diff --git a/examples/al-displayFITS.html b/examples/al-displayFITS.html
index 90746da1..07fe1cba 100644
--- a/examples/al-displayFITS.html
+++ b/examples/al-displayFITS.html
@@ -26,9 +26,9 @@
                 minCut: 5000,
                 maxCut: 17000,
             }, // no optional params
-            (ra, dec, fov, image) => { // ra, dec and fov are centered around the fits image 
+            (ra, dec, fov, image) => { // ra, dec and fov are centered around the fits image
+                console.log(image)
                 image.setColormap("magma", {stretch: "asinh"});                
-                
                 aladin.gotoRaDec(ra, dec);
                 aladin.setFoV(fov);
             }
diff --git a/examples/index.html b/examples/index.html
index 4dc60490..5752a61e 100644
--- a/examples/index.html
+++ b/examples/index.html
@@ -9,6 +9,8 @@
 
 <script type="text/javascript">
     var aladin;
+    console.log("jkjkjkj")
+
     A.init.then(() => {
         /*aladin = A.aladin('#aladin-lite-div', {fov: 360, fullScreen: true, cooFrame: 'galactic'});
         aladin.setProjection('MOL');
diff --git a/src/core/Cargo.toml b/src/core/Cargo.toml
index 5e795754..ac2de09b 100644
--- a/src/core/Cargo.toml
+++ b/src/core/Cargo.toml
@@ -34,6 +34,7 @@ fitsrs = "0.1.1"
 enum_dispatch = "0.3.8"
 wasm-bindgen = "0.2.79"
 wasm-streams = "0.3.0"
+async-channel = "1.8.0"
 al-core = { path = "./al-core" }
 al-task-exec = { path = "./al-task-exec" }
 al-api = { path = "./al-api" }
diff --git a/src/core/al-api/src/fov.rs b/src/core/al-api/src/fov.rs
index 768e571a..b21b3580 100644
--- a/src/core/al-api/src/fov.rs
+++ b/src/core/al-api/src/fov.rs
@@ -1,5 +1,8 @@
 use wasm_bindgen::prelude::*;
 
+use serde::{Deserialize, Serialize};
+
+#[derive(Deserialize, Serialize)]
 #[wasm_bindgen]
 pub struct FoV {
     /// Position of the field of view
diff --git a/src/core/al-core/src/texture/mod.rs b/src/core/al-core/src/texture/mod.rs
index 7289de32..afaa3e51 100644
--- a/src/core/al-core/src/texture/mod.rs
+++ b/src/core/al-core/src/texture/mod.rs
@@ -25,6 +25,7 @@ struct Texture2DMeta {
 }
 
 use web_sys::WebGlTexture;
+#[derive(Clone)]
 pub struct Texture2D {
     pub texture: Option<WebGlTexture>,
 
diff --git a/src/core/src/app.rs b/src/core/src/app.rs
index d008cb80..e48b1aad 100644
--- a/src/core/src/app.rs
+++ b/src/core/src/app.rs
@@ -28,6 +28,7 @@ use al_api::{
     grid::GridCfg,
     hips::{ImageMetadata, HiPSCfg, FITSCfg}, fov::FoV,
 };
+use wasm_bindgen_futures::JsFuture;
 use crate::Abort;
 use super::coosys;
 use cgmath::Vector4;
@@ -87,10 +88,17 @@ pub struct App {
     colormaps: Colormaps,
 
     projection: ProjectionType,
+
+    // Async data receivers
+    fits_send: async_channel::Sender<FitsCfg>,
+    fits_recv: async_channel::Receiver<FitsCfg>,
+
+    ack_send: async_channel::Sender<()>,
+    ack_recv: async_channel::Receiver<()>,
 }
 
 use cgmath::{Vector2, Vector3};
-use futures::stream::StreamExt; // for `next`
+use futures::{stream::StreamExt, io::BufReader}; // for `next`
 
 /// State for inertia
 struct InertiaAnimation {
@@ -189,6 +197,9 @@ impl App {
 
         gl.clear_color(0.15, 0.15, 0.15, 1.0);
 
+        let (fits_send, fits_recv) = async_channel::unbounded::<FitsCfg>();
+        let (ack_send, ack_recv) = async_channel::unbounded::<()>();
+
         Ok(App {
             gl,
             start_time_frame,
@@ -229,6 +240,11 @@ impl App {
 
             colormaps,
             projection,
+
+            fits_send,
+            fits_recv,
+            ack_send,
+            ack_recv
         })
     }
 
@@ -692,6 +708,20 @@ impl App {
             }
         }*/
 
+        // Check for async retrieval
+        if let Ok(fits) = self.fits_recv.try_recv() {
+            al_core::log("received");
+            self.layers.add_image_fits(fits, &mut self.camera, &self.projection)?;
+            self.request_redraw = true;
+
+            // Send the ack to the js promise so that she finished
+            let ack_send = self.ack_send.clone();
+            wasm_bindgen_futures::spawn_local(async move {
+                ack_send.send(()).await
+                    .unwrap_throw();
+            })
+        }
+
         self.draw(false)?;
 
         Ok(())
@@ -853,29 +883,74 @@ impl App {
         Ok(())
     }
 
-    pub(crate) fn add_image_fits(&mut self, cfg: FITSCfg, bytes: &[u8]) -> Result<FoV, JsValue> {
+    pub(crate) fn add_image_fits(&mut self, cfg: FITSCfg) -> Result<js_sys::Promise, JsValue> {
         let FITSCfg { layer, url, meta } = cfg;
+        al_core::log(&format!("url: {:?}", url));
+        let gl = self.gl.clone();
+
+        let fits_sender = self.fits_send.clone();
+        let ack_recv = self.ack_recv.clone();
+        let fut = async move {
+            use wasm_streams::ReadableStream;
+            use js_sys::Uint8Array;
+            use web_sys::Response;
+            use web_sys::window;
+            use wasm_bindgen_futures::JsFuture;
+            use futures::StreamExt;
+            use wasm_bindgen::JsCast;
+            use crate::renderable::image::FitsImage;
+            use futures::TryStreamExt;
+    
+            let window = window().unwrap();
+            let resp_value = JsFuture::from(window.fetch_with_str(&url))
+                .await?;
+            let resp: Response = resp_value.dyn_into()?;
         
