diff --git a/composer.json b/composer.json
index e8c468995a9..d538484a417 100644
--- a/composer.json
+++ b/composer.json
@@ -20,7 +20,8 @@
         "php-webdriver/webdriver" : "^1.8.2",
         "phan/phan": ">=2.3.0",
         "phpmd/phpmd": "~2.8",
-        "phpstan/phpstan": "0.12.17"
+        "phpstan/phpstan": "0.12.17",
+        "slevomat/coding-standard": "^6.0"
     },
     "scripts": {
       "pre-install-cmd": "mkdir -p project/libraries"
diff --git a/composer.lock b/composer.lock
index 3fe5236a596..1d41ccdd7b0 100644
--- a/composer.lock
+++ b/composer.lock
@@ -3706,6 +3706,47 @@
             "homepage": "https://github.com/sebastianbergmann/version",
             "time": "2016-10-03T07:35:21+00:00"
         },
+        {
+            "name": "slevomat/coding-standard",
+            "version": "6.1.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/slevomat/coding-standard.git",
+                "reference": "0a7934d7ecdfe402079027513daa3b7e881f315d"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/slevomat/coding-standard/zipball/0a7934d7ecdfe402079027513daa3b7e881f315d",
+                "reference": "0a7934d7ecdfe402079027513daa3b7e881f315d",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.1",
+                "phpstan/phpdoc-parser": "0.3.5 - 0.4.2",
+                "squizlabs/php_codesniffer": "^3.5.3"
+            },
+            "require-dev": {
+                "dealerdirect/phpcodesniffer-composer-installer": "0.5.0",
+                "jakub-onderka/php-parallel-lint": "1.0.0",
+                "phing/phing": "2.16.2",
+                "phpstan/phpstan": "0.11.19|0.12.5",
+                "phpstan/phpstan-phpunit": "0.11.2|0.12.6",
+                "phpstan/phpstan-strict-rules": "0.11.1|0.12.1",
+                "phpunit/phpunit": "7.5.18|8.5.2"
+            },
+            "type": "phpcodesniffer-standard",
+            "autoload": {
+                "psr-4": {
+                    "SlevomatCodingStandard\\": "SlevomatCodingStandard"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "Slevomat Coding Standard for PHP_CodeSniffer complements Consistence Coding Standard by providing sniffs with additional checks.",
+            "time": "2020-01-23T15:37:30+00:00"
+        },
         {
             "name": "squizlabs/php_codesniffer",
             "version": "3.5.3",
diff --git a/php/libraries/Database.class.inc b/php/libraries/Database.class.inc
index aba643a0279..3d9d2b046ce 100644
--- a/php/libraries/Database.class.inc
+++ b/php/libraries/Database.class.inc
@@ -1,4 +1,5 @@
 <?php declare(strict_types=1);
+
 define("DEBUG", false);
 
 /**
@@ -56,13 +57,13 @@ class Database
      * NOTE There is no return type declaration for this function as it returns
      * the type `Database` which is not supported by PHPs built in return types.
      *
-     * @param string  $database     the database to select
-     * @param string  $username     the username with which to log into
-     *                              the database server
-     * @param string  $password     the password that matches the username
-     * @param string  $host         the name of the database server
-     * @param boolean $trackChanges boolean determining if changes should be
-     *                              logged to the history table
+     * @param string $database     the database to select
+     * @param string $username     the username with which to log into
+     *                             the database server
+     * @param string $password     the password that matches the username
+     * @param string $host         the name of the database server
+     * @param bool   $trackChanges boolean determining if changes should be
+     *                             logged to the history table
      *
      * @return \Database
      * @throws \DatabaseException
@@ -73,7 +74,7 @@ class Database
         string $username     = '',
         string $password     = '',
         string $host         = '',
-        bool   $trackChanges = true
+        bool $trackChanges = true
     ): \Database {
 
         static $connections = array();
@@ -126,19 +127,19 @@ class Database
      *                                  the database server
      * @param string|null $password     the password that matches the username
      * @param string|null $host         the name of the database server
-     * @param boolean     $trackChanges whether to use the trackChanges
+     * @param bool        $trackChanges whether to use the trackChanges
      *                                  mechanism on this connection
      *
      * @return bool True if DB connection established. False otherwise.
