diff --git a/services/web/app/src/Features/Project/ProjectHistoryHandler.js b/services/web/app/src/Features/Project/ProjectHistoryHandler.js
index 3c16a2eb11..26a9a9771b 100644
--- a/services/web/app/src/Features/Project/ProjectHistoryHandler.js
+++ b/services/web/app/src/Features/Project/ProjectHistoryHandler.js
@@ -1,190 +1,147 @@
-/* eslint-disable
-    camelcase,
-    n/handle-callback-err,
-    max-len,
-    no-unused-vars,
-*/
-// TODO: This file was created by bulk-decaffeinate.
-// Fix any style issues and re-enable lint.
-/*
- * decaffeinate suggestions:
- * DS102: Remove unnecessary code created because of implicit returns
- * DS207: Consider shorter variations of null checks
- * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
- */
 const { Project } = require('../../models/Project')
 const ProjectDetailsHandler = require('./ProjectDetailsHandler')
-const logger = require('@overleaf/logger')
-const settings = require('@overleaf/settings')
 const HistoryManager = require('../History/HistoryManager')
 const ProjectEntityUpdateHandler = require('./ProjectEntityUpdateHandler')
 const { promisifyAll } = require('../../util/promises')
 
 const ProjectHistoryHandler = {
-  setHistoryId(project_id, history_id, callback) {
+  setHistoryId(projectId, historyId, callback) {
     // reject invalid history ids
-    if (callback == null) {
-      callback = function () {}
-    }
-    if (history_id == null) {
+    if (historyId == null) {
       return callback(new Error('missing history id'))
     }
     // use $exists:false to prevent overwriting any existing history id, atomically
-    return Project.updateOne(
-      { _id: project_id, 'overleaf.history.id': { $exists: false } },
-      { 'overleaf.history.id': history_id },
+    Project.updateOne(
+      { _id: projectId, 'overleaf.history.id': { $exists: false } },
+      { 'overleaf.history.id': historyId },
       function (err, result) {
-        if (err != null) {
+        if (err) {
           return callback(err)
         }
-        if ((result != null ? result.n : undefined) === 0) {
+        if (result.n === 0) {
           return callback(new Error('history exists'))
         }
-        return callback()
+        callback()
       }
     )
   },
 
-  getHistoryId(project_id, callback) {
-    if (callback == null) {
-      callback = function () {}
-    }
-    return ProjectDetailsHandler.getDetails(
-      project_id,
-      function (err, project) {
-        if (err != null) {
-          return callback(err)
-        } // n.b. getDetails returns an error if the project doesn't exist
-        return callback(null, project?.overleaf?.history?.id)
-      }
-    )
+  getHistoryId(projectId, callback) {
+    ProjectDetailsHandler.getDetails(projectId, function (err, project) {
+      if (err) {
+        return callback(err)
+      } // n.b. getDetails returns an error if the project doesn't exist
+      callback(null, project?.overleaf?.history?.id)
+    })
   },
 
-  unsetHistory(project_id, callback) {
-    return Project.updateOne(
-      { _id: project_id },
+  unsetHistory(projectId, callback) {
+    Project.updateOne(
+      { _id: projectId },
       { $unset: { 'overleaf.history': true } },
       callback
     )
   },
 
-  upgradeHistory(project_id, allowDowngrade, callback) {
+  upgradeHistory(projectId, allowDowngrade, callback) {
     // project must have an overleaf.history.id before allowing display of new history
-    if (callback == null) {
-      callback = function () {}
-    }
-    return Project.updateOne(
-      { _id: project_id, 'overleaf.history.id': { $exists: true } },
+    Project.updateOne(
+      { _id: projectId, 'overleaf.history.id': { $exists: true } },
       {
         'overleaf.history.display': true,
         'overleaf.history.upgradedAt': new Date(),
         'overleaf.history.allowDowngrade': allowDowngrade,
       },
       function (err, result) {
-        if (err != null) {
+        if (err) {
           return callback(err)
         }
         // return an error if overleaf.history.id wasn't present
-        if ((result != null ? result.n : undefined) === 0) {
+        if (result.n === 0) {
           return callback(new Error('history not upgraded'))
         }
-        return callback()
+        callback()
       }
     )
   },
 