-        let fits = FitsImage::new(&self.gl, bytes)?;
-        let center = fits.get_center();
-        let fov = FoV {
-            ra: center.lon().to_degrees(),
-            dec: center.lat().to_degrees(),
-            fov: 1.0
+            // Get the response's body as a JS ReadableStream
+            let raw_body = resp.body().unwrap();
+            let body = ReadableStream::from_raw(raw_body.dyn_into()?);
+
+            al_core::log("begin to parse fits!");
+            // Convert the JS ReadableStream to a Rust stream
+            let bytes_reader = body
+                .into_stream()
+                .map_ok(|js_value| js_value.dyn_into::<Uint8Array>().unwrap_throw().to_vec())
+                .map_err(|_js_error| std::io::Error::new(std::io::ErrorKind::Other, "failed to read"))
+                .into_async_read();
+
+            let fits = FitsImage::new_async(&gl, BufReader::new(bytes_reader)).await?;
+            al_core::log("fits parsed");
+
+            let center = fits.get_center();
+            let ra = center.lon().to_degrees();
+            let dec = center.lat().to_degrees();
+            let fov = 1.0;
+
+            let fits_cfg = FitsCfg {
+                fits: fits,
+                layer: layer,
+                url: url,
+                meta: meta
+            };
+
+            fits_sender.send(fits_cfg).await
+                .unwrap();
+
+            // Wait for the ack
+            if let Ok(_) = ack_recv.recv().await {
+                let fov = FoV {
+                    ra: ra,
+                    dec: dec,
+                    fov: fov,
+                };
+                Ok(serde_wasm_bindgen::to_value(&fov).unwrap())
+            } else {
+                Err(JsValue::from_str("Problem receving fits"))
+            }
         };
-
-        let cfg = FitsCfg {
-            layer,
-            url,
-            fits,
-            meta,
-        };
-        self.layers.add_image_fits(cfg, &mut self.camera, &self.projection)?;
-
-        // Once its added, request the tiles in the view (unless the viewer is at depth 0)
-        self.request_redraw = true;
-
-        Ok(fov)
+        
+        let promise = wasm_bindgen_futures::future_to_promise(fut);
+        Ok(promise)
     }
 
     pub(crate) fn get_layer_cfg(&self, layer: &str) -> Result<ImageMetadata, JsValue> {
diff --git a/src/core/src/lib.rs b/src/core/src/lib.rs
index c6ecf134..dc24a354 100644
--- a/src/core/src/lib.rs
+++ b/src/core/src/lib.rs
@@ -66,6 +66,7 @@ mod utils;
 
 use math::projection::*;
 use wasm_bindgen::prelude::*;
+use wasm_bindgen_futures::JsFuture;
 
 mod app;
 pub mod async_task;
@@ -98,6 +99,7 @@ use al_api::hips::HiPSProperties;
 use al_api::coo_system::CooSystem;
 use al_api::color::{Color, ColorRGBA};
 use al_api::fov::FoV;
+use al_api::hips::FITSCfg;
 
 use al_core::Colormap;
 use al_core::{WebGlContext};
@@ -266,7 +268,7 @@ impl WebClient {
     /// # Examples
     ///
     /// ```javascript
-    /// let al = new Aladin.wasmLibs.webgl.WebClient(...);
+    /// let al = new Aladin.wasmLibs.core.WebClient(...);
     /// const panstarrs = {
     ///     properties: {
     ///         url: "http://alasky.u-strasbg.fr/Pan-STARRS/DR1/r",
@@ -309,10 +311,10 @@ impl WebClient {
     }
 
     #[wasm_bindgen(js_name = addImageFITS)]
-    pub fn add_image_fits(&mut self, fits_cfg: JsValue, bytes: &[u8]) -> Result<FoV, JsValue> {
-        let fits_cfg = serde_wasm_bindgen::from_value(fits_cfg)?;
+    pub fn add_image_fits(&mut self, fits_cfg: JsValue) -> Result<js_sys::Promise, JsValue> {
+        let fits_cfg: FITSCfg = serde_wasm_bindgen::from_value(fits_cfg)?;
 
-        self.app.add_image_fits(fits_cfg, bytes)
+        self.app.add_image_fits(fits_cfg)
     }
 
     #[wasm_bindgen(js_name = removeLayer)]
diff --git a/src/core/src/renderable/image.rs b/src/core/src/renderable/image.rs
index 0bdabefb..e498ce32 100644
--- a/src/core/src/renderable/image.rs
+++ b/src/core/src/renderable/image.rs
@@ -1,6 +1,7 @@
 use std::vec;
 
 use al_api::hips::ImageMetadata;
+use futures::StreamExt;
 use moclib::moc::range::RangeMOC;
 use moclib::qty::Hpx;
 use moclib::elem::cell::Cell;
@@ -13,7 +14,7 @@ use web_sys::WebGl2RenderingContext;
 use al_api::cell::HEALPixCellProjeted;
 use al_api::coo_system::CooSystem;
 
-use al_core::{VertexArrayObject, Texture2D};
+use al_core::{VertexArrayObject, Texture2D, pixel};
 use al_core::WebGlContext;
 use al_core::VecData;
 use al_core::webgl_ctx::GlWrapper;
@@ -26,16 +27,18 @@ use crate::ShaderManager;
 use crate::Colormaps;
 
 use fitsrs::{
-    fits::Fits,
+    fits::{AsyncFits, Fits},
     hdu::{
+        data_async::DataOwned,
         HDU,
+        AsyncHDU,
         data::DataBorrowed
     }
 };
 use wcs::ImgXY;
 use wcs::WCS;
 
-use wasm_bindgen::JsValue;
+use wasm_bindgen::{JsValue, UnwrapThrowExt};
 
 pub struct FitsImage {
     // The vertex array object of the screen in NDC
@@ -58,13 +61,221 @@ pub struct FitsImage {
     center: LonLat,
 }
 