      * @access public
      */
     function connect(
-        $database,
+        string $database,
         ?string $username,
         ?string $password,
         ?string $host,
-        bool   $trackChanges = true
-    ) : bool {
+        bool $trackChanges = true
+    ): bool {
 
         $this->_trackChanges = $trackChanges;
         $this->_databaseName = $database;
@@ -219,7 +220,7 @@ class Database
     /**
      * Determines whether the database connection is alive
      *
-     * @return boolean
+     * @return bool
      * @access public
      */
     function isConnected(): bool
@@ -241,8 +242,8 @@ class Database
      * This will insert a row. HTML from any field in the row will be automatically
      * escaped to avoid injection.
      *
-     * @param string $table the table into which to insert the row
-     * @param array  $set   the values with which to fill the new row
+     * @param string               $table the table into which to insert the row
+     * @param array<string,string> $set   the values with which to fill the new row
      *
      * @return void
      */
@@ -258,8 +259,8 @@ class Database
      * automatically escaped. This should only be called when we know the source of
      * the input is trustworthy and must contain HTML.
      *
-     * @param string $table the table into which to insert the row
-     * @param array  $set   the values with which to fill the new row
+     * @param string               $table the table into which to insert the row
+     * @param array<string,string> $set   the values with which to fill the new row
      *
      * @return void
      */
@@ -274,8 +275,8 @@ class Database
      * This will insert a row. HTML from any field in the row will be automatically
      * escaped to avoid injection.
      *
-     * @param string $table the table into which to insert the row
-     * @param array  $set   the values with which to fill the new row
+     * @param string               $table the table into which to insert the row
+     * @param array<string,string> $set   the values with which to fill the new row
      *
      * @return void
      */
@@ -292,8 +293,8 @@ class Database
      * value for any unique key, the row where the duplicate is present will be
      * updated.
      *
-     * @param string $table the table into which to insert the row
-     * @param array  $set   the values with which to fill the row
+     * @param string               $table the table into which to insert the row
+     * @param array<string,string> $set   the values with which to fill the row
      *
      * @return bool
      */
@@ -310,8 +311,8 @@ class Database
      * value for any unique key, the row where the duplicate is present will be
      * updated. HTML from any field in the row will *not* be automatically escaped.
      *
-     * @param string $table the table into which to insert the row
-     * @param array  $set   the values with which to fill the row
+     * @param string               $table the table into which to insert the row
+     * @param array<string,string> $set   the values with which to fill the row
      *
      * @return bool
      */
@@ -332,9 +333,9 @@ class Database
      *
      * This function alone does not guarantee safety.
      *
-     * @param array $set The array to be inserted as a new row
+     * @param array<string,string> $set The array to be inserted as a new row
      *
-     * @return array A copy of $set with the HTML characters escaped
+     * @return array<string,string> A copy of $set with the HTML characters escaped
      */
     private function _HTMLEscapeArray(array $set): array
     {
@@ -359,24 +360,31 @@ class Database
      *
      * Inserts a single row into the specified table, containing the values specified
      *
-     * @param string $table             the table into which to insert the row
-     * @param array  $set               the values with which to fill the new row
-     * @param bool   $autoescape        determines whether the values to be set
-     *                                  should automatically have the html escaped
-     * @param bool   $ignore            determines whether the insert throws an
-     *                                  error or is discarded when value exists in DB
-     * @param bool   $onDuplicateUpdate determines whether the row should be updated
-     *                                  upon unique key duplication
+     * @param string               $table             the table into which to
+     *                                                insert the row
+     * @param array<string,string> $set               the values with which to
+     *                                                fill the new row
+     * @param bool                 $autoescape        determines whether the
+     *                                                values to be set
+     *                                                should automatically
+     *                                                have the html escaped
+     * @param bool                 $ignore            determines whether the insert
+     *                                                throws an
+     *                                                error or is discarded
+     *                                                when value exists in DB
+     * @param bool                 $onDuplicateUpdate determines whether the row
+     *                                                should be updated
+     *                                                upon unique key duplication
      *
      * @return bool
      */
     private function _realinsert(
         string $table,
-        array  $set,
-        bool   $autoescape = true,
-        bool   $ignore = false,
-        bool   $onDuplicateUpdate = false
-    ) : bool {
+        array $set,
+        bool $autoescape = true,
+        bool $ignore = false,
+        bool $onDuplicateUpdate = false
+    ): bool {
         if ($ignore && $onDuplicateUpdate) {
             throw new DatabaseException(
                 'The Database::_realinsert() function does not accept both ignore
@@ -447,8 +455,8 @@ class Database
      * Replaces into the table such if there already exists a row with
      * the same primary key it will be replaced by the new row
      *
-     * @param string $table the table into which to insert the row
-     * @param array  $set   the values with which to fill the new row
+     * @param string               $table the table into which to insert the row
+     * @param array<string,string> $set   the values with which to fill the new row
      *
      * @return void
      * @access public
@@ -479,9 +487,10 @@ class Database
      * Updates a single row in the specified table. This will automatically escape
      * any HTML in the data being inserted for security.
