diff --git a/common/models/user.js b/common/models/user.js
index 9f82a86ea3..cc81e01fa9 100644
--- a/common/models/user.js
+++ b/common/models/user.js
@@ -52,6 +52,12 @@ module.exports = function(User) {
   User.validatesUniquenessOf('username');
   User.settings.emailVerificationRequired = false;
 
+  User.on('dataSourceAttached', () => {
+    User.findOne$ = Observable.fromNodeCallback(User.findOne, User);
+    User.update$ = Observable.fromNodeCallback(User.updateAll, User);
+    User.count$ = Observable.fromNodeCallback(User.count, User);
+  });
+
   User.observe('before save', function({ instance: user }, next) {
     if (user) {
       user.username = user.username.trim().toLowerCase();
@@ -416,4 +422,21 @@ module.exports = function(User) {
       }
     }
   );
+
+  // user.updateTo$(updateData: Object) => Observable[Number]
+  User.prototype.update$ = function update$(updateData) {
+    const id = this.getId();
+    const updateOptions = { allowExtendedOperators: true };
+    if (
+        !updateData ||
+        typeof updateData !== 'object' ||
+        Object.keys(updateData).length > 0
+    ) {
+      return Observable.throw(new Error(
+        `updateData must be an object with at least on key,
+        but got ${updateData}`.split('\n').join(' ')
+      ));
+    }
+    return this.constructor.update$({ id }, updateData, updateOptions);
+  };
 };
diff --git a/server/boot/challenge.js b/server/boot/challenge.js
index 70c0534969..1f7fda0d4d 100644
--- a/server/boot/challenge.js
+++ b/server/boot/challenge.js
@@ -2,7 +2,7 @@ import _ from 'lodash';
 import dedent from 'dedent';
 import moment from 'moment';
 import { Observable, Scheduler } from 'rx';
-import debugFactory from 'debug';
+import debug from 'debug';
 import accepts from 'accepts';
 
 import {
@@ -14,7 +14,7 @@ import {
   randomCompliment
 } from '../utils';
 
-import { saveUser, observeMethod } from '../utils/rx';
+import { observeMethod } from '../utils/rx';
 
 import {
   ifNoUserSend
@@ -24,7 +24,7 @@ import getFromDisk$ from '../utils/getFromDisk$';
 
 const isDev = process.env.NODE_ENV !== 'production';
 const isBeta = !!process.env.BETA;
-const debug = debugFactory('freecc:challenges');
+const log = debug('freecc:challenges');
 const challengesRegex = /^(bonfire|waypoint|zipline|basejump|checkpoint)/i;
 const challengeView = {
   0: 'challenges/showHTML',
@@ -40,8 +40,7 @@ function isChallengeCompleted(user, challengeId) {
   if (!user) {
     return false;
   }
-  return user.completedChallenges.some(challenge =>
-    challenge.id === challengeId );
+  return user.challengeMap[challengeId];
 }
 
 /*
@@ -50,36 +49,53 @@ function numberWithCommas(x) {
 }
 */
 
-function updateUserProgress(user, challengeId, completedChallenge) {
-  let { completedChallenges } = user;
+function buildUserUpdate(
+  user,
+  challengeId,
+  completedChallenge,
+  timezone
+) {
+  const updateData = { $set: {} };
+  let finalChallenge;
+  const { timezone: userTimezone, challengeMap = {} } = user;
 
-  const indexOfChallenge = _.findIndex(completedChallenges, {
-    id: challengeId
-  });
+  const oldChallenge = challengeMap[challengeId];
+  const alreadyCompleted = !!oldChallenge;
 
-  const alreadyCompleted = indexOfChallenge !== -1;
 
-  if (!alreadyCompleted) {
-    user.progressTimestamps.push({
+  if (alreadyCompleted) {
+    // add data from old challenge
+    finalChallenge = {
+      ...completedChallenge,
+      completedDate: oldChallenge.completedDate,
+      lastUpdated: completedChallenge.completedDate
+    };
+
+    updateData.$push = {
       timestamp: Date.now(),
       completedChallenge: challengeId
-    });
-    user.completedChallenges.push(completedChallenge);
-    return user;
+    };
+  } else {
+    finalChallenge = completedChallenge;
   }
 