+use crate::time::Time;
+use futures::io::BufReader;
+
 impl FitsImage {
-    pub fn new<'a>(
+    pub fn from_bytes(
         gl: &WebGlContext,
-        raw_bytes: &'a [u8],
+        bytes: &[u8]
     ) -> Result<Self, JsValue> {
         // Load the fits file
-        let Fits { hdu: HDU { header, data } } = Fits::from_reader(raw_bytes)
+        al_core::log("jdjdjdj start");
+
+        let Fits { hdu: HDU { header, data } } = Fits::from_reader(bytes)
+            .map_err(|_| JsValue::from_str("Fits cannot be parsed"))?;
+
+        al_core::log("jdjdjdj");
+        let scale = header
+            .get_parsed::<f64>(b"BSCALE  ")
+            .unwrap_or(Ok(1.0))
+            .unwrap() as f32;
+        let offset = header
+            .get_parsed::<f64>(b"BZERO   ")
+            .unwrap_or(Ok(0.0))
+            .unwrap() as f32;
+        let blank = header
+            .get_parsed::<f64>(b"BLANK   ")
+            .unwrap_or(Ok(std::f64::NAN))
+            .unwrap() as f32;
+        al_core::log("jdjdjdj2");
+
+        // Create a WCS from a specific header unit
+        let wcs = WCS::new(&header).map_err(|_| JsValue::from_str("Failed to parse the WCS"))?;
+
+        let (w, h) = wcs.img_dimensions();
+        let width = w as f64;
+        let height = h as f64;
+        let tex_params = &[
+            (
+                WebGl2RenderingContext::TEXTURE_MIN_FILTER,
+                WebGl2RenderingContext::NEAREST,
+            ),
+            (
+                WebGl2RenderingContext::TEXTURE_MAG_FILTER,
+                WebGl2RenderingContext::NEAREST,
+            ),
+            // Prevents s-coordinate wrapping (repeating)
+            (
+                WebGl2RenderingContext::TEXTURE_WRAP_S,
+                WebGl2RenderingContext::CLAMP_TO_EDGE,
+            ),
+            // Prevents t-coordinate wrapping (repeating)
+            (
+                WebGl2RenderingContext::TEXTURE_WRAP_T,
+                WebGl2RenderingContext::CLAMP_TO_EDGE,
+            ),
+        ];
+        al_core::log("jdjdjdj3");
+
+        let texture = match data {
+            DataBorrowed::U8(data) => {
+                Texture2D::create_from_raw_pixels::<al_core::image::format::R8UI>(gl, w as i32, h as i32, tex_params, Some(&data))?
+            },
+            DataBorrowed::I16(data) => {
+                Texture2D::create_from_raw_pixels::<al_core::image::format::R16I>(gl, w as i32, h as i32, tex_params, Some(&data))?
+            },
+            DataBorrowed::I32(data) => {
+                al_core::log("jdjdjd4");
+                al_core::log("jdjdjdj5");
+
+                Texture2D::create_from_raw_pixels::<al_core::image::format::R32I>(gl, w as i32, h as i32, tex_params, Some(&data))?
+            },
+            DataBorrowed::I64(data) => {
+                let values: Vec<f32> = data.iter().map(|v| {
+                    *v as f32
+                })
+                .collect();
+
+                Texture2D::create_from_raw_pixels::<al_core::image::format::R32F>(gl, w as i32, h as i32, tex_params, Some(&values))?
+            },
+            DataBorrowed::F32(data) => {
+                Texture2D::create_from_raw_pixels::<al_core::image::format::R32F>(gl, w as i32, h as i32, tex_params, Some(data))?
+            },
+            DataBorrowed::F64(data) => {
+                let values: Vec<f32> = data.iter().map(|v| {
+                    *v as f32
+                })
+                .collect();
+
+                Texture2D::create_from_raw_pixels::<al_core::image::format::R32F>(gl, w as i32, h as i32, tex_params, Some(&values))?
+            },
+        };
+
+        let bl = wcs.unproj_lonlat(&ImgXY::new(0.0, 0.0)).ok_or(JsValue::from_str("(0, 0) px cannot be unprojected"))?;
+        let br = wcs.unproj_lonlat(&ImgXY::new(width - 1.0, 0.0)).ok_or(JsValue::from_str("(w - 1, 0) px cannot be unprojected"))?;
+        let tr = wcs.unproj_lonlat(&ImgXY::new(width - 1.0, height - 1.0)).ok_or(JsValue::from_str("(w - 1, h - 1) px cannot be unprojected"))?;
+        let tl = wcs.unproj_lonlat(&ImgXY::new(0.0, height - 1.0)).ok_or(JsValue::from_str("(0, h - 1) px cannot be unprojected"))?;
+
+        let center = wcs.unproj_lonlat(&ImgXY::new(width / 2.0, height / 2.0)).ok_or(JsValue::from_str("(w / 2, h / 2) px cannot be unprojected"))?;
+        
+        let mut num_moc_cells = std::usize::MAX;
+        let mut depth = 11;
+        let mut moc = RangeMOC::new_empty(0);
+        while num_moc_cells > 5 && depth > 3 {
+            depth = depth - 1;
+            moc = RangeMOC::from_polygon_with_control_point(
+                &[
+                    (bl.lon(), bl.lat()),
+                    (br.lon(), br.lat()),
+                    (tr.lon(), tr.lat()),
+                    (tl.lon(), tl.lat()),
+                ],
+                (center.lon(), center.lat()),
+                depth
+            );
+
+            num_moc_cells = (&moc).into_range_moc_iter().cells().count();
+        }
+        
+        let pos = vec![];
+        let uv = vec![];
+        let indices = vec![];
+        // Define the buffers
+        let vao = {
+            let mut vao = VertexArrayObject::new(gl);
+            
+            #[cfg(feature = "webgl2")]
+            vao.bind_for_update()
+                // layout (location = 0) in vec2 ndc_pos;
+                .add_array_buffer_single(
+                    2,
+                    "ndc_pos",
+                    WebGl2RenderingContext::DYNAMIC_DRAW,
+                    VecData::<f32>(&pos),
+                )
+                .add_array_buffer_single(
+                    2,
+                    "uv",
+                    WebGl2RenderingContext::DYNAMIC_DRAW,
+                    VecData::<f32>(&uv),
+                )
+                // Set the element buffer
+                .add_element_buffer(
+                    WebGl2RenderingContext::DYNAMIC_DRAW,
+                    VecData::<u32>(&indices),
+                )
+                .unbind();
+            #[cfg(feature = "webgl1")]
+            vao.bind_for_update()
+                .add_array_buffer_single(
+                    2,
+                    "ndc_pos",
+                    WebGl2RenderingContext::DYNAMIC_DRAW,
+                    VecData::<f32>(&pos),
+                )
+                .add_array_buffer_single(
+                    2,
+                    "uv",
+                    WebGl2RenderingContext::DYNAMIC_DRAW,
+                    VecData::<f32>(&uv),
+                )
+                // Set the element buffer
+                .add_element_buffer(
+                    WebGl2RenderingContext::DYNAMIC_DRAW,
+                    VecData::<u32>(&indices),
+                )
+                .unbind();
+
+            vao
+        };
+
+        // Automatic methods to compute the min and max cut values
+        /*let mut values = values.into_iter()
+            .filter(|x| !x.is_nan() && *x != blank)
+            .collect::<Vec<_>>();
+        
+        let n = values.len();
+        let first_pct_idx = (0.05 * (n as f32)) as usize;
+        let last_pct_idx = (0.95 * (n as f32)) as usize;
+
+        let min_val = crate::utils::select_kth_smallest(&mut values[..], 0, n - 1, first_pct_idx);
+        let max_val = crate::utils::select_kth_smallest(&mut values[..], 0, n - 1, last_pct_idx);
+        */
+        //al_core::log(&format!("values: {} {}", min_val, max_val));
+
+        let gl = gl.clone();
+        let image = FitsImage {
+            vao,
+            wcs,
+            moc,
+            gl,
+
+            pos,
+            uv,
+            indices,
+
+            texture,
+            scale,
+            offset,
+            blank,
+
+            center,
+        };
+
+        Ok(image)
+    }
+
+    pub async fn new_async<'a, R>(
+        gl: &WebGlContext,
+        reader: BufReader<R>,
+    ) -> Result<Self, JsValue>
+    where
+        R: futures::AsyncRead + std::marker::Unpin + std::fmt::Debug
+    {
+        // Load the fits file
+        let AsyncFits { hdu: AsyncHDU { header, data } } = AsyncFits::from_reader(reader)
+            .await
             .map_err(|_| JsValue::from_str("Fits cannot be parsed"))?;
 
