diff --git a/app/src/api/building.js b/app/src/api/building.js
index 9008dc69..ed47d6b5 100644
--- a/app/src/api/building.js
+++ b/app/src/api/building.js
@@ -31,14 +31,14 @@ function queryBuildingsAtPoint(lng, lat) {
             )
         `,
         [lng, lat]
-    ).catch(function(error){
+    ).catch(function (error) {
         console.error(error);
         return undefined;
     });
 }
 
 function queryBuildingsByReference(key, id) {
-    if (key === 'toid'){
+    if (key === 'toid') {
         return db.manyOrNone(
             `SELECT
                 *
@@ -48,7 +48,7 @@ function queryBuildingsByReference(key, id) {
                 ref_toid = $1
             `,
             [id]
-        ).catch(function(error){
+        ).catch(function (error) {
             console.error(error);
             return undefined;
         });
@@ -65,19 +65,19 @@ function queryBuildingsByReference(key, id) {
                 p.uprn = $1
             `,
             [id]
-        ).catch(function(error){
+        ).catch(function (error) {
             console.error(error);
             return undefined;
         });
     }
-    return {error: 'Key must be UPRN or TOID'};
+    return { error: 'Key must be UPRN or TOID' };
 }
 
 function getBuildingById(id) {
     return db.one(
         "SELECT * FROM buildings WHERE building_id = $1",
         [id]
-    ).catch(function(error){
+    ).catch(function (error) {
         console.error(error);
         return undefined;
     });
@@ -89,7 +89,7 @@ function getBuildingLikeById(building_id, user_id) {
         [building_id, user_id]
     ).then(res => {
         return res && res.like
-    }).catch(function(error){
+    }).catch(function (error) {
         console.error(error);
         return undefined;
     });
@@ -99,7 +99,7 @@ function getBuildingUPRNsById(id) {
     return db.any(
         "SELECT uprn, parent_uprn FROM building_properties WHERE building_id = $1",
         [id]
-    ).catch(function(error){
+    ).catch(function (error) {
         console.error(error);
         return undefined;
     });
@@ -160,10 +160,9 @@ function saveBuilding(building_id, building, user_id) {
                 )
             });
         });
-    }).catch(function(error){
-        // TODO report transaction error as 'Need to re-fetch building before update'
+    }).catch(function (error) {
         console.error(error);
-        return {error: error};
+        return { error: error };
     });
 }
 
@@ -175,7 +174,7 @@ function likeBuilding(building_id, user_id) {
     // - insert changeset
     // - update building to latest state
     // commit or rollback (serializable - could be more compact?)
-    return db.tx({serializable}, t => {
+    return db.tx({ serializable }, t => {
         return t.none(
             "INSERT INTO building_user_likes ( building_id, user_id ) VALUES ($1, $2);",
             [building_id, user_id]
@@ -191,7 +190,7 @@ function likeBuilding(building_id, user_id) {
                         $1:json, $2, $3
                     ) RETURNING log_id
                     `,
-                    [{likes_total: building.likes}, building_id, user_id]
+                    [{ likes_total: building.likes }, building_id, user_id]
                 ).then(revision => {
                     return t.one(
                         `UPDATE buildings
@@ -208,12 +207,11 @@ function likeBuilding(building_id, user_id) {
                 })
             });
         });
-    }).catch(function(error){
-        // TODO report transaction error as 'Need to re-fetch building before update'
+    }).catch(function (error) {
         console.error(error);
-        if (error.detail && error.detail.includes("already exists")){
+        if (error.detail && error.detail.includes("already exists")) {
             // 'already exists' is thrown if user already liked it
-            return {error: 'It looks like you already like that building!'};
+            return { error: 'It looks like you already like that building!' };
         } else {
             return undefined
         }
@@ -228,7 +226,7 @@ function unlikeBuilding(building_id, user_id) {
     // - insert changeset
     // - update building to latest state
     // commit or rollback (serializable - could be more compact?)
-    return db.tx({serializable}, t => {
+    return db.tx({ serializable }, t => {
         return t.none(
             "DELETE FROM building_user_likes WHERE building_id = $1 AND user_id = $2;",
             [building_id, user_id]
@@ -244,7 +242,7 @@ function unlikeBuilding(building_id, user_id) {
                         $1:json, $2, $3
                     ) RETURNING log_id
                     `,
-                    [{likes_total: building.likes}, building_id, user_id]
+                    [{ likes_total: building.likes }, building_id, user_id]
                 ).then(revision => {
                     return t.one(
                         `UPDATE buildings
@@ -261,12 +259,11 @@ function unlikeBuilding(building_id, user_id) {
                 })
             });
         });
-    }).catch(function(error){
-        // TODO report transaction error as 'Need to re-fetch building before update'
+    }).catch(function (error) {
         console.error(error);
-        if (error.detail && error.detail.includes("already exists")){
+        if (error.detail && error.detail.includes("already exists")) {
             // 'already exists' is thrown if user already liked it
-            return {error: 'It looks like you already like that building!'};
+            return { error: 'It looks like you already like that building!' };
         } else {
             return undefined
         }
@@ -331,7 +328,7 @@ const BUILDING_FIELD_WHITELIST = new Set([
  * @param {Set} whitelist
  * @returns {[object, object]}
  */
-function compare(old_obj, new_obj, whitelist){
+function compare(old_obj, new_obj, whitelist) {
     const reverse_patch = {}
     const forward_patch = {}
     for (const [key, value] of Object.entries(new_obj)) {
diff --git a/app/src/api/search.js b/app/src/api/search.js
index 83138248..1aed1835 100644
--- a/app/src/api/search.js
+++ b/app/src/api/search.js
@@ -8,7 +8,7 @@
  */
 import db from '../db';
 