      *
-     * @param string $table   the table into which to insert the row
-     * @param array  $set     the values with which to fill the new row
-     * @param array  $i_where the selection filter, joined as a boolean and
+     * @param string               $table   the table into which to insert the row
+     * @param array<string,string> $set     the values with which to fill the new row
+     * @param array<string,string> $i_where the selection filter, joined as a
+     *                                      boolean and
      *
      * @return void
      */
@@ -497,9 +506,11 @@ class Database
      * escape and should be used with caution, only when you know you need to
      * insert HTML and know that you can trust it.
      *
-     * @param string $table   the table into which to insert the row
-     * @param array  $set     the values with which to fill the new row
-     * @param array  $i_where the selection filter, joined as a boolean and
+     * @param string               $table   the table into which to insert the row
+     * @param array<string,string> $set     the values with which to fill the
+     *                                      new row
+     * @param array<string,string> $i_where the selection filter, joined as
+     *                                      a boolean and
      *
      * @return void
      */
@@ -517,14 +528,18 @@ class Database
      *
      * Updates a single row in the specified table
      *
-     * @param string $table      the table into which to insert the row
-     * @param array  $set        the values with which to fill the new row
-     * @param array  $i_where    the selection filter, joined as a boolean and
-     * @param bool   $autoescape determines whether the values to be set should
-     *                           automatically have the html escaped
+     * @param string               $table      the table into which to insert
+     *                                         the row
+     * @param array<string,string> $set        the values with which to fill
+     *                                         the new row
+     * @param array<string,string> $i_where    the selection filter, joined as
+     *                                         a boolean and
+     * @param bool                 $autoescape determines whether the values to
+     *                                         be set should
+     *                                         automatically have the html escaped
      *
      * @return bool Always true. An exception should be thrown if something goes
-     *              wrong.
+     *              wrong. FIXME This should probably be void.
      * @access public
      */
     private function _realupdate(
@@ -590,8 +605,9 @@ class Database
      *
      * Deletes a single row in the specified table
      *
-     * @param string $table the table into which to insert the row
-     * @param array  $where the selection filter, joined as a boolean and
+     * @param string               $table the table into which to insert the row
+     * @param array<string,string> $where the selection filter, joined as
+     *                                    a boolean and
      *
      * @return void
      * @access public
@@ -662,7 +678,7 @@ class Database
      *
      * @return PDOStatement A PDO prepared statement representing $query
      */
-    function prepare($query)
+    function prepare(string $query): PDOStatement
     {
         return $this->_PDO->prepare($query);
     }
@@ -671,19 +687,22 @@ class Database
      * Executes a previously prepared statements using the variable
      * bindings given.
      *
-     * @param PDOStatement $prepared The prepared statement
-     * @param array        $params   The values to bind to the statement
-     *                               while executing it
-     * @param array        $options  A list of key=>value pairs.
-     *                               - nofetch : to prevent the fetchAll
-     *                               function to be excuted. Useful for
-     *                               insert or update prepared statements.
-     *
-     * @return array An array of rows in the format ColName => Value after
-     *               executing the statement.
+     * @param PDOStatement         $prepared The prepared statement
+     * @param array<string,string> $params   The values to bind to the statement
+     *                                       while executing it
+     * @param array<string,string> $options  A list of key=>value pairs.
+     *                                       - nofetch : to prevent the
+     *                                       fetchAll function to be
+     *                                       excuted. Useful for insert
+     *                                       or update prepared
+     *                                       statements.
+     *
+     * @return array<int,array<string,string>> An array of rows in the format
+     *                                  ColName => Value after
+     *                                      executing the statement.