         let scale = header
@@ -108,36 +319,70 @@ impl FitsImage {
         ];
 
         let texture = match data {
-            DataBorrowed::U8(data) => {
-                Texture2D::create_from_raw_pixels::<al_core::image::format::R8UI>(gl, w as i32, h as i32, tex_params, Some(data))?
+            DataOwned::U8(data) => {
+                let data = data.collect::<Vec<u8>>().await;
+                Texture2D::create_from_raw_pixels::<al_core::image::format::R8UI>(gl, w as i32, h as i32, tex_params, Some(&data))?
             },
-            DataBorrowed::I16(data) => {
-                let values: Vec<f32> = data.into_iter().map(|v| {
-                    *v as f32
+            DataOwned::I16(data) => {
+                let values: Vec<f32> = data.map(|v| {
+                    v as f32
                 })
-                .collect();
+                .collect().await;
 
                 Texture2D::create_from_raw_pixels::<al_core::image::format::R32F>(gl, w as i32, h as i32, tex_params, Some(&values))?
             },
-            DataBorrowed::I32(data) => {
-                Texture2D::create_from_raw_pixels::<al_core::image::format::R32I>(gl, w as i32, h as i32, tex_params, Some(data))?
+            DataOwned::I32(mut data) => {
+                let texture = Texture2D::create_from_raw_pixels::<al_core::image::format::R32F>(gl, w as i32, h as i32, tex_params, None)?;
+                let tex_bound = texture.bind();
+                let mut dy = 0;
+                let mut pixels_processed = 0;
+                let tot_pixels = w * h;
+                let mut bytes_chunk = Vec::new();
+
+                while pixels_processed < tot_pixels {
+                    let chunk_num_pixels = w; // todo adapt the size of the chunk
+
+                    bytes_chunk.clear();
+                    for _ in 0..chunk_num_pixels {
+                        let value = data.next().await.unwrap_throw() as f32;
+                        bytes_chunk.extend(value.to_le_bytes());
+                    }
+
+                    tex_bound.tex_sub_image_2d_with_i32_and_i32_and_u32_and_type_and_opt_u8_array(
+                        0,
+                        dy,
+                        w as i32,
+                        1,
+                        Some(&bytes_chunk)
+                    );
+                    dy += 1;
+
+                    pixels_processed += chunk_num_pixels;
+                }
+
+                texture
             },
-            DataBorrowed::I64(data) => {
-                let values: Vec<f32> = data.into_iter().map(|v| {
-                    *v as f32
+            DataOwned::I64(data) => {
+                let values: Vec<f32> = data.map(|v| {
+                    v as f32
                 })
-                .collect();
+                .collect().await;
 
                 Texture2D::create_from_raw_pixels::<al_core::image::format::R32F>(gl, w as i32, h as i32, tex_params, Some(&values))?
             },
-            DataBorrowed::F32(data) => {
-                Texture2D::create_from_raw_pixels::<al_core::image::format::R32F>(gl, w as i32, h as i32, tex_params, Some(data))?
+            DataOwned::F32(data) => {
+                al_core::log("f32");
+
+                let values: Vec<f32> = data.collect().await;
+                Texture2D::create_from_raw_pixels::<al_core::image::format::R32F>(gl, w as i32, h as i32, tex_params, Some(&values))?
             },
-            DataBorrowed::F64(data) => {
-                let values: Vec<f32> = data.into_iter().map(|v| {
-                    *v as f32
+            DataOwned::F64(data) => {
+                al_core::log("f64");
+
+                let values: Vec<f32> = data.map(|v| {
+                    v as f32
                 })
-                .collect();
+                .collect().await;
 