-  const oldCompletedChallenge = completedChallenges[indexOfChallenge];
-  user.completedChallenges[indexOfChallenge] =
-    Object.assign(
-      {},
-      completedChallenge,
-      {
-        completedDate: oldCompletedChallenge.completedDate,
-        lastUpdated: completedChallenge.completedDate
-      }
-    );
+  updateData.$set = {
+    [`challengeMap.${challengeId}`]: finalChallenge
+  };
 
-  return { user, alreadyCompleted };
+  if (
+    timezone !== 'UTC' &&
+    (!userTimezone || userTimezone === 'UTC')
+  ) {
+    updateData.$set = {
+      ...updateData.$set,
+      timezone: userTimezone
+    };
+  }
+
+  log('user update data', updateData);
+
+  return { alreadyCompleted, updateData };
 }
 
 
@@ -117,7 +133,7 @@ function getRenderData$(user, challenge$, origChallengeName, solution) {
     .replace(challengesRegex, '');
 
   const testChallengeName = new RegExp(challengeName, 'i');
-  debug('looking for %s', testChallengeName);
+  log('looking for %s', testChallengeName);
 
   return challenge$
     .map(challenge => challenge.toJSON())
@@ -136,7 +152,7 @@ function getRenderData$(user, challenge$, origChallengeName, solution) {
 
       // Handle not found
       if (!challenge) {
-        debug('did not find challenge for ' + origChallengeName);
+        log('did not find challenge for ' + origChallengeName);
         return Observable.just({
           type: 'redirect',
           redirectUrl: '/map',
@@ -187,25 +203,21 @@ function getRenderData$(user, challenge$, origChallengeName, solution) {
     });
 }
 
-function getCompletedChallengeIds(user = {}) {
-  // if user
-  // get the id's of all the users completed challenges
-  return !user.completedChallenges ?
-    [] :
-    _.uniq(user.completedChallenges)
-      .map(({ id, _id }) => id || _id);
-}
-
 // create a stream of an array of all the challenge blocks
-function getSuperBlocks$(challenge$, completedChallenges) {
+function getSuperBlocks$(challenge$, challengeMap) {
   return challenge$
     // mark challenge completed
     .map(challengeModel => {
       const challenge = challengeModel.toJSON();
-      if (completedChallenges.indexOf(challenge.id) !== -1) {
-        challenge.completed = true;
-      }
+      challenge.completed = !!challengeMap[challenge.id];
       challenge.markNew = shouldShowNew(challenge);
+
+      if (challenge.type === 'hike') {
+        challenge.url = '/videos/' + challenge.dashedName;
+      } else {
+        challenge.url = '/challenges/' + challenge.dashedName;
+      }
+
       return challenge;
     })
     // group challenges by block | returns a stream of observables
@@ -223,15 +235,6 @@ function getSuperBlocks$(challenge$, completedChallenges) {
       const isComingSoon = _.every(blockArray, 'isComingSoon');
       const isRequired = _.every(blockArray, 'isRequired');
 
-      blockArray = blockArray.map(challenge => {
-        if (challenge.challengeType == 6 && challenge.type === 'hike') {
-          challenge.url = '/videos/' + challenge.dashedName;
-        } else {
-          challenge.url = '/challenges/' + challenge.dashedName;
-        }
-        return challenge;
-      });
-
       return {
         isBeta,
         isComingSoon,
@@ -428,7 +431,7 @@ module.exports = function(app) {
     getChallengeById$(challenge$, challengeId)
       .doOnNext(({ dashedName })=> {
         if (!dashedName) {
-          debug('no challenge found for %s', challengeId);
+          log('no challenge found for %s', challengeId);
           req.flash('info', {
             msg: `We coudn't find a challenge with the id ${challengeId}`
           });
@@ -473,7 +476,7 @@ module.exports = function(app) {
         return getNextChallenge$(challenge$, blocks$, challengeId)
           .doOnNext(({ dashedName } = {}) => {
             if (!dashedName) {
-              debug('no challenge found for %s', challengeId);
+              log('no challenge found for %s', challengeId);
               res.redirect('/map');
             }
             res.redirect('/challenges/' + dashedName);
@@ -495,7 +498,7 @@ module.exports = function(app) {
             });
           }
           if (type === 'redirect') {
-            debug('redirecting to %s', redirectUrl);
+            log('redirecting to %s', redirectUrl);
             return res.redirect(redirectUrl);
           }
           var view = challengeView[data.challengeType];
@@ -521,7 +524,7 @@ module.exports = function(app) {
       timezone
     } = req.body;
 