-  downgradeHistory(project_id, callback) {
-    if (callback == null) {
-      callback = function () {}
-    }
-    return Project.updateOne(
-      { _id: project_id, 'overleaf.history.upgradedAt': { $exists: true } },
+  downgradeHistory(projectId, callback) {
+    Project.updateOne(
+      { _id: projectId, 'overleaf.history.upgradedAt': { $exists: true } },
       {
         'overleaf.history.display': false,
         $unset: { 'overleaf.history.upgradedAt': 1 },
       },
       function (err, result) {
-        if (err != null) {
+        if (err) {
           return callback(err)
         }
-        if ((result != null ? result.n : undefined) === 0) {
+        if (result.n === 0) {
           return callback(new Error('history not downgraded'))
         }
-        return callback()
+        callback()
       }
     )
   },
 
-  setMigrationArchiveFlag(project_id, callback) {
-    if (callback == null) {
-      callback = function () {}
-    }
+  setMigrationArchiveFlag(projectId, callback) {
     Project.updateOne(
-      { _id: project_id, version: { $exists: true } },
+      { _id: projectId, version: { $exists: true } },
       {
         'overleaf.history.zipFileArchivedInProject': true,
       },
       function (err, result) {
-        if (err != null) {
+        if (err) {
           return callback(err)
         }
-        if ((result != null ? result.n : undefined) === 0) {
+        if (result.n === 0) {
           return callback(new Error('migration flag not set'))
         }
-        return callback()
+        callback()
       }
     )
   },
 
-  ensureHistoryExistsForProject(project_id, callback) {
+  ensureHistoryExistsForProject(projectId, callback) {
     // We can only set a history id for a project that doesn't have one. The
     // history id is cached in the project history service, and changing an
     // existing value corrupts the history, leaving it in an irrecoverable
     // state. Setting a history id when one wasn't present before is ok,
     // because undefined history ids aren't cached.
-    if (callback == null) {
-      callback = function () {}
-    }
-    return ProjectHistoryHandler.getHistoryId(
-      project_id,
-      function (err, history_id) {
-        if (err != null) {
+    ProjectHistoryHandler.getHistoryId(projectId, function (err, historyId) {
+      if (err) {
+        return callback(err)
+      }
+      if (historyId != null) {
+        return callback()
+      } // history already exists, success
+      HistoryManager.initializeProject(projectId, function (err, historyId) {
+        if (err) {
           return callback(err)
         }
-        if (history_id != null) {
-          return callback()
-        } // history already exists, success
-        return HistoryManager.initializeProject(
-          project_id,
-          function (err, historyId) {
-            if (err != null) {
+        if (historyId == null) {
+          return callback(new Error('failed to initialize history id'))
+        }
+        ProjectHistoryHandler.setHistoryId(
+          projectId,
+          historyId,
+          function (err) {
+            if (err) {
               return callback(err)
             }
-            if (historyId == null) {
-              return callback(new Error('failed to initialize history id'))
-            }
-            return ProjectHistoryHandler.setHistoryId(
-              project_id,
-              historyId,
+            ProjectEntityUpdateHandler.resyncProjectHistory(
+              projectId,
               function (err) {
-                if (err != null) {
+                if (err) {
                   return callback(err)
                 }
-                return ProjectEntityUpdateHandler.resyncProjectHistory(
-                  project_id,
-                  function (err) {
-                    if (err != null) {
-                      return callback(err)
-                    }
-                    return HistoryManager.flushProject(project_id, callback)
-                  }
-                )
+                HistoryManager.flushProject(projectId, callback)
               }
             )
           }
         )
-      }
-    )
+      })
+    })
   },
 }