diff --git a/minisql/src/error.rs b/minisql/src/error.rs
index 51ca0cf..6000c0e 100644
--- a/minisql/src/error.rs
+++ b/minisql/src/error.rs
@@ -1,5 +1,5 @@
 use crate::internals::row::ColumnPosition;
-use crate::internals::schema::{ColumnName, TableName};
+use crate::schema::{ColumnName, TableName};
 use crate::operation::InsertionValues;
 use crate::type_system::{DbType, Uuid, Value};
 
diff --git a/minisql/src/internals/mod.rs b/minisql/src/internals/mod.rs
index 864d9d7..f4723f3 100644
--- a/minisql/src/internals/mod.rs
+++ b/minisql/src/internals/mod.rs
@@ -1,4 +1,3 @@
 pub mod column_index;
 pub mod row;
-pub mod schema;
 pub mod table;
diff --git a/minisql/src/internals/table.rs b/minisql/src/internals/table.rs
index e5506e0..914d1ef 100644
--- a/minisql/src/internals/table.rs
+++ b/minisql/src/internals/table.rs
@@ -3,7 +3,7 @@ use std::collections::{BTreeMap, HashMap, HashSet};
 use crate::error::Error;
 use crate::internals::column_index::ColumnIndex;
 use crate::internals::row::{ColumnPosition, Row};
-use crate::internals::schema::{ColumnName, TableSchema, TableName};
+use crate::schema::{ColumnName, TableSchema, TableName};
 use crate::result::DbResult;
 use crate::type_system::{IndexableValue, Uuid, Value};
 
@@ -206,7 +206,7 @@ impl Table {
                     let column_name: ColumnName = self
                         .schema
                         .column_name_from_column_position(column_position)?;
-                    let type_ = self.schema.types[column_position];
+                    let type_ = self.schema.column_type(column_position);
                     Err(Error::ValueDoesNotMatchExpectedType(
                         self.table_name().clone(),
                         column_name,
diff --git a/minisql/src/interpreter.rs b/minisql/src/interpreter.rs
index 4bd3f35..7a3bad3 100644
--- a/minisql/src/interpreter.rs
+++ b/minisql/src/interpreter.rs
@@ -1,6 +1,6 @@
 use crate::error::Error;
 use crate::internals::row::{ColumnPosition, Row};
-use crate::internals::schema::{TableName, TableSchema};
+use crate::schema::{TableName, TableSchema};
 use crate::internals::table::Table;
 use crate::operation::{ColumnSelection, Condition, Operation};
 use crate::result::DbResult;
diff --git a/minisql/src/lib.rs b/minisql/src/lib.rs
new file mode 100644
index 0000000..b8e95c3
--- /dev/null
+++ b/minisql/src/lib.rs
@@ -0,0 +1,7 @@
+pub mod schema;
+pub mod interpreter;
+pub mod operation;
+pub mod type_system;
+mod error;
+mod internals;
+mod result;
diff --git a/minisql/src/main.rs b/minisql/src/main.rs
deleted file mode 100644
index 9a4f292..0000000
--- a/minisql/src/main.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-mod error;
-mod internals;
-mod interpreter;
-mod operation;
-mod result;
-mod type_system;
-
-fn main() {
-    interpreter::example();
-}
diff --git a/minisql/src/operation.rs b/minisql/src/operation.rs
index a5fd0b7..3b060c9 100644
--- a/minisql/src/operation.rs
+++ b/minisql/src/operation.rs
@@ -1,4 +1,4 @@
-use crate::internals::schema::{ColumnName, TableName, TableSchema};
+use crate::schema::{ColumnName, TableName, TableSchema};
 use crate::type_system::Value;
 
 // ==============SQL operations================
diff --git a/minisql/src/internals/schema.rs b/minisql/src/schema.rs
similarity index 93%
rename from minisql/src/internals/schema.rs
rename to minisql/src/schema.rs
index c23c24a..c9574ac 100644
--- a/minisql/src/internals/schema.rs
+++ b/minisql/src/schema.rs
@@ -11,16 +11,16 @@ use std::collections::HashMap;
 #[derive(Debug)]
 pub struct TableSchema {
     table_name: TableName, // used for descriptive errors
-    pub primary_key: ColumnPosition,
-    pub column_name_position_mapping: BiMap<ColumnName, ColumnPosition>,
-    pub types: Vec<DbType>,
+    primary_key: ColumnPosition,
+    column_name_position_mapping: BiMap<ColumnName, ColumnPosition>,
+    types: Vec<DbType>,
 }
 
 pub type TableName = String;
 pub type ColumnName = String;
 
 impl TableSchema {
-    pub fn new(table_name: TableName, primary_key: ColumnPosition, column_name_position_map: Vec<(ColumnName, ColumnPosition)>, types: Vec<DbType>) -> Self {
+    pub(crate) fn new(table_name: TableName, primary_key: ColumnPosition, column_name_position_map: Vec<(ColumnName, ColumnPosition)>, types: Vec<DbType>) -> Self {
         let mut column_name_position_mapping: BiMap<ColumnName, ColumnPosition> = BiMap::new();
         for (column_name, column_position) in column_name_position_map {
             column_name_position_mapping.insert(column_name, column_position);
@@ -32,6 +32,10 @@ impl TableSchema {
         &self.table_name
     }
 
+    pub fn column_type(&self, column_position: ColumnPosition) -> DbType {
+        self.types[column_position]
+    }
+
     fn get_column(&self, column_name: &ColumnName) -> DbResult<(DbType, ColumnPosition)> {
         match self.column_name_position_mapping.get_by_left(column_name) {
             Some(column_position) => match self.types.get(*column_position) {