-    const { alreadyCompleted } = updateUserProgress(
+    const { alreadyCompleted, updateData } = buildUserUpdate(
       req.user,
       id,
       {
@@ -529,20 +532,16 @@ module.exports = function(app) {
         challengeType,
         solution,
         name,
-        completedDate,
-        verified: true
-      }
+        completedDate
+      },
+      timezone
     );
 
-    if (timezone && (!req.user.timezone || req.user.timezone !== timezone)) {
-      req.user.timezone = timezone;
-    }
-
-    let user = req.user;
-    saveUser(req.user)
+    const user = req.user;
+    return user.updateTo$(updateData)
+      .doOnNext(count => log('%s documents updated', count))
       .subscribe(
-        function(user) {
-          user = user;
+        function() {
         },
         next,
         function() {
@@ -558,7 +557,7 @@ module.exports = function(app) {
   }
 
   function completedZiplineOrBasejump(req, res, next) {
-    const { body = {} } = req;
+    const { user, body = {} } = req;
 
     let completedChallenge;
     // backwards compatibility
@@ -606,16 +605,19 @@ module.exports = function(app) {
     }
 
 
-    updateUserProgress(req.user, completedChallenge.id, completedChallenge);
+    const {
+      updateData
+    } = buildUserUpdate(req.user, completedChallenge.id, completedChallenge);
 
-    return saveUser(req.user)
+    return user.updateTo$(updateData)
       .doOnNext(() => res.status(200).send(true))
       .subscribe(() => {}, next);
   }
 
-  function showMap(showAside, { user }, res, next) {
+  function showMap(showAside, { user = {} }, res, next) {
+    const { challengeMap = {} } = user;
 
-    getSuperBlocks$(challenge$, getCompletedChallengeIds(user))
+    return getSuperBlocks$(challenge$, challengeMap)
       .subscribe(
         superBlocks => {
           res.render('map/show', {
diff --git a/server/boot/user.js b/server/boot/user.js
index 1b1eddc3ea..48e7cad301 100644
--- a/server/boot/user.js
+++ b/server/boot/user.js
@@ -1,4 +1,3 @@
-import _ from 'lodash';
 import dedent from 'dedent';
 import moment from 'moment-timezone';
 import { Observable } from 'rx';
@@ -60,6 +59,61 @@ function encodeFcc(value = '') {
   return replaceScriptTags(replaceFormAction(value));
 }
 
+function isAlgorithm(challenge) {
+  // test if name starts with hike/waypoint/basejump/zipline
+  // fix for bug that saved different challenges with incorrect
+  // challenge types
+  return !(/^(waypoint|hike|zipline|basejump)/i).test(challenge.name) &&
+    +challenge.challengeType === 5;
+}
+
+function isProject(challenge) {
+  return +challenge.challengeType === 3 ||
+    +challenge.challengeType === 4;
+}
+
+function getChallengeGroup(challenge) {
+  if (isProject(challenge)) {
+    return 'projects';
+  } else if (isAlgorithm(challenge)) {
+    return 'algorithms';
+  }
+  return 'challenges';
+}
+
+// buildDisplayChallenges(challengeMap: Object, tz: String) => Observable[{
+//   algorithms: Array,
+//   projects: Array,
+//   challenges: Array
+// }]
+function buildDisplayChallenges(challengeMap = {}, timezone) {
+  return Observable.from(Object.keys(challengeMap))
+    .map(challengeId => challengeMap[challengeId])
+    .map(challenge => {
+      let finalChallenge = { ...challenge };
+      if (challenge.completedDate) {
+        finalChallenge.completedDate = moment
+          .tz(challenge.completedDate, timezone)
+          .format(dateFormat);
+      }
+
+      if (challenge.lastUpdated) {
+        finalChallenge.lastUpdated = moment
+          .tz(challenge.lastUpdated, timezone)
+          .format(dateFormat);
+      }
+
+      return finalChallenge;
+    })
+    .groupBy(getChallengeGroup)
+    .flatMap(group$ => {
+      return group$.toArray().map(challenges => ({
+        [getChallengeGroup(challenges[0])]: challenges
+      }));
+    })
+    .reduce((output, group) => ({ ...output, ...group}), {});
+}
+
 module.exports = function(app) {
   var router = app.loopback.Router();
   var User = app.models.User;
@@ -170,33 +224,35 @@ module.exports = function(app) {
 