-function queryLocation(term){
+function queryLocation(term) {
     const max_results = 5;
     return db.manyOrNone(
         `SELECT
diff --git a/app/src/api/user.js b/app/src/api/user.js
index 303da882..0e0995e0 100644
--- a/app/src/api/user.js
+++ b/app/src/api/user.js
@@ -7,10 +7,10 @@ import db from '../db';
 
 function createUser(user) {
     if (!user.password || user.password.length < 8) {
-        return Promise.reject({error: 'Password must be at least 8 characters'})
+        return Promise.reject({ error: 'Password must be at least 8 characters' })
     }
     if (user.password.length > 70) {
-        return Promise.reject({error: 'Password must be at most 70 characters'})
+        return Promise.reject({ error: 'Password must be at most 70 characters' })
     }
     return db.one(
         `INSERT
@@ -26,21 +26,21 @@ function createUser(user) {
             crypt($3, gen_salt('bf'))
         ) RETURNING user_id
         `, [
-          user.username,
-          user.email,
-          user.password
+            user.username,
+            user.email,
+            user.password
         ]
-    ).catch(function(error){
+    ).catch(function (error) {
         console.error('Error:', error)
 
-        if (error.detail.indexOf('already exists') !== -1){
-            if (error.detail.indexOf('username') !== -1){
-                return {error:'Username already registered'};
+        if (error.detail.indexOf('already exists') !== -1) {
+            if (error.detail.indexOf('username') !== -1) {
+                return { error: 'Username already registered' };
             } else if (error.detail.indexOf('email') !== -1) {
-                return {error: 'Email already registered'};
+                return { error: 'Email already registered' };
             }
         }
-        return {error: 'Database error'}
+        return { error: 'Database error' }
     });
 }
 
@@ -55,18 +55,18 @@ function authUser(username, password) {
         WHERE
         username = $1
         `, [
-          username,
-          password
+            username,
+            password
         ]
-    ).then(function(user){
+    ).then(function (user) {
         if (user && user.auth_ok) {
-            return {user_id: user.user_id}
+            return { user_id: user.user_id }
         } else {
-            return {error: 'Username or password not recognised'}
+            return { error: 'Username or password not recognised' }
         }
-    }).catch(function(err){
+    }).catch(function (err) {
         console.error(err);
-        return {error: 'Username or password not recognised'};
+        return { error: 'Username or password not recognised' };
     })
 }
 
@@ -81,7 +81,7 @@ function getUserById(user_id) {
         `, [
             user_id
         ]
-    ).catch(function(error){
+    ).catch(function (error) {
         console.error('Error:', error)
         return undefined;
     });
@@ -100,9 +100,9 @@ function getNewUserAPIKey(user_id) {
         `, [
             user_id
         ]
-    ).catch(function(error){
+    ).catch(function (error) {
         console.error('Error:', error)
-        return {error: 'Failed to generate new API key.'};
+        return { error: 'Failed to generate new API key.' };
     });
 }
 
