./target/*.jar $out/target/
   '';
diff --git a/pkgs/development/ocaml-modules/mtime/default.nix b/pkgs/development/ocaml-modules/mtime/default.nix
index a26109bd4f9..5e18d1fd6e4 100644
--- a/pkgs/development/ocaml-modules/mtime/default.nix
+++ b/pkgs/development/ocaml-modules/mtime/default.nix
@@ -1,7 +1,9 @@
-{ stdenv, fetchurl, ocaml, findlib, ocamlbuild, opam, js_of_ocaml
+{ stdenv, lib, fetchurl, ocaml, findlib, ocamlbuild, opam, js_of_ocaml
 , jsooSupport ? !(stdenv.lib.versionAtLeast ocaml.version "4.04")
 }:
 
+with lib;
+
 stdenv.mkDerivation {
   name = "ocaml${ocaml.version}-mtime-0.8.3";
 
@@ -15,7 +17,7 @@ stdenv.mkDerivation {
   buildInputs = [ ocaml findlib ocamlbuild opam ]
   ++ stdenv.lib.optional jsooSupport js_of_ocaml;
 
-  buildPhase = "ocaml pkg/build.ml native=true native-dynlink=true jsoo=${if jsooSupport then "true" else "false"}";
+  buildPhase = "ocaml pkg/build.ml native=true native-dynlink=true jsoo=${boolToString jsooSupport}";
 
   installPhase = "opam-installer -i --prefix=$out --libdir=$OCAMLFIND_DESTDIR";
 
@@ -23,7 +25,7 @@ stdenv.mkDerivation {
     description = "Monotonic wall-clock time for OCaml";
     homepage = http://erratique.ch/software/mtime;
     inherit (ocaml.meta) platforms;
-    maintainers = [ stdenv.lib.maintainers.vbgl ];
-    license = stdenv.lib.licenses.bsd3;
+    maintainers = [ maintainers.vbgl ];
+    license = licenses.bsd3;
   };
 }
diff --git a/pkgs/development/ocaml-modules/nocrypto/default.nix b/pkgs/development/ocaml-modules/nocrypto/default.nix
index f9240f7507c..91ab694eb6f 100644
--- a/pkgs/development/ocaml-modules/nocrypto/default.nix
+++ b/pkgs/development/ocaml-modules/nocrypto/default.nix
@@ -24,7 +24,7 @@ stdenv.mkDerivation rec {
 
   buildPhase = ''
     LD_LIBRARY_PATH=${cpuid}/lib/ocaml/${ocaml.version}/site-lib/stubslibs/ \
-    ${topkg.buildPhase} --with-lwt ${if withLwt then "true" else "false"}
+    ${topkg.buildPhase} --with-lwt ${boolToString withLwt}
   '';
   inherit (topkg) installPhase;
 
diff --git a/pkgs/development/ocaml-modules/notty/default.nix b/pkgs/development/ocaml-modules/notty/default.nix
index b967728d048..950395bd7ea 100644
--- a/pkgs/development/ocaml-modules/notty/default.nix
+++ b/pkgs/development/ocaml-modules/notty/default.nix
@@ -29,7 +29,7 @@ buildOcaml rec {
                           optional withLwt lwt;
 
   buildPhase = topkg.buildPhase
-  + " --with-lwt ${if withLwt then "true" else "false"}";
+  + " --with-lwt ${boolToString withLwt}";
 
   inherit (topkg) installPhase;
 
diff --git a/pkgs/development/ocaml-modules/vg/default.nix b/pkgs/development/ocaml-modules/vg/default.nix
index cb7878ac731..ba33081486d 100644
--- a/pkgs/development/ocaml-modules/vg/default.nix
+++ b/pkgs/development/ocaml-modules/vg/default.nix
@@ -1,16 +1,17 @@
-{ stdenv, fetchurl, ocaml, findlib, ocamlbuild, opam, topkg
+{ stdenv, lib, fetchurl, ocaml, findlib, ocamlbuild, opam, topkg
 , uchar, result, gg, uutf, otfm, js_of_ocaml,
   pdfBackend ? true, # depends on uutf and otfm
   htmlcBackend ? true # depends on js_of_ocaml
 }:
 
+with lib;
+
 let
   inherit (stdenv.lib) optionals versionAtLeast;
 
   pname = "vg";
   version = "0.9.0";
   webpage = "http://erratique.ch/software/${pname}";
-  sob = b: if b then "true" else "false";
 in
 
 assert versionAtLeast ocaml.version "4.02.0";
@@ -35,13 +36,14 @@ stdenv.mkDerivation rec {
   unpackCmd = "tar xjf $src";
 
   buildPhase = topkg.buildPhase
-  + " --with-uutf ${sob pdfBackend} --with-otfm ${sob pdfBackend}"
-  + " --with-js_of_ocaml ${sob htmlcBackend}"
-  + " --with-cairo2 false";
+    + " --with-uutf ${boolToString pdfBackend}"
+    + " --with-otfm ${boolToString pdfBackend}"
+    + " --with-js_of_ocaml ${boolToString htmlcBackend}"
+    + " --with-cairo2 false";
 
   inherit (topkg) installPhase;
 
-  meta = with stdenv.lib; {
+  meta = {
     description = "Declarative 2D vector graphics for OCaml";
     longDescription = ''
     Vg is an OCaml module for declarative 2D vector graphics. In Vg, images