   function returnUser(req, res, next) {
     const username = req.params.username.toLowerCase();
-    const { path } = req;
-    User.findOne(
-      {
-        where: { username },
-        include: 'pledge'
-      },
-      function(err, profileUser) {
-        if (err) {
-          return next(err);
-        }
-        if (!profileUser) {
+    const { user, path } = req;
+
+    // timezone of signed-in account
+    // to show all date related components
+    // using signed-in account's timezone
+    // not of the profile she is viewing
+    const timezone = user && user.timezone ?
+      user.timezone :
+      'UTC';
+
+    const query = {
+      where: { username },
+      include: 'pledge'
+    };
+
+    return User.findOne$(query)
+      .filter(userPortfolio => {
+        if (!userPortfolio) {
           req.flash('errors', {
-            msg: `404: We couldn't find path ${ path }`
+            msg: `We couldn't find a page for ${ path }`
           });
-          console.log('404');
-          return res.redirect('/');
+          res.redirect('/');
         }
-        profileUser = profileUser.toJSON();
+        return !!userPortfolio;
+      })
+      .flatMap(userPortfolio => {
+        userPortfolio = userPortfolio.toJSON();
 
-        // timezone of signed-in account
-        // to show all date related components
-        // using signed-in account's timezone
-        // not of the profile she is viewing
-        const timezone = req.user &&
-          req.user.timezone ? req.user.timezone : 'UTC';
-
-        const timestamps = profileUser
+        const timestamps = userPortfolio
           .progressTimestamps
           .map(objOrNum => {
             return typeof objOrNum === 'number' ?
@@ -206,10 +262,10 @@ module.exports = function(app) {
 
         const uniqueDays = prepUniqueDays(timestamps, timezone);
 
-        profileUser.currentStreak = calcCurrentStreak(uniqueDays, timezone);
-        profileUser.longestStreak = calcLongestStreak(uniqueDays, timezone);
+        userPortfolio.currentStreak = calcCurrentStreak(uniqueDays, timezone);
+        userPortfolio.longestStreak = calcLongestStreak(uniqueDays, timezone);
 
-        const data = profileUser
+        const calender = userPortfolio
           .progressTimestamps
           .map((objOrNum) => {
             return typeof objOrNum === 'number' ?
@@ -224,89 +280,30 @@ module.exports = function(app) {
             return data;
           }, {});
 
-        function filterAlgos(challenge) {
-          // test if name starts with hike/waypoint/basejump/zipline
-          // fix for bug that saved different challenges with incorrect
-          // challenge types
-          return !(/^(waypoint|hike|zipline|basejump)/i).test(challenge.name) &&
-            +challenge.challengeType === 5;
-        }
-
-        function filterProjects(challenge) {
-          return +challenge.challengeType === 3 ||
-            +challenge.challengeType === 4;
-        }
-
-        const completedChallenges = profileUser.completedChallenges
-          .filter(({ name }) => typeof name === 'string')
-          .map(challenge => {
-              challenge = { ...challenge };
-              if (challenge.completedDate) {
-                challenge.completedDate =
-                  moment.tz(challenge.completedDate, timezone)
-                    .format(dateFormat);
-              }
-              if (challenge.lastUpdated) {
-                challenge.lastUpdated =
-                  moment.tz(challenge.lastUpdated, timezone).format(dateFormat);
-              }
-              return challenge;
-          });
-
-        const projects = completedChallenges.filter(filterProjects);
-
-        const algos = completedChallenges.filter(filterAlgos);
-
-        const challenges = completedChallenges
-          .filter(challenge => !filterAlgos(challenge))
-          .filter(challenge => !filterProjects(challenge));
-
-        res.render('account/show', {
-          title: 'Camper ' + profileUser.username + '\'s Code Portfolio',
-          username: profileUser.username,
-          name: profileUser.name,
-
-          isMigrationGrandfathered: profileUser.isMigrationGrandfathered,
-          isGithubCool: profileUser.isGithubCool,
-          isLocked: !!profileUser.isLocked,
-
-          pledge: profileUser.pledge,
-
-          isFrontEndCert: profileUser.isFrontEndCert,
-          isDataVisCert: profileUser.isDataVisCert,
-          isBackEndCert: profileUser.isBackEndCert,
-          isFullStackCert: profileUser.isFullStackCert,
-          isHonest: profileUser.isHonest,
-
-          location: profileUser.location,
-          calender: data,
-
-          github: profileUser.githubURL,
-          linkedin: profileUser.linkedin,
-          google: profileUser.google,
-          facebook: profileUser.facebook,
-          twitter: profileUser.twitter,
-          picture: profileUser.picture,
-
-          progressTimestamps: profileUser.progressTimestamps,
-
-          projects,
-          algos,
-          challenges,
-          moment,
-
-          longestStreak: profileUser.longestStreak,
-          currentStreak: profileUser.currentStreak,
-
-          encodeFcc
-        });
-      }
-    );
+        return buildDisplayChallenges(userPortfolio.challengeMap, timezone)
+          .map(displayChallenges => ({
+            ...userPortfolio,
+            ...displayChallenges,
+            title: 'Camper ' + userPortfolio.username + '\'s Code Portfolio',
+            calender,
+            github: userPortfolio.githubURL,
+            moment,
+            encodeFcc
+          }));
+      })
+      .doOnNext(data => {
+        return res.render('account/show', data);
+      })
+      .subscribe(
+        () => {},
+        next
+      );
   }
 
