diff --git a/gpx-rs/src/action/action.rs b/gpx-rs/src/action/action.rs
deleted file mode 100644
index 595a3b54a..000000000
--- a/gpx-rs/src/action/action.rs
+++ /dev/null
@@ -1,5 +0,0 @@
-use crate::state::StackEntry;
-
-pub trait Action {
-    fn apply(entry: &mut StackEntry) -> Result<(), &'static str>;
-}
diff --git a/gpx-rs/src/action/file.rs b/gpx-rs/src/action/file.rs
deleted file mode 100644
index ea14c4947..000000000
--- a/gpx-rs/src/action/file.rs
+++ /dev/null
@@ -1 +0,0 @@
-use crate::action::Action;
diff --git a/gpx-rs/src/action/mod.rs b/gpx-rs/src/action/mod.rs
deleted file mode 100644
index ff9d46028..000000000
--- a/gpx-rs/src/action/mod.rs
+++ /dev/null
@@ -1,5 +0,0 @@
-mod action;
-mod file;
-
-pub use action::*;
-pub use file::*;
diff --git a/gpx-rs/src/buffer/coordinates.rs b/gpx-rs/src/buffer/coordinates.rs
deleted file mode 100644
index 25282d4fa..000000000
--- a/gpx-rs/src/buffer/coordinates.rs
+++ /dev/null
@@ -1,4 +0,0 @@
-pub struct CoordinatesBuffer {
-    pub lng: Vec<f64>,
-    pub lat: Vec<f64>,
-}
diff --git a/gpx-rs/src/buffer/mod.rs b/gpx-rs/src/buffer/mod.rs
deleted file mode 100644
index 88a55c55a..000000000
--- a/gpx-rs/src/buffer/mod.rs
+++ /dev/null
@@ -1,5 +0,0 @@
-mod coordinates;
-mod statistics;
-
-pub use coordinates::*;
-pub use statistics::*;
diff --git a/gpx-rs/src/algorithm/mod.rs b/gpx-rs/src/core/algorithm/mod.rs
similarity index 100%
rename from gpx-rs/src/algorithm/mod.rs
rename to gpx-rs/src/core/algorithm/mod.rs
diff --git a/gpx-rs/src/algorithm/simplify.rs b/gpx-rs/src/core/algorithm/simplify.rs
similarity index 95%
rename from gpx-rs/src/algorithm/simplify.rs
rename to gpx-rs/src/core/algorithm/simplify.rs
index e9b95421e..e55f74638 100644
--- a/gpx-rs/src/algorithm/simplify.rs
+++ b/gpx-rs/src/core/algorithm/simplify.rs
@@ -1,6 +1,6 @@
 use crate::{
-    gpx::{TrackSegment, TrackSegmentIndex},
-    utils::crossarc,
+    core::gpx::{TrackSegment, TrackSegmentIndex},
+    core::utils::crossarc,
 };
 
 pub fn ramer_douglas_peucker<F>(
diff --git a/gpx-rs/src/algorithm/smooth.rs b/gpx-rs/src/core/algorithm/smooth.rs
similarity index 100%
rename from gpx-rs/src/algorithm/smooth.rs
rename to gpx-rs/src/core/algorithm/smooth.rs
diff --git a/gpx-rs/src/gpx/chunk.rs b/gpx-rs/src/core/gpx/chunk.rs
similarity index 96%
rename from gpx-rs/src/gpx/chunk.rs
rename to gpx-rs/src/core/gpx/chunk.rs
index 7d624ad09..52952f5f8 100644
--- a/gpx-rs/src/gpx/chunk.rs
+++ b/gpx-rs/src/core/gpx/chunk.rs
@@ -1,6 +1,6 @@
 use uuid::Uuid;
 
-use crate::gpx::{Trackpoint, Waypoint};
+use crate::{Trackpoint, Waypoint};
 
 static MAX_TRKPT_CHUNK_SIZE: usize = 4096;
 
diff --git a/gpx-rs/src/gpx/common.rs b/gpx-rs/src/core/gpx/common.rs
similarity index 100%
rename from gpx-rs/src/gpx/common.rs
rename to gpx-rs/src/core/gpx/common.rs
diff --git a/gpx-rs/src/gpx/file.rs b/gpx-rs/src/core/gpx/file.rs
similarity index 94%
rename from gpx-rs/src/gpx/file.rs
rename to gpx-rs/src/core/gpx/file.rs
index 8ccfcd8ef..1a035bb06 100644
--- a/gpx-rs/src/gpx/file.rs
+++ b/gpx-rs/src/core/gpx/file.rs
@@ -2,7 +2,7 @@ use std::rc::Rc;
 
 use uuid::Uuid;
 