@@ -117,7 +117,7 @@ function authAPIUser(api_key) {
         `, [
             api_key
         ]
-    ).catch(function(error){
+    ).catch(function (error) {
         console.error('Error:', error)
         return undefined;
     });
diff --git a/app/src/parse.js b/app/src/parse.js
index 0b874fd6..4db75fc3 100644
--- a/app/src/parse.js
+++ b/app/src/parse.js
@@ -14,7 +14,7 @@ function strictParseInt(value) {
 }
 
 
-function parseBuildingURL(url){
+function parseBuildingURL(url) {
     const re = /\/building\/([^/]+).html/;
     const matches = re.exec(url);
 
@@ -30,7 +30,7 @@ function parseCategoryURL(url) {
         return default_cat
     }
     const matches = /^\/(view|edit)\/([^/.]+)/.exec(url);
-    const cat = (matches && matches.length >= 3)? matches[2] : default_cat;
+    const cat = (matches && matches.length >= 3) ? matches[2] : default_cat;
     return cat;
 }
 
diff --git a/app/src/server.js b/app/src/server.js
index a29aeea0..5bb44cdd 100644
--- a/app/src/server.js
+++ b/app/src/server.js
@@ -10,7 +10,7 @@ import express from 'express';
 import { renderToString } from 'react-dom/server';
 import serialize from 'serialize-javascript';
 
-import bodyParser  from 'body-parser';
+import bodyParser from 'body-parser';
 import session from 'express-session';
 import pgConnect from 'connect-pg-simple';
 
@@ -52,7 +52,7 @@ const sess = {
     name: 'cl.session',
     store: new pgSession({
         pgPromise: db,
-        tableName : 'user_sessions'
+        tableName: 'user_sessions'
     }),
     secret: process.env.APP_COOKIE_SECRET,
     saveUninitialized: false,
@@ -78,22 +78,22 @@ function frontendRoute(req, res) {
 
     const user_id = req.session.user_id;
     const building_id = parseBuildingURL(req.url);
-    const is_building = (typeof(building_id) !== "undefined");
-    if (is_building && isNaN(building_id)){
+    const is_building = (typeof (building_id) !== "undefined");
+    if (is_building && isNaN(building_id)) {
         context.status = 404;
     }
 
     Promise.all([
-        user_id? getUserById(user_id) : undefined,
-        is_building? getBuildingById(building_id) : undefined,
-        is_building? getBuildingUPRNsById(building_id) : undefined,
-        (is_building && user_id)? getBuildingLikeById(building_id, user_id) : false
-    ]).then(function(values){
+        user_id ? getUserById(user_id) : undefined,
+        is_building ? getBuildingById(building_id) : undefined,
+        is_building ? getBuildingUPRNsById(building_id) : undefined,
+        (is_building && user_id) ? getBuildingLikeById(building_id, user_id) : false
+    ]).then(function (values) {
         const user = values[0];
         const building = values[1];
         const uprns = values[2];
         const building_like = values[3];
-        if (is_building && typeof(building) === "undefined"){
+        if (is_building && typeof (building) === "undefined") {
             context.status = 404
         }
         data.user = user;
@@ -113,7 +113,7 @@ function frontendRoute(req, res) {
     });
 }
 
-function renderHTML(context, data, req, res){
+function renderHTML(context, data, req, res) {
     const markup = renderToString(
         <StaticRouter context={context} location={req.url}>
             <App user={data.user} building={data.building} building_like={data.building_like} />
@@ -124,7 +124,7 @@ function renderHTML(context, data, req, res){
         res.redirect(context.url);
     } else {
         res.status(context.status).send(
-`<!doctype html>
+            `<!doctype html>
     <html lang="">
     <head>
         <meta http-equiv="X-UA-Compatible" content="IE=edge" />
@@ -141,15 +141,15 @@ function renderHTML(context, data, req, res){
           }
         </style>
         ${
-          assets.client.css
-            ? `<link rel="stylesheet" href="${assets.client.css}">`
-            : ''
-        }
+            assets.client.css
+                ? `<link rel="stylesheet" href="${assets.client.css}">`
+                : ''
+            }
         ${
-          process.env.NODE_ENV === 'production'
-            ? `<script src="${assets.client.js}" defer></script>`
-            : `<script src="${assets.client.js}" defer crossorigin></script>`
-        }
+            process.env.NODE_ENV === 'production'
+                ? `<script src="${assets.client.js}" defer></script>`
+                : `<script src="${assets.client.js}" defer crossorigin></script>`
+            }
     </head>
     <body>
         <div id="root">${markup}</div>
@@ -169,24 +169,24 @@ server.use('/tiles', tileserver);
 // not implemented - may be useful to GET all buildings, paginated
 