      */
     function execute(
-        $prepared,
+        PDOStatement $prepared,
         array $params,
         array $options = array()
     ): array {
@@ -711,10 +730,12 @@ class Database
     /**
      * Runs an SQL select statement as a prepared query
      *
-     * @param string $query  The SQL SELECT query to be run
-     * @param array  $params Values to use for binding to the prepared statement
+     * @param string               $query  The SQL SELECT query to be run
+     * @param array<string,string> $params Values to use for binding to the
+     *                                     prepared statement
      *
-     * @return array<string[]> An array of arrays containing the data.
+     * @return array<int,array<string,string>> An array of arrays containing
+     *                                          the data.
      *               The outside (non-associative array contains 1 element per
      *               row returned by the query, and each element is an associative
      *               array representing the row in the format ColumnName => Value
@@ -730,17 +751,19 @@ class Database
      * Runs an SQL select statement as a prepared query and re-indexes
      * the results using the given unique non-nullable key.
      *
-     * @param string $query     The SQL SELECT query to be run
-     * @param array  $params    Values to use for binding to the prepared statement
-     * @param string $uniqueKey Key to use when re-indexing, this key must be a
-     *                          single column, must be unique and must not be
-     *                          nullable
+     * @param string               $query     The SQL SELECT query to be run
+     * @param array<string,string> $params    Values to use for binding to the
+     *                                        prepared statement
+     * @param string               $uniqueKey Key to use when re-indexing, this
+     *                                        key must be a single column and
+     *                                        must be unique
      *
      * @throws LorisException     If the supplied key is empty or null
      * @throws DatabaseException  If the key is not part of the query itself
      * @throws DatabaseException  If the key is not unique within the resulting set
      *
-     * @return array An array of arrays containing the data. The outermost array is
+     * @return array<string,array<string,string>> An array of arrays containing
+     *                                  the data. The outermost array is
      *                  associative and uses the supplied $uniqueKey parameter as
      *                  a key for each of the sub-arrays with the format
      *                  rowPrimaryKey=>rowValuesArray. Each nested array represents
@@ -752,7 +775,7 @@ class Database
         string $query,
         array $params,
         string $uniqueKey
-    ) {
+    ): array {
 
         if (is_null($uniqueKey) || empty($uniqueKey)) {
             throw new LorisException(
@@ -805,13 +828,15 @@ class Database
      * associative array. Automatically adds a limit clause to the query being
      * run for efficiency.
      *
-     * @param string $query  The SQL SELECT query to be run
-     * @param array  $params Values to use for binding to prepared statement
+     * @param string               $query  The SQL SELECT query to be run
+     * @param array<string,string> $params Values to use for binding to prepared
+     *                                     statement
      *
-     * @return ?array Associative array of form ColumnName => Value for each column
-     *                in the first row of the query
+     * @return array<string,string>|null Associative array of form
+     *                              ColumnName => Value for each column in the
+     *                              first row of the query, or null.
      */
-    function pselectRow(string $query, array $params) : ?array
+    function pselectRow(string $query, array $params): ?array
     {
         $rows = $this->pselect($query . " LIMIT 2", $params);
         if (count($rows) > 1) {
@@ -824,18 +849,19 @@ class Database
 
     /**
      * Runs a query as a prepared statement and returns the values of the
-     * column given in the select statement. If multiple columns are given, an error
-     * is thrown.
+     * column given in the select statement. If multiple columns are given,
+     * an error is thrown.
      *
-     * @param string $query  The SQL SELECT query to be run
-     * @param array  $params Values to use for binding to prepared statement
+     * @param string               $query  The SQL SELECT query to be run
+     * @param array<string,string> $params Values to use for binding to prepared
+     *                                     statement
      *
      * @throws DatabaseException if the query selected more than one column
      *
-     * @return array Associative array of form rowID=>value containing all values
-     *               for the only column of the select statement
+     * @return array<string,string> Format: rowID=>value containing
+     *               all values for the only column of the select statement
      */
-    function pselectCol(string $query, array $params)
+    function pselectCol(string $query, array $params): array
     {
         $unprocessed = $this->pselect($query, $params);
 
@@ -861,25 +887,26 @@ class Database
      * the results using the given unique non-nullable key in the same
      * format as the pselectCol() function.