-use crate::gpx::{Link, Track, WaypointChunk};
+use crate::{Link, Track, WaypointChunk};
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct FileId(pub Uuid);
diff --git a/gpx-rs/src/gpx/mod.rs b/gpx-rs/src/core/gpx/mod.rs
similarity index 100%
rename from gpx-rs/src/gpx/mod.rs
rename to gpx-rs/src/core/gpx/mod.rs
diff --git a/gpx-rs/src/gpx/segment.rs b/gpx-rs/src/core/gpx/segment.rs
similarity index 98%
rename from gpx-rs/src/gpx/segment.rs
rename to gpx-rs/src/core/gpx/segment.rs
index 4b3768391..de5d68989 100644
--- a/gpx-rs/src/gpx/segment.rs
+++ b/gpx-rs/src/core/gpx/segment.rs
@@ -2,7 +2,7 @@ use std::{ops::Index, rc::Rc};
 
 use uuid::Uuid;
 
-use crate::gpx::{Trackpoint, TrackpointChunk};
+use crate::{Trackpoint, TrackpointChunk};
 
 #[derive(Debug, PartialEq, Eq, Hash)]
 pub struct TrackSegmentId(Uuid);
@@ -174,8 +174,6 @@ impl<'a> Iterator for TrackSegmentIterator<'a> {
 
 #[cfg(test)]
 mod tests {
-    use crate::gpx::TrackpointChunk;
-
     use super::*;
 
     fn create_track_segment(nb_chunks: usize) -> TrackSegment {
diff --git a/gpx-rs/src/gpx/track.rs b/gpx-rs/src/core/gpx/track.rs
similarity index 94%
rename from gpx-rs/src/gpx/track.rs
rename to gpx-rs/src/core/gpx/track.rs
index 00f5f0a8f..2b015ce4d 100644
--- a/gpx-rs/src/gpx/track.rs
+++ b/gpx-rs/src/core/gpx/track.rs
@@ -1,6 +1,6 @@
 use uuid::Uuid;
 
-use crate::gpx::{Link, TrackSegment};
+use crate::{Link, TrackSegment};
 
 #[derive(Debug, PartialEq, Eq, Hash)]
 pub struct TrackId(Uuid);
diff --git a/gpx-rs/src/gpx/trackpoint.rs b/gpx-rs/src/core/gpx/trackpoint.rs
similarity index 92%
rename from gpx-rs/src/gpx/trackpoint.rs
rename to gpx-rs/src/core/gpx/trackpoint.rs
index d08800dff..32ee7a23a 100644
--- a/gpx-rs/src/gpx/trackpoint.rs
+++ b/gpx-rs/src/core/gpx/trackpoint.rs
@@ -1,4 +1,4 @@
-use crate::gpx::LngLat;
+use crate::LngLat;
 
 #[derive(Debug, Default)]
 pub struct Trackpoint {
diff --git a/gpx-rs/src/gpx/waypoint.rs b/gpx-rs/src/core/gpx/waypoint.rs
similarity index 93%
rename from gpx-rs/src/gpx/waypoint.rs
rename to gpx-rs/src/core/gpx/waypoint.rs
index 88b5ae335..f83b39ed7 100644
--- a/gpx-rs/src/gpx/waypoint.rs
+++ b/gpx-rs/src/core/gpx/waypoint.rs
@@ -1,6 +1,6 @@
 use uuid::Uuid;
 
-use crate::gpx::{Link, LngLat};
+use crate::{Link, LngLat};
 
 #[derive(Debug, PartialEq, Eq)]
 pub struct WaypointId(Uuid);
diff --git a/gpx-rs/src/io/mod.rs b/gpx-rs/src/core/io/mod.rs
similarity index 100%
rename from gpx-rs/src/io/mod.rs
rename to gpx-rs/src/core/io/mod.rs
diff --git a/gpx-rs/src/io/parse.rs b/gpx-rs/src/core/io/parse.rs
similarity index 99%
rename from gpx-rs/src/io/parse.rs
rename to gpx-rs/src/core/io/parse.rs
index 3f45f33ee..f3850f96d 100644
--- a/gpx-rs/src/io/parse.rs
+++ b/gpx-rs/src/core/io/parse.rs
@@ -1,6 +1,6 @@
 use std::rc::Rc;
 