 // GET buildings at point
-server.get('/buildings/locate', function(req, res){
+server.get('/buildings/locate', function (req, res) {
     const { lng, lat } = req.query;
-    queryBuildingsAtPoint(lng, lat).then(function(result){
+    queryBuildingsAtPoint(lng, lat).then(function (result) {
         res.send(result);
-    }).catch(function(error){
+    }).catch(function (error) {
         console.error(error);
-        res.send({error:'Database error'})
+        res.send({ error: 'Database error' })
     })
 });
 
 // GET buildings by reference (UPRN/TOID or other identifier)
-server.get('/buildings/reference', function(req, res){
+server.get('/buildings/reference', function (req, res) {
     const { key, id } = req.query;
-    queryBuildingsByReference(key, id).then(function(result){
+    queryBuildingsByReference(key, id).then(function (result) {
         res.send(result);
-    }).catch(function(error){
+    }).catch(function (error) {
         console.error(error);
-        res.send({error:'Database error'})
+        res.send({ error: 'Database error' })
     })
 });
 
@@ -194,31 +194,31 @@ server.get('/buildings/reference', function(req, res){
 server.route('/building/:building_id.json')
     .get(function (req, res) {
         const { building_id } = req.params;
-        getBuildingById(building_id).then(function(result){
+        getBuildingById(building_id).then(function (result) {
             res.send(result);
-        }).catch(function(error){
+        }).catch(function (error) {
             console.error(error);
-            res.send({error:'Database error'})
+            res.send({ error: 'Database error' })
         })
     })
     .post(function (req, res) {
         if (req.session.user_id) {
             updateBuilding(req, res, req.session.user_id);
-        }  else if (req.query.api_key) {
+        } else if (req.query.api_key) {
             authAPIUser(req.query.api_key)
-                .then(function(user){
+                .then(function (user) {
                     updateBuilding(req, res, user.user_id)
                 })
-                .catch(function(err){
+                .catch(function (err) {
                     console.error(err);
-                    res.send({error: 'Must be logged in'});
+                    res.send({ error: 'Must be logged in' });
                 });
         } else {
-            res.send({error: 'Must be logged in'});
+            res.send({ error: 'Must be logged in' });
         }
     })
 
-function updateBuilding(req, res, user_id){
+function updateBuilding(req, res, user_id) {
     const { building_id } = req.params;
     const building = req.body;
     saveBuilding(building_id, building, user_id).then(building => {
@@ -226,72 +226,72 @@ function updateBuilding(req, res, user_id){
             res.send(building)
             return
         }
-        if (typeof(building) === "undefined") {
-            res.send({error:'Database error'})
+        if (typeof (building) === "undefined") {
+            res.send({ error: 'Database error' })
             return
         }
         res.send(building)
     }).catch(
-        () => res.send({error:'Database error'})
+        () => res.send({ error: 'Database error' })
     )
 }
 
 // GET building UPRNs
 server.get('/building/:building_id/uprns.json', function (req, res) {
-        const { building_id } = req.params;
-        getBuildingUPRNsById(building_id).then(function(result){
-            if (typeof(result) === "undefined") {
-                res.send({error:'Database error'})
-                return
-            }
-            res.send({
-                uprns: result
-            });
-        }).catch(function(error){
-            console.error(error);
-            res.send({error:'Database error'})
-        })
+    const { building_id } = req.params;
+    getBuildingUPRNsById(building_id).then(function (result) {
+        if (typeof (result) === "undefined") {
+            res.send({ error: 'Database error' })
+            return
+        }
+        res.send({
+            uprns: result
+        });
+    }).catch(function (error) {
+        console.error(error);
+        res.send({ error: 'Database error' })
     })
+})
 