                 Texture2D::create_from_raw_pixels::<al_core::image::format::R32F>(gl, w as i32, h as i32, tex_params, Some(&values))?
             },
diff --git a/src/core/src/utils.rs b/src/core/src/utils.rs
index 5d4be7dd..e4caf366 100644
--- a/src/core/src/utils.rs
+++ b/src/core/src/utils.rs
@@ -45,6 +45,11 @@ pub unsafe fn transmute_boxed_slice<I, O>(s: Box<[I]>) -> Box<[O]> {
     Box::from_raw(out_slice_ptr)
 }
 
+pub unsafe fn transmute_vec_to_u8<I>(mut s: Vec<I>) -> Vec<u8> {
+    s.set_len(std::mem::size_of_val(&s[..]));
+    std::mem::transmute(s)
+}
+
 /// Select the kth smallest element in a slice
 /// 
 /// This is a basic implementation of quickselect algorithm: https://fr.wikipedia.org/wiki/Quickselect
diff --git a/src/js/Aladin.js b/src/js/Aladin.js
index 8e440cb8..6a294fab 100644
--- a/src/js/Aladin.js
+++ b/src/js/Aladin.js
@@ -56,12 +56,13 @@ import { CooGrid } from "./gui/CooGrid.js";
 import { ALEvent } from "./events/ALEvent.js";
 import { Color } from './Color.js';
 import { ColorCfg } from './ColorCfg.js';
+import { ImageFITS } from "./ImageFITS.js";
 
 import $ from 'jquery';
 
 // Import aladin css inside the project
 import './../css/aladin.css';
-import { ImageFITS } from "./ImageFITS.js";
+
 
 export let Aladin = (function () {
 
@@ -73,7 +74,7 @@ export let Aladin = (function () {
         if ($(aladinDiv).length == 0) {
             return;
         }
-        this.webglAPI = null;
+        this.wasm = null;
         var self = this;
 
         // if not options was set, try to retrieve them from the query string
@@ -679,7 +680,7 @@ export let Aladin = (function () {
 
             coo.parse(targetName);
             // Convert from view coo sys to icrsj2000
-            const [ra, dec] = this.view.aladin.webglAPI.viewToICRSJ2000CooSys(coo.lon, coo.lat);
+            const [ra, dec] = this.wasm.viewToICRSJ2000CooSys(coo.lon, coo.lat);
             this.view.pointTo(ra, dec, options);
 
             (typeof successCallback === 'function') && successCallback(this.getRaDec());
@@ -910,9 +911,9 @@ export let Aladin = (function () {
             return radec;
 
         }*/
-        let radec = this.webglAPI.getCenter(); // This is given in the frame of the view
+        let radec = this.wasm.getCenter(); // This is given in the frame of the view
         // We must convert it to ICRSJ2000
-        const radec_j2000 = this.view.aladin.webglAPI.viewToICRSJ2000CooSys(radec[0], radec[1]);
+        const radec_j2000 = this.wasm.viewToICRSJ2000CooSys(radec[0], radec[1]);
 
         if (radec_j2000[0]<0) {
             return [radec_j2000[0] + 360.0, radec_j2000[1]];
@@ -1076,7 +1077,7 @@ export let Aladin = (function () {
         } else {
             color = rgb;
         }
-        this.webglAPI.setBackgroundColor(color);
+        this.wasm.setBackgroundColor(color);
     };
 
     // @api
@@ -1345,7 +1346,7 @@ export let Aladin = (function () {
         }
 
         try {
-            const [ra, dec] = this.view.aladin.webglAPI.screenToWorld(x, y);
+            const [ra, dec] = this.wasm.screenToWorld(x, y);
 
             if (ra < 0) {
                 return [ra + 360.0, dec];
@@ -1375,7 +1376,7 @@ export let Aladin = (function () {
         }
 
         try {
-            return this.view.aladin.webglAPI.worldToScreen(ra, dec);
+            return this.wasm.worldToScreen(ra, dec);
         } catch (e) {
             return undefined;
         }
@@ -1406,7 +1407,7 @@ export let Aladin = (function () {
             y2 = (k == 1 || k == 2) ? this.view.height - 1 : 0;
 
             for (var step = 0; step < nbSteps; step++) {
-                let radec = this.webglAPI.screenToWorld(x1 + step / nbSteps * (x2 - x1), y1 + step / nbSteps * (y2 - y1));
+                let radec = this.wasm.screenToWorld(x1 + step / nbSteps * (x2 - x1), y1 + step / nbSteps * (y2 - y1));
                 points.push(radec);
             }
         }
@@ -1456,6 +1457,8 @@ export let Aladin = (function () {
 /////// Aladin Lite API ///////
 ///////////////////////////////
 let A = {};
+console.log("jkjkjkj")
+
 //// New API ////
 // For developers using Aladin lite: all objects should be created through the API, 
 // rather than creating directly the corresponding JS objects
@@ -1678,7 +1681,7 @@ Aladin.prototype.displayJPG = Aladin.prototype.displayPNG = function (url, optio
                 executeDefaultSuccessAction = successCallback(meta.ra, meta.dec, meta.fov);
             }
             if (executeDefaultSuccessAction === true) {
-                self.webglAPI.setCenter(meta.ra, meta.dec);
+                self.wasm.setCenter(meta.ra, meta.dec);
                 self.setFoV(meta.fov);
             }
 
@@ -1812,7 +1815,7 @@ A.init = (async () => {
     // Check for webgl2 support
     if (isWebGL2Supported) {
         const module = await import('./../../pkg-webgl2');
-        Aladin.wasmLibs.webgl = module;
+        Aladin.wasmLibs.core = module;
     } else {
         // WebGL1 not supported
         // According to caniuse, https://caniuse.com/webgl2, webgl2 is supported by 89% of users
diff --git a/src/js/AladinUtils.js b/src/js/AladinUtils.js
index 0cd315ed..740af328 100644
--- a/src/js/AladinUtils.js
+++ b/src/js/AladinUtils.js
@@ -93,19 +93,7 @@ export let AladinUtils = (function() {
             return AladinUtils.xyToView(xy.X, xy.Y, width, height, largestDim, zoomFactor, false);
         },*/
         radecToViewXy: function(ra, dec, view) {
-            //var xy;
-            //if (currentFrame.system != CooFrameEnum.SYSTEMS.J2000) {
-            //    var lonlat = CooConversion.J2000ToGalactic([ra, dec]);
-            //    xy = view.aladin.webglAPI.worldToScreen(lonlat[0], lonlat[1]);
-            //}
-            //else {
-            //var lonlat = CooConversion.J2000ToGalactic([ra, dec]);
-            let xy = view.aladin.webglAPI.worldToScreen(ra, dec);
-            //}
-            //if (!xy) {
-            //    return null;
-            //}
-
+            let xy = view.wasm.worldToScreen(ra, dec);
             return xy;
         },
     	