      *
-     * @param string $query     The SQL SELECT query to be run
-     * @param array  $params    Values to use for binding to the prepared statement
-     * @param string $uniqueKey Key to use when re-indexing, this key must be a
-     *                          single column, must be unique and must not be
-     *                          nullable
+     * @param string               $query     The SQL SELECT query to be run
+     * @param array<string,string> $params    Values to use for binding to the
+     *                                        prepared statement
+     * @param string               $uniqueKey Key to use when re-indexing, this
+     *                                        key must be a single column and
+     *                                        must be unique
      *
      * @throws LorisException     If the supplied key is empty or null
      * @throws DatabaseException  If the key is not part of the query itself or
      *                            if there are not exactly 2 columns selected
      * @throws DatabaseException  If the key is not unique within the resulting set
      *
-     * @return array Associative array of form uniqueKey=>value containing all
-     *               value for the non-uniqueKey element of the select statement
+     * @return array<string, string> Format: uniqueKey=>value containing all
+     *               values for the non-unique key element of the select statement
      */
     function pselectColWithIndexKey(
         string $query,
         array $params,
         string $uniqueKey
-    ) {
+    ): array {
 
         if (is_null($uniqueKey) || empty($uniqueKey)) {
             throw new LorisException(
@@ -946,8 +973,9 @@ class Database
      * returning an array of a single element) so that we can properly enforce
      * types.
      *
-     * @param string $query  The SQL statement to run
-     * @param array  $params Values to use for binding in the prepared statement
+     * @param string               $query  The SQL statement to run
+     * @param array<string,string> $params Values to use for binding in the
+     *                                     prepared statement
      *
      * @return mixed The value returned by the query: array, string, or false.
      */
@@ -966,9 +994,9 @@ class Database
      * Sets each hash element into the format key='value', and then
      * implodes the resultant array with the specified glue
      *
-     * @param string $glue      The glue to pass to php's implode function
-     * @param array  $dataArray The array with keys to implode
-     * @param string $clause    The type of clause set_|where_
+     * @param string                $glue      The glue to pass to implode()
+     * @param array<string, string> $dataArray The array with keys to implode
+     * @param string                $clause    The type of clause set_|where_
      *
      * @return string
      */
@@ -998,15 +1026,17 @@ class Database
      * Helper function to generate the string for the WHERE part of an update
      * or delete query. Generates the string in a prepared statement format.
      *
-     * @param string     $glue      The glue used to combine parts of the
-     *                              dataArray (ie " AND ").
-     * @param array      $dataArray The array representing the WHERE condition
-     *                              to be glued together into a string.
-     * @param array|null $exec_vals The values which are being bound to the
-     *                              query. Used to generate the prepared variable
-     *                              name.
-     * @param string     $prefix    A prefix to apply to prepared variable
-     *                              names.
+     * @param string                    $glue      The glue used to combine parts
+     *                                             of the dataArray (ie " AND ").
+     * @param array<string,string>      $dataArray The array representing the
+     *                                             WHERE condition to be glued
+     *                                             together into a string.
+     * @param array<string,string>|null $exec_vals The values which are being
+     *                                             bound to the query.
+     *                                             Used to generate the prepared
+     *                                             variable name.
+     * @param string                    $prefix    A prefix to apply to prepared
+     *                                             variable names.
      *
      * @return string A string that can be used to generate a prepared statement
      *                with appropriate variable names generated for data
@@ -1057,11 +1087,12 @@ class Database
      * Determines the difference between the old values and the new,
      * then saves a reference to that change
      *
-     * @param string $table the table into which to insert the row
-     * @param array  $set   the values with which to fill the new row
-     * @param string $where the selection filter, joined as a boolean and
-     * @param string $type  The type of change being tracked (*I*nsert,
-     *                      *U*pdate or *D*elete)
+     * @param string               $table the table into which to insert the row
+     * @param array<string,string> $set   the values with which to fill the new row
+     * @param string               $where the selection filter, joined as a
+     *                                    boolean and
+     * @param string               $type  The type of change being tracked
+     *                                    (*I*nsert,*U*pdate or *D*elete)
      *
      * @return void As a side-effect populates history table
      */
@@ -1184,10 +1215,13 @@ class Database
     /**
      * Print a query if showDatabaseQueries defined in config file
      *
-     * @param string $query  The query to replace
-     * @param array  $params The prepared statement parameters used for this query
-     *                       They will be replaced in the print statement so that the
-     *                       user knows what parameters were used.
+     * @param string                $query  The query to replace
+     * @param array<string, string> $params The prepared statement parameters
+     *                                      used for this query.
+     *                                      They will be replaced in the print
+     *                                      statement so that
+     *                                      the user knows what parameters
+     *                                      were used.