 // GET/POST like building
 server.route('/building/:building_id/like.json')
-    .get(function(req, res){
+    .get(function (req, res) {
         if (!req.session.user_id) {
-            res.send({like: false});  // not logged in, so cannot have liked
+            res.send({ like: false });  // not logged in, so cannot have liked
             return
         }
         const { building_id } = req.params;
         getBuildingLikeById(building_id, req.session.user_id).then(like => {
-            if (typeof(like) === "undefined") {
-                res.send({like: false})
+            if (typeof (like) === "undefined") {
+                res.send({ like: false })
                 return
             }
             // any value returned means like
-            res.send({like: true})
+            res.send({ like: true })
         }).catch(
-            () => res.send({error:'Database error'})
+            () => res.send({ error: 'Database error' })
         )
     })
-    .post(function(req, res){
+    .post(function (req, res) {
         if (!req.session.user_id) {
-            res.send({error: 'Must be logged in'});
+            res.send({ error: 'Must be logged in' });
             return
         }
         const { building_id } = req.params;
         const { like } = req.body;
-        if (like){
+        if (like) {
             likeBuilding(building_id, req.session.user_id).then(building => {
                 if (building.error) {
                     res.send(building)
                     return
                 }
-                if (typeof(building) === "undefined") {
-                    res.send({error:'Database error'})
+                if (typeof (building) === "undefined") {
+                    res.send({ error: 'Database error' })
                     return
                 }
                 res.send(building)
             }).catch(
-                () => res.send({error:'Database error'})
+                () => res.send({ error: 'Database error' })
             )
         } else {
             unlikeBuilding(building_id, req.session.user_id).then(building => {
@@ -299,113 +299,113 @@ server.route('/building/:building_id/like.json')
                     res.send(building)
                     return
                 }
-                if (typeof(building) === "undefined") {
-                    res.send({error:'Database error'})
+                if (typeof (building) === "undefined") {
+                    res.send({ error: 'Database error' })
                     return
                 }
                 res.send(building)
             }).catch(
-                () => res.send({error:'Database error'})
+                () => res.send({ error: 'Database error' })
             )
         }
     })
 
 // POST new user
-server.post('/users', function(req, res){
+server.post('/users', function (req, res) {
     const user = req.body;
     if (req.session.user_id) {
-        res.send({error: 'Already signed in'});
+        res.send({ error: 'Already signed in' });
         return
     }
 
-    if (user.email){
+    if (user.email) {
         if (user.email != user.confirm_email) {
-            res.send({error: "Email did not match confirmation."});
+            res.send({ error: "Email did not match confirmation." });
             return
         }
     } else {
         user.email = null;
     }
 
-    createUser(user).then(function(result){
+    createUser(user).then(function (result) {
         if (result.user_id) {
             req.session.user_id = result.user_id;
-            res.send({user_id: result.user_id});
+            res.send({ user_id: result.user_id });
         } else {
             req.session.user_id = undefined;
-            res.send({error: result.error});
+            res.send({ error: result.error });
         }
-    }).catch(function(err){
+    }).catch(function (err) {
         console.error(err);
         res.send(err)
     });
 });
 
 // POST user auth
-server.post('/login', function(req, res){
-    authUser(req.body.username, req.body.password).then(function(user) {
+server.post('/login', function (req, res) {
+    authUser(req.body.username, req.body.password).then(function (user) {
         if (user.user_id) {
             req.session.user_id = user.user_id;
         } else {
             req.session.user_id = undefined;
         }
         res.send(user);
-    }).catch(function(error){
+    }).catch(function (error) {
         res.send(error);
     })
 });
 
 // POST user logout
-server.post('/logout', function(req, res){
+server.post('/logout', function (req, res) {
     req.session.user_id = undefined;
-    req.session.destroy(function(err){
+    req.session.destroy(function (err) {
         if (err) {
             console.error(err);
-            res.send({error: 'Failed to end session'})
+            res.send({ error: 'Failed to end session' })
         }
-        res.send({success: true});
+        res.send({ success: true });
     });
 });
 
 // GET own user info
-server.get('/users/me', function(req, res){
+server.get('/users/me', function (req, res) {
     if (!req.session.user_id) {
-        res.send({error: 'Must be logged in'});
+        res.send({ error: 'Must be logged in' });
         return
     }
 