diff --git a/src/js/Catalog.js b/src/js/Catalog.js
index e3159036..033e7c51 100644
--- a/src/js/Catalog.js
+++ b/src/js/Catalog.js
@@ -548,7 +548,7 @@ export let Catalog = (function() {
             return;
         }*/
         var sourceSize = catalogInstance.sourceSize;
-        //console.log('COMPUTE', aladin.webglAPI.worldToScreen(s.ra, s.dec));
+        //console.log('COMPUTE', aladin.wasm.worldToScreen(s.ra, s.dec));
         //console.log(sources)
         let sourcesInView = [];
 
@@ -600,7 +600,7 @@ export let Catalog = (function() {
             return false;
         }
         var sourceSize = catalogInstance.sourceSize;
-        //console.log('COMPUTE', aladin.webglAPI.worldToScreen(s.ra, s.dec));
+        //console.log('COMPUTE', aladin.wasm.worldToScreen(s.ra, s.dec));
         var xy = AladinUtils.radecToViewXy(s.ra, s.dec, catalogInstance.view);
 
         if (xy) {
diff --git a/src/js/Ellipse.js b/src/js/Ellipse.js
index bf7bc034..5f4f2931 100644
--- a/src/js/Ellipse.js
+++ b/src/js/Ellipse.js
@@ -207,8 +207,8 @@ export let Ellipse = (function() {
         let toNorth = [this.centerRaDec[0], this.centerRaDec[1] + 1e-3];
 
         // 2. Project it to the screen
-        let originScreen = this.overlay.view.aladin.webglAPI.worldToScreen(origin[0], origin[1]);
-        let toNorthScreen = this.overlay.view.aladin.webglAPI.worldToScreen(toNorth[0], toNorth[1]);
+        let originScreen = this.overlay.view.wasm.worldToScreen(origin[0], origin[1]);
+        let toNorthScreen = this.overlay.view.wasm.worldToScreen(toNorth[0], toNorth[1]);
 
         // 3. normalize this vector
         let toNorthVec = [toNorthScreen[0] - originScreen[0], toNorthScreen[1] - originScreen[1]];
diff --git a/src/js/ImageFITS.js b/src/js/ImageFITS.js
index d05b07e1..a99eaa90 100644
--- a/src/js/ImageFITS.js
+++ b/src/js/ImageFITS.js
@@ -35,6 +35,8 @@ export let ImageFITS = (function () {
 
     function ImageFITS(url, name, view, options, successCallback = undefined, errorCallback = undefined) {
         this.view = view;
+        this.wasm = view.wasm;
+
         // Name of the layer
         this.layer = null;
         this.added = false;
@@ -59,23 +61,11 @@ export let ImageFITS = (function () {
         updateMetadata(self);
         ImageLayer.update(self);
 
-        // Return a promise that take the layer name as parameter
-        // and when resolved, will return the ImageFITS object
-        self.query = (async () => {
-            const init = {
-                method: "GET",
-                headers: {
-                    Accept: 'application/fits'
-                }
-            };
+        this.query = Promise.resolve(self);
+    }
 
-            return fetch(this.url, init)
-                .then((resp) => resp.arrayBuffer())
-                .then((arrayBuffer) => {
-                    self.arrayBuffer = new Uint8Array(arrayBuffer);
-                    return self;
-                });
-        })();
+    ImageFITS.prototype.isReady = function() {
+        return this.added;
     }
 
     // @api
@@ -151,8 +141,8 @@ export let ImageFITS = (function () {
         try {
             if (self.added) {
                 const metadata = self.metadata();
-                self.view.aladin.webglAPI.setImageMetadata(self.layer, metadata);
-                // once the meta have been well parsed, we can set the meta 
+                self.wasm.setImageMetadata(self.layer, metadata);
+
                 ALEvent.HIPS_LAYER_CHANGED.dispatchedTo(self.view.aladinDiv, { layer: self });
             }
         } catch (e) {
@@ -165,32 +155,28 @@ export let ImageFITS = (function () {
         this.layer = layer;
 
         let self = this;
-        try {
-            const { ra, dec, fov } = this.view.aladin.webglAPI.addImageFITS({
-                layer: self.layer,
-                url: self.url.toString(),
-                meta: self.metadata()
-            },
-                self.arrayBuffer,
-            );
+        self.wasm.addImageFITS({
+            layer: self.layer,
+            url: self.url.toString(),
+            meta: self.metadata()
+        }).then(({ra, dec, fov}) => {
+            console.log("success")
+            self.added = true;
 
-            this.ra = ra;
-            this.dec = dec;
-            this.fov = fov;
-
-            this.added = true;
-
-            // execute the callback if there are
-            if (this.successCallback) {
-                this.successCallback(self.ra, self.dec, self.fov, self);
+            if (self.successCallback) {
+                self.successCallback(ra, dec, fov, this);
             }
-        } catch (e) {
-            if (this.errorCallback) {
-                this.errorCallback();
+        }).catch((e) => {
+            console.error(e)
+            if (self.errorCallback) {
+                self.errorCallback()
             }
 
-            throw e;
-        }
+            // This error result from a promise
+            // If I throw it, it will not be catched because
+            // it is run async
+            self.view.removeImageLayer(layer)
+        });
     };
 
     // @api
@@ -225,7 +211,7 @@ export let ImageFITS = (function () {
 
     // @api
     ImageFITS.prototype.readPixel = function (x, y) {
-        return this.view.aladin.webglAPI.readPixel(x, y, this.layer);
+        return this.wasm.readPixel(x, y, this.layer);
     };
 
     return ImageFITS;
diff --git a/src/js/ImageSurvey.js b/src/js/ImageSurvey.js
index 4fb4393b..444bc96f 100644
--- a/src/js/ImageSurvey.js
+++ b/src/js/ImageSurvey.js
@@ -137,6 +137,7 @@ export let ImageSurvey = (function () {
     function ImageSurvey(id, name, url, view, options) {
         // A reference to the view
         this.view = view;
+        this.wasm = view.wasm;
         this.added = false;
         this.id = id;
         this.name = name;
@@ -325,13 +326,17 @@ export let ImageSurvey = (function () {
         })();
     };
 