   function showCert(certType, req, res, next) {
     const username = req.params.username.toLowerCase();
     const { user } = req;
+    const certId = certIds[certType];
     Observable.just(user)
       .flatMap(user => {
         if (user && user.username === username) {
@@ -321,9 +318,9 @@ module.exports = function(app) {
           isBackEndCert: true,
           isFullStackCert: true,
           isHonest: true,
-          completedChallenges: true,
           username: true,
-          name: true
+          name: true,
+          [ `challengesMap.${certId}` ]: true
         });
       })
       .subscribe(
@@ -376,15 +373,8 @@ module.exports = function(app) {
 
           if (user[certType]) {
 
-            // find challenge in user profile
-            // if not found supply empty object
-            // if found grab date
-            // if no date use todays date
-            var { completedDate = new Date() } =
-              _.find(
-                user.completedChallenges,
-                { id: certIds[certType] }
-            ) || {};
+            const { completedDate = new Date() } =
+              user.challengeMap[certId] || {};
 
             return res.render(
               certViews[certType],
@@ -511,29 +501,6 @@ module.exports = function(app) {
     });
   }
 
-  /*
-  function updateUserStoryPictures(userId, picture, username, cb) {
-    Story.find({ 'author.userId': userId }, function(err, stories) {
-      if (err) { return cb(err); }
-
-      const tasks = [];
-      stories.forEach(function(story) {
-        story.author.picture = picture;
-        story.author.username = username;
-        tasks.push(function(cb) {
-          story.save(cb);
-        });
-      });
-      async.parallel(tasks, function(err) {
-        if (err) {
-          return cb(err);
-        }
-        cb();
-      });
-    });
-  }
-  */
-
   function vote1(req, res, next) {
     if (req.user) {
       req.user.tshirtVote = 1;
diff --git a/server/views/account/show.jade b/server/views/account/show.jade
index c5f48513f6..8d3e4bc576 100644
--- a/server/views/account/show.jade
+++ b/server/views/account/show.jade
@@ -140,7 +140,7 @@ block content
                                       a(href=challenge.solution, target='_blank') View my project
                                   td.col-xs-12.visible-xs
                                       a(href=challenge.solution, target='_blank')= removeOldTerms(challenge.name)
-              if (algos.length > 0)
+              if (algorithms.length > 0)
                   .col-sm-12
                       table.table.table-striped
                           thead
@@ -149,7 +149,7 @@ block content
                                   th.col-xs-2.hidden-xs Completed
                                   th.col-xs-2.hidden-xs Last Updated
                                   th.col-xs-2.hidden-xs Solution
-                          for challenge in algos
+                          for challenge in algorithms
                               tr
                                   td.col-xs-5.hidden-xs= removeOldTerms(challenge.name)
                                   td.col-xs-2.hidden-xs= challenge.completedDate ? challenge.completedDate : 'Not Available'