-    getUserById(req.session.user_id).then(function(user){
+    getUserById(req.session.user_id).then(function (user) {
         res.send(user);
-    }).catch(function(error){
+    }).catch(function (error) {
         res.send(error);
     });
 });
 
 // POST generate API key
-server.post('/api/key', function(req, res){
+server.post('/api/key', function (req, res) {
     if (!req.session.user_id) {
-        res.send({error: 'Must be logged in'});
+        res.send({ error: 'Must be logged in' });
         return
     }
 
-    getNewUserAPIKey(req.session.user_id).then(function(api_key){
+    getNewUserAPIKey(req.session.user_id).then(function (api_key) {
         res.send(api_key);
-    }).catch(function(error){
+    }).catch(function (error) {
         res.send(error);
     });
 })
 
 // GET search
-server.get('/search', function(req, res){
+server.get('/search', function (req, res) {
     const search_term = req.query.q;
-    if (!search_term){
+    if (!search_term) {
         res.send({
             error: 'Please provide a search term'
         })
         return
     }
     queryLocation(search_term).then((results) => {
-        if (typeof(results) === "undefined") {
+        if (typeof (results) === "undefined") {
             res.send({
                 error: 'Database error'
             })
@@ -425,7 +425,7 @@ server.get('/search', function(req, res){
                 }
             })
         })
-    }).catch(function(error){
+    }).catch(function (error) {
         res.send(error);
     });
 })
diff --git a/app/src/tiles/cache.js b/app/src/tiles/cache.js
index 5e4d0dea..4345e4c5 100644
--- a/app/src/tiles/cache.js
+++ b/app/src/tiles/cache.js
@@ -20,7 +20,7 @@ import fs from 'node-fs';
 
 const CACHE_PATH = process.env.TILECACHE_PATH
 
-function get(tileset, z, x, y, cb){
+function get(tileset, z, x, y, cb) {
     if (!should_try_cache(tileset, z)) {
         cb(`Skip cache get ${tileset}/${z}/${x}/${y}`, null)
         return
@@ -30,7 +30,7 @@ function get(tileset, z, x, y, cb){
     fs.readFile(fname, cb)
 }
 
-function put(im, tileset, z, x, y, cb){
+function put(im, tileset, z, x, y, cb) {
     if (!should_try_cache(tileset, z)) {
         cb(`Skip cache put ${tileset}/${z}/${x}/${y}`)
         return
@@ -40,7 +40,7 @@ function put(im, tileset, z, x, y, cb){
     fs.writeFile(fname, im, 'binary', (err) => {
         if (err && err.code === 'ENOENT') {
             fs.mkdir(dir, 0o755, true, (err) => {
-                if (err){
+                if (err) {
                     cb(err);
                 } else {
                     fs.writeFile(fname, im, 'binary', cb);
@@ -53,11 +53,11 @@ function put(im, tileset, z, x, y, cb){
 }
 
 function should_try_cache(tileset, z) {
-    if (tileset === 'date_year'){
+    if (tileset === 'date_year') {
         // cache high zoom because of front page hits
         return z <= 16
     }
-    if (tileset === 'base_light' ||  tileset === 'base_night') {
+    if (tileset === 'base_light' || tileset === 'base_night') {
         // cache for higher zoom levels (unlikely to change)
         return z <= 17
     }
diff --git a/app/src/tiles/tile.js b/app/src/tiles/tile.js
index ea41aa12..cca13a14 100644
--- a/app/src/tiles/tile.js
+++ b/app/src/tiles/tile.js
@@ -14,7 +14,7 @@ const DATASOURCE_CONFIG = {
     'password': process.env.PGPASSWORD,
     'port': process.env.PGPORT,
     'geometry_field': 'geometry_geom',
-    'extent' : '-20005048.4188,-9039211.13765,19907487.2779,17096598.5401',
+    'extent': '-20005048.4188,-9039211.13765,19907487.2779,17096598.5401',
     'srid': 3857,
     'type': 'postgis'
 }
@@ -129,26 +129,26 @@ const mercator = new SphericalMercator({
     size: TILE_SIZE
 });
 
-function get_bbox(z, x, y){
+function get_bbox(z, x, y) {
     return mercator.bbox(x, y, z, false, '900913');
 }
 