-use crate::gpx::{
+use crate::{
     Author, File, Link, LngLat, Track, TrackSegment, Trackpoint, TrackpointChunk, Waypoint,
     WaypointChunk,
 };
diff --git a/gpx-rs/src/core/mod.rs b/gpx-rs/src/core/mod.rs
new file mode 100644
index 000000000..1e058e91f
--- /dev/null
+++ b/gpx-rs/src/core/mod.rs
@@ -0,0 +1,11 @@
+mod algorithm;
+pub(crate) mod gpx;
+mod io;
+pub(crate) mod statistics;
+mod utils;
+
+pub use algorithm::*;
+pub use gpx::*;
+pub use io::*;
+pub use statistics::*;
+pub use utils::*;
diff --git a/gpx-rs/src/statistics/mod.rs b/gpx-rs/src/core/statistics/mod.rs
similarity index 70%
rename from gpx-rs/src/statistics/mod.rs
rename to gpx-rs/src/core/statistics/mod.rs
index 0e9972d24..41e187567 100644
--- a/gpx-rs/src/statistics/mod.rs
+++ b/gpx-rs/src/core/statistics/mod.rs
@@ -1,7 +1,5 @@
-mod cache;
 mod statistics;
 mod utils;
 
-pub use cache::*;
 pub use statistics::*;
 pub use utils::*;
diff --git a/gpx-rs/src/statistics/statistics.rs b/gpx-rs/src/core/statistics/statistics.rs
similarity index 97%
rename from gpx-rs/src/statistics/statistics.rs
rename to gpx-rs/src/core/statistics/statistics.rs
index 6d2eb5f8a..2f734a2fd 100644
--- a/gpx-rs/src/statistics/statistics.rs
+++ b/gpx-rs/src/core/statistics/statistics.rs
@@ -1,9 +1,6 @@
 use crate::{
-    algorithm::ramer_douglas_peucker,
-    for_each_window,
-    gpx::{LngLat, LngLatBounds, TrackSegment, TrackSegmentIndex, Trackpoint},
-    statistics::sum_options,
-    utils::{distance, slope, speed, time_diff},
+    LngLat, LngLatBounds, TrackSegment, TrackSegmentIndex, Trackpoint, distance, for_each_window,
+    ramer_douglas_peucker, slope, speed, sum_options, time_diff,
 };
 
 #[derive(Default, Debug)]
@@ -290,7 +287,7 @@ pub struct SlopeSegment {
 mod tests {
     use std::{fs::File, io::Read};
 
-    use crate::io::parse;
+    use crate::parse;
 
     use super::*;
 
diff --git a/gpx-rs/src/statistics/utils.rs b/gpx-rs/src/core/statistics/utils.rs
similarity index 100%
rename from gpx-rs/src/statistics/utils.rs
rename to gpx-rs/src/core/statistics/utils.rs
diff --git a/gpx-rs/src/utils.rs b/gpx-rs/src/core/utils.rs
similarity index 99%
rename from gpx-rs/src/utils.rs
rename to gpx-rs/src/core/utils.rs
index 1fd5fe8a9..8673d827f 100644
--- a/gpx-rs/src/utils.rs
+++ b/gpx-rs/src/core/utils.rs
@@ -1,6 +1,6 @@
 use std::f64::consts::PI;
 
-use crate::gpx::LngLat;
+use crate::LngLat;
 
 static TO_RADIANS: f64 = PI / 180.0;
 static EARTH_RADIUS: f64 = 6371.0088;
diff --git a/gpx-rs/src/engine/derived/mod.rs b/gpx-rs/src/engine/derived/mod.rs
new file mode 100644
index 000000000..d4df4a7d3
--- /dev/null
+++ b/gpx-rs/src/engine/derived/mod.rs
@@ -0,0 +1,5 @@
+mod statistics_buffer;
+mod statistics_cache;
+
+pub use statistics_buffer::*;
+pub use statistics_cache::*;
diff --git a/gpx-rs/src/buffer/statistics.rs b/gpx-rs/src/engine/derived/statistics_buffer.rs
similarity index 97%
rename from gpx-rs/src/buffer/statistics.rs
rename to gpx-rs/src/engine/derived/statistics_buffer.rs
index 09c12528e..59536d33a 100644
--- a/gpx-rs/src/buffer/statistics.rs
+++ b/gpx-rs/src/engine/derived/statistics_buffer.rs
@@ -1,4 +1,4 @@
-use crate::statistics::{GlobalStatistics, Statistics, sum_options};
+use crate::{GlobalStatistics, Statistics, sum_options};
 