+    ImageSurvey.prototype.isReady = function() {
+        return this.added;
+    }
+
     ImageSurvey.prototype.setUrl = function (url) {
         if (this.properties.url !== url) {
             console.info("Change url of ", this.id, " from ", this.properties.url, " to ", url)
 
             // If added to the backend, then we need to tell it the url has changed
             if (this.added) {
-                this.view.aladin.webglAPI.setHiPSUrl(this.properties.url, url);
+                this.wasm.setHiPSUrl(this.properties.url, url);
             }
 
             this.properties.url = url;
@@ -460,7 +465,7 @@ export let ImageSurvey = (function () {
         try {
             if (self.added) {
                 const metadata = self.metadata();
-                self.view.aladin.webglAPI.setImageMetadata(self.layer, metadata);
+                self.wasm.setImageMetadata(self.layer, metadata);
                 // once the meta have been well parsed, we can set the meta 
                 ALEvent.HIPS_LAYER_CHANGED.dispatchedTo(self.view.aladinDiv, { layer: self });
             }
@@ -477,7 +482,7 @@ export let ImageSurvey = (function () {
             properties: this.properties,
             meta: this.metadata(),
         })*/
-        this.view.aladin.webglAPI.addImageSurvey({
+        this.wasm.addImageSurvey({
             layer: this.layer,
             properties: this.properties,
             meta: this.metadata(),
@@ -518,7 +523,7 @@ export let ImageSurvey = (function () {
 
     // @api
     ImageSurvey.prototype.readPixel = function (x, y) {
-        return this.view.aladin.webglAPI.readPixel(x, y, this.layer);
+        return this.wasm.readPixel(x, y, this.layer);
     };
 
     ImageSurvey.DEFAULT_SURVEY_ID = "P/DSS2/color";
diff --git a/src/js/MOC.js b/src/js/MOC.js
index 6accabfb..5b03aa2a 100644
--- a/src/js/MOC.js
+++ b/src/js/MOC.js
@@ -71,13 +71,13 @@ export let MOC = (function() {
         let self = this;
 
         this.view = view;
-        this.mocParams = new Aladin.wasmLibs.webgl.MOC(this.uuid, this.opacity, this.lineWidth, this.isShowing, this.color, this.adaptativeDisplay);
+        this.mocParams = new Aladin.wasmLibs.core.MOC(this.uuid, this.opacity, this.lineWidth, this.isShowing, this.color, this.adaptativeDisplay);
 
         if (this.dataURL) {
             this.promiseFetchData
                 .then((arrayBuffer) => {
                     // Add the fetched moc to the rust backend
-                    self.view.aladin.webglAPI.addFITSMoc(self.mocParams, new Uint8Array(arrayBuffer));
+                    self.view.wasm.addFITSMoc(self.mocParams, new Uint8Array(arrayBuffer));
                     self.ready = true;
 
                     if (self.successCallback) {
@@ -85,7 +85,7 @@ export let MOC = (function() {
                     }
 
                     // Cache the sky fraction
-                    self.skyFrac = self.view.aladin.webglAPI.mocSkyFraction(this.mocParams);
+                    self.skyFrac = self.view.wasm.mocSkyFraction(this.mocParams);
 
                     // Add it to the view
                     self.view.mocs.push(self);
@@ -97,11 +97,11 @@ export let MOC = (function() {
                     self.view.requestRedraw();
                 })
         } else if (this.dataFromJSON) {
-            self.view.aladin.webglAPI.addJSONMoc(self.mocParams, self.dataJSON);
+            self.view.wasm.addJSONMoc(self.mocParams, self.dataJSON);
             self.ready = true;
 
             // Cache the sky fraction
-            self.skyFrac = self.view.aladin.webglAPI.mocSkyFraction(self.mocParams);
+            self.skyFrac = self.view.wasm.mocSkyFraction(self.mocParams);
 
             // Add it to the view
             self.view.mocs.push(self);
@@ -117,8 +117,8 @@ export let MOC = (function() {
     MOC.prototype.reportChange = function() {
         if (this.view) {
             // update the new moc params to the backend
-            this.mocParams = new Aladin.wasmLibs.webgl.MOC(this.uuid, this.opacity, this.lineWidth, this.isShowing, this.color, this.adaptativeDisplay);
-            this.view.aladin.webglAPI.setMocParams(this.mocParams);
+            this.mocParams = new Aladin.wasmLibs.core.MOC(this.uuid, this.opacity, this.lineWidth, this.isShowing, this.color, this.adaptativeDisplay);
+            this.view.wasm.setMocParams(this.mocParams);
             this.view.requestRedraw();
         }
     };
@@ -126,7 +126,7 @@ export let MOC = (function() {
     MOC.prototype.delete = function() {
         if (this.view) {
             // update the new moc params to the backend
-            this.view.aladin.webglAPI.removeMoc(this.mocParams);
+            this.view.wasm.removeMoc(this.mocParams);
             this.view.requestRedraw();
         }
     };
@@ -156,7 +156,7 @@ export let MOC = (function() {
         }
 
         // update the new moc params to the backend
-        return this.view.aladin.webglAPI.mocContains(this.mocParams, ra, dec);
+        return this.view.wasm.mocContains(this.mocParams, ra, dec);
     };
 
     return MOC;
diff --git a/src/js/View.js b/src/js/View.js
index cdd3a485..3dbd10af 100644
--- a/src/js/View.js
+++ b/src/js/View.js
@@ -64,11 +64,12 @@ export let View = (function () {
         try {
             // Start our Rust application. You can find `WebClient` in `src/lib.rs`
             // The Rust part should also create a new WebGL2 or WebGL1 context depending on the WebGL2 brower support.
-            const webglCtx = new WebGLCtx(Aladin.wasmLibs.webgl, this.aladinDiv.id);
-            this.aladin.webglAPI = webglCtx.webclient;
+            const webglCtx = new WebGLCtx(Aladin.wasmLibs.core, this.aladinDiv.id);
+            this.aladin.wasm = webglCtx.webclient;
+            this.wasm = this.aladin.wasm;
 