      *
      * @return void As a side-effect, prints to the screen if config option is
      *              enabled
@@ -1214,9 +1248,9 @@ class Database
      * without mocking every single query that needs to be used in
      * that test.
      *
-     * @param string $tableName The table name to fake
-     * @param array  $rowData   An array of data to be inserted into
-     *                          the fake table.
+     * @param string                $tableName The table name to fake
+     * @param array<string, string> $rowData   An array of data to be inserted into
+     *                                         the fake table.
      *
      * @return void
      */
@@ -1261,7 +1295,7 @@ class Database
      *
      * @param string $test_name The table to check for.
      *
-     * @return boolean true if the table exists
+     * @return bool true if the table exists
      */
     function tableExists(string $test_name): bool
     {
@@ -1292,7 +1326,7 @@ class Database
      * @param string $test_name The table to check for a column.
      * @param string $column    The column name to check the table for.
      *
-     * @return boolean true if the table has a the given column
+     * @return bool true if the table has a the given column
      */
     function columnExists(string $test_name, string $column): bool
     {
diff --git a/test/StrictTypesCS.xml b/test/StrictTypesCS.xml
new file mode 100644
index 00000000000..471e08162a2
--- /dev/null
+++ b/test/StrictTypesCS.xml
@@ -0,0 +1,36 @@
+<?xml version="1.0"?>
+<ruleset name="LORIS Strict Types Standard">
+    <description>An iterative effort to enforce the use of strict typing in LORIS</description>
+    <config name="installed_paths" value="../../slevomat/coding-standard"/>
+
+
+     <!-- Require strict types to be declared -->
+     <rule ref="SlevomatCodingStandard.TypeHints.DeclareStrictTypes">
+         <properties>
+             <property name="spacesCountAroundEqualsSign" value="0"/>
+         </properties>
+     </rule>
+
+     <!-- Force parameters to have type hints. Ignore errors about "useless"
+          annotations because other rulesets require that we have them. -->
+     <rule ref="SlevomatCodingStandard.TypeHints.ParameterTypeHint">
+         <exclude name="SlevomatCodingStandard.TypeHints.ParameterTypeHint.UselessAnnotation"/>
+         <properties>
+             <property name="enableObjectTypeHint" value="false"/>
+         </properties>
+    </rule>
+     <rule ref="SlevomatCodingStandard.TypeHints.ReturnTypeHint">
+         <exclude name="SlevomatCodingStandard.TypeHints.ReturnTypeHint.UselessAnnotation"/>
+         <properties>
+             <property name="enableObjectTypeHint" value="false"/>
+         </properties>
+     </rule>
+
+     <rule ref="SlevomatCodingStandard.TypeHints.LongTypeHints"/>
+
+     <rule ref="SlevomatCodingStandard.TypeHints.ReturnTypeHintSpacing"/>
+
+     <rule ref="SlevomatCodingStandard.TypeHints.NullableTypeForNullDefaultValue"/>
+
+     <rule ref="SlevomatCodingStandard.TypeHints.ParameterTypeHintSpacing"/>
+</ruleset>
diff --git a/test/run-php-linter.sh b/test/run-php-linter.sh
index 2359f607e8d..984fc55c1de 100755
--- a/test/run-php-linter.sh
+++ b/test/run-php-linter.sh
@@ -1,6 +1,7 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
+
 # Run PHP -l on everything to ensure there's no syntax
 # errors.
 find docs modules htdocs php src tools \
@@ -28,6 +29,7 @@ declare -a tools_list=(
     'single_use/Cleanup_multiple_firstVisits.php'
     'single_use/Convert_LorisMenuID_to_ModuleID.php'
 )
+
 # And on all PHP files in this array
 declare -a test_list=(
     'integrationtests/LorisIntegrationTest.class.inc'
@@ -42,6 +44,13 @@ vendor/bin/phpcs --standard=test/LorisCS.xml --extensions=php,inc \
     "${test_list[@]/#/test/}" \
     || exit $?;
 
+# Ensure strict typing is used in these files
+declare -a strict_libraries=(
+    'Database.class.inc'
+)
+
+vendor/bin/phpcs --standard=test/StrictTypesCS.xml --extensions=php,inc "${strict_libraries[@]/#/php/libraries/}" || exit $?;
+
 # Run PHPCS on src/ directory using a different ruleset conforming to PSR2.
 vendor/bin/phpcs --standard=test/SrcCS.xml --extensions=php/php src/ || exit $?;