-function get_xyz(bbox, z){
+function get_xyz(bbox, z) {
     return mercator.xyz(bbox, z, false, '900913')
 }
 
-function render_tile(tileset, z, x, y, geometry_id, cb){
+function render_tile(tileset, z, x, y, geometry_id, cb) {
     const bbox = get_bbox(z, x, y)
 
     const map = new mapnik.Map(TILE_SIZE, TILE_SIZE, PROJ4_STRING);
     map.bufferSize = TILE_BUFFER_SIZE;
     const layer = new mapnik.Layer('tile', PROJ4_STRING);
 
-    const table_def = (tileset === 'highlight')?
+    const table_def = (tileset === 'highlight') ?
         get_highlight_table_def(geometry_id)
         : MAP_STYLE_TABLE_DEFINITIONS[tileset];
 
-    const conf = Object.assign({table: table_def}, DATASOURCE_CONFIG)
+    const conf = Object.assign({ table: table_def }, DATASOURCE_CONFIG)
 
     var postgis;
     try {
@@ -159,7 +159,7 @@ function render_tile(tileset, z, x, y, geometry_id, cb){
         map.load(
             path.join(__dirname, '..', 'map_styles', 'polygon.xml'),
             { strict: true },
-            function(err, map){
+            function (err, map) {
                 if (err) throw err
 
                 map.add_layer(layer)
@@ -171,7 +171,7 @@ function render_tile(tileset, z, x, y, geometry_id, cb){
                 });
             }
         )
-    } catch(err) {
+    } catch (err) {
         console.error(err);
     }
 }
diff --git a/app/src/tiles/tileserver.js b/app/src/tiles/tileserver.js
index fe7f2ac9..21c08e72 100644
--- a/app/src/tiles/tileserver.js
+++ b/app/src/tiles/tileserver.js
@@ -48,17 +48,17 @@ function handle_tile_request(tileset, req, res) {
     const int_x = strictParseInt(x);
     const int_y = strictParseInt(y);
 
-    if (isNaN(int_x) || isNaN(int_y) || isNaN(int_z)){
+    if (isNaN(int_x) || isNaN(int_y) || isNaN(int_z)) {
         console.error("Missing x or y or z")
-        return {error:'Bad parameter'}
+        return { error: 'Bad parameter' }
     }
 
     load_tile(tileset, int_z, int_x, int_y).then((im) => {
-        res.writeHead(200, {'Content-Type': 'image/png'})
+        res.writeHead(200, { 'Content-Type': 'image/png' })
         res.end(im)
     }).catch((err) => {
         console.error(err)
-        res.status(500).send({error: err})
+        res.status(500).send({ error: err })
     })
 }
 
@@ -158,8 +158,8 @@ function stitch_tile(tileset, z, x, y) {
             ).png().toBuffer()
         }).then((buf) => {
             return sharp(buf
-                ).resize(256, 256, {fit: 'inside'}
-                ).png().toBuffer()
+            ).resize(256, 256, { fit: 'inside' }
+            ).png().toBuffer()
         })
     });
 }
@@ -171,23 +171,23 @@ function handle_highlight_tile_request(req, res) {
     const int_x = strictParseInt(x);
     const int_y = strictParseInt(y);
 
-    if (isNaN(int_x) || isNaN(int_y) || isNaN(int_z)){
+    if (isNaN(int_x) || isNaN(int_y) || isNaN(int_z)) {
         console.error("Missing x or y or z")
-        return {error:'Bad parameter'}
+        return { error: 'Bad parameter' }
     }
 
     // highlight layer uses geometry_id to outline a single building
     const { highlight } = req.query
     const geometry_id = strictParseInt(highlight);
-    if(isNaN(geometry_id)){
-        res.status(400).send({error:'Bad parameter'})
+    if (isNaN(geometry_id)) {
+        res.status(400).send({ error: 'Bad parameter' })
         return
     }
 
-    render_tile('highlight', int_z, int_x, int_y, geometry_id, function(err, im) {
+    render_tile('highlight', int_z, int_x, int_y, geometry_id, function (err, im) {
         if (err) throw err
 
-        res.writeHead(200, {'Content-Type': 'image/png'})
+        res.writeHead(200, { 'Content-Type': 'image/png' })
         res.end(im)
     })
 }