 #[derive(Debug, Default)]
 pub struct StatisticsBuffer {
diff --git a/gpx-rs/src/statistics/cache.rs b/gpx-rs/src/engine/derived/statistics_cache.rs
similarity index 95%
rename from gpx-rs/src/statistics/cache.rs
rename to gpx-rs/src/engine/derived/statistics_cache.rs
index adfcb7078..c5ba7c2b5 100644
--- a/gpx-rs/src/statistics/cache.rs
+++ b/gpx-rs/src/engine/derived/statistics_cache.rs
@@ -3,12 +3,7 @@ use std::{
     rc::Rc,
 };
 
-use crate::{
-    gpx::{File, Track, TrackSegment, TrackSegmentRevisionId},
-    selection::Selection,
-    state::StackEntry,
-    statistics::Statistics,
-};
+use crate::{File, Selection, StackEntry, Statistics, Track, TrackSegment, TrackSegmentRevisionId};
 
 #[derive(Debug, Default)]
 pub struct StatisticsCache {
diff --git a/gpx-rs/src/engine.rs b/gpx-rs/src/engine/engine.rs
similarity index 95%
rename from gpx-rs/src/engine.rs
rename to gpx-rs/src/engine/engine.rs
index dc26b5e75..24f74461a 100644
--- a/gpx-rs/src/engine.rs
+++ b/gpx-rs/src/engine/engine.rs
@@ -6,14 +6,7 @@ use js_sys::{Float64Array, Function, Int32Array};
 use uuid::Uuid;
 use wasm_bindgen::prelude::*;
 
-use crate::{
-    buffer::StatisticsBuffer,
-    gpx::{File, FileId},
-    io::parse,
-    selection::Selection,
-    state::{Stack, StackEntry},
-    statistics::StatisticsCache,
-};
+use crate::{File, FileId, Selection, Stack, StackEntry, StatisticsBuffer, StatisticsCache, parse};
 
 extern crate console_error_panic_hook;
 
diff --git a/gpx-rs/src/engine/mod.rs b/gpx-rs/src/engine/mod.rs
new file mode 100644
index 000000000..cad4b73ca
--- /dev/null
+++ b/gpx-rs/src/engine/mod.rs
@@ -0,0 +1,9 @@
+mod derived;
+mod engine;
+mod selection;
+mod state;
+
+pub use derived::*;
+pub use engine::*;
+pub use selection::*;
+pub use state::*;
diff --git a/gpx-rs/src/selection.rs b/gpx-rs/src/engine/selection.rs
similarity index 93%
rename from gpx-rs/src/selection.rs
rename to gpx-rs/src/engine/selection.rs
index ef93e74f7..e555f6826 100644
--- a/gpx-rs/src/selection.rs
+++ b/gpx-rs/src/engine/selection.rs
@@ -1,6 +1,6 @@
 use std::collections::HashSet;
 
-use crate::gpx::{FileId, TrackId, TrackSegmentId, WaypointId};
+use crate::{FileId, TrackId, TrackSegmentId, WaypointId};
 
 #[derive(Debug)]
 pub struct FileSelection {
diff --git a/gpx-rs/src/state/mod.rs b/gpx-rs/src/engine/state/mod.rs
similarity index 100%
rename from gpx-rs/src/state/mod.rs
rename to gpx-rs/src/engine/state/mod.rs
diff --git a/gpx-rs/src/state/stack.rs b/gpx-rs/src/engine/state/stack.rs
similarity index 99%
rename from gpx-rs/src/state/stack.rs
rename to gpx-rs/src/engine/state/stack.rs
index e70c121d7..b9db13534 100644
--- a/gpx-rs/src/state/stack.rs
+++ b/gpx-rs/src/engine/state/stack.rs
@@ -3,7 +3,7 @@ use std::{
     rc::Rc,
 };
 
-use crate::gpx::{File, FileId};
+use crate::{File, FileId};
 
 #[derive(Debug, Default)]
 pub struct Stack {
diff --git a/gpx-rs/src/lib.rs b/gpx-rs/src/lib.rs
index cd49cadf8..d6ea07f75 100644
--- a/gpx-rs/src/lib.rs
+++ b/gpx-rs/src/lib.rs
@@ -1,12 +1,5 @@
-mod action;
-mod algorithm;
-mod buffer;
+mod core;
 mod engine;
-mod gpx;
-mod io;
-mod selection;
-mod state;
-mod statistics;
-mod utils;
 
+pub use core::*;
 pub use engine::*;