             // Retrieve all the possible colormaps
-            ColorCfg.COLORMAPS = this.aladin.webglAPI.getAvailableColormapList();
+            ColorCfg.COLORMAPS = this.wasm.getAvailableColormapList();
         } catch (e) {
             // For browsers not supporting WebGL2:
             // 1. Print the original exception message in the console
@@ -82,7 +83,7 @@ export let View = (function () {
             const files = Utils.getDroppedFilesHandler(event);
 
             files.forEach((file) => {
-                const reader = new FileReader();
+                /*const reader = new FileReader();
                 reader.readAsArrayBuffer(file);
 
                 reader.addEventListener("load", () => {
@@ -100,7 +101,17 @@ export let View = (function () {
 
                 reader.addEventListener('error', (event) => {
                     console.error(event.target.error);
-                });
+                });*/
+
+                const url = URL.createObjectURL(file);
+
+                try {
+                    const imageFITS = self.aladin.createImageFITS(url, file.name, undefined, undefined, undefined);
+                    self.setOverlayImageLayer(imageFITS, Utils.uuidv4())
+                } catch(e) {
+                    console.error("Only valid fits files supported (i.e. containig a WCS)", e)
+                    throw e;
+                }
             })
         };
 
@@ -120,11 +131,8 @@ export let View = (function () {
         lon = lat = 0;
         this.projection = ProjectionEnum.SIN;
 
-        //this.zoomLevel = 0;
         // Prev time of the last frame
-        this.prev = 0;
-        //this.zoomFactor = this.computeZoomFactor(this.zoomLevel);
-        this.zoomFactor = this.aladin.webglAPI.getClipZoomFactor();
+        this.zoomFactor = this.wasm.getClipZoomFactor();
 
         this.viewCenter = { lon: lon, lat: lat }; // position of center of view
 
@@ -292,7 +300,7 @@ export let View = (function () {
         //this.aladinDiv.style.width = this.width + "px";
         //this.aladinDiv.style.height = this.height + "px";
 
-        this.aladin.webglAPI.resize(this.width, this.height);
+        this.wasm.resize(this.width, this.height);
 
         this.catalogCtx = this.catalogCanvas.getContext("2d");
 
@@ -372,7 +380,7 @@ export let View = (function () {
             .then((img) => {
                 imgType = imgType || "image/png";
                 
-                const canvas = this.aladin.webglAPI.canvas();
+                const canvas = this.wasm.canvas();
 
                 var c = document.createElement('canvas');
                 let dpi = window.devicePixelRatio;
@@ -411,8 +419,8 @@ export let View = (function () {
             var xymouse = view.imageCanvas.relMouseCoords(e);
 
             try {
-                const lonlat = view.aladin.webglAPI.screenToWorld(xymouse.x, xymouse.y);
-                var radec = view.aladin.webglAPI.viewToICRSJ2000CooSys(lonlat[0], lonlat[1]);
+                const lonlat = view.wasm.screenToWorld(xymouse.x, xymouse.y);
+                var radec = view.wasm.viewToICRSJ2000CooSys(lonlat[0], lonlat[1]);
                 view.pointTo(radec[0], radec[1], { forceAnimation: true });
             }
             catch (err) {
@@ -467,11 +475,11 @@ export let View = (function () {
                 view.pinchZoomParameters.isPinching = true;
                 //var fov = view.aladin.getFov();
                 //view.pinchZoomParameters.initialFov = Math.max(fov[0], fov[1]);
-                var fov = view.aladin.webglAPI.getFieldOfView();
+                var fov = view.wasm.getFieldOfView();
                 view.pinchZoomParameters.initialFov = fov;
                 view.pinchZoomParameters.initialDistance = Math.sqrt(Math.pow(e.originalEvent.targetTouches[0].clientX - e.originalEvent.targetTouches[1].clientX, 2) + Math.pow(e.originalEvent.targetTouches[0].clientY - e.originalEvent.targetTouches[1].clientY, 2));
 
-                view.fingersRotationParameters.initialViewAngleFromCenter = view.aladin.webglAPI.getRotationAroundCenter();
+                view.fingersRotationParameters.initialViewAngleFromCenter = view.wasm.getRotationAroundCenter();
                 view.fingersRotationParameters.initialFingerAngle = Math.atan2(e.originalEvent.targetTouches[1].clientY - e.originalEvent.targetTouches[0].clientY, e.originalEvent.targetTouches[1].clientX - e.originalEvent.targetTouches[0].clientX) * 180.0 / Math.PI;
 
                 return;
@@ -488,7 +496,7 @@ export let View = (function () {
                 view.selectStartCoo = { x: view.dragx, y: view.dragy };
             }
 
-            view.aladin.webglAPI.pressLeftMouseButton(view.dragx, view.dragy);
+            view.wasm.pressLeftMouseButton(view.dragx, view.dragy);
             return false; // to disable text selection
         });
 
@@ -569,7 +577,7 @@ export let View = (function () {
                 let radec = view.aladin.pix2world(xymouse.x, xymouse.y);
 
                 // Convert from view to ICRSJ2000
-                radec = view.aladin.webglAPI.viewToICRSJ2000CooSys(radec[0], radec[1]);
+                radec = view.wasm.viewToICRSJ2000CooSys(radec[0], radec[1]);
 
                 view.setMode(View.PAN);
                 view.setCursor('wait');
@@ -643,7 +651,7 @@ export let View = (function () {
             view.refreshProgressiveCats();
 
             //view.requestRedraw();
-            view.aladin.webglAPI.releaseLeftButtonMouse();
+            view.wasm.releaseLeftButtonMouse();
         });
         var lastHoveredObject; // save last object hovered by mouse
         var lastMouseMovePos = null;
@@ -685,14 +693,14 @@ export let View = (function () {
 
                 if (view.fingersRotationParameters.rotationInitiated) {
                     let rotation = view.fingersRotationParameters.initialViewAngleFromCenter;
-                    if (!view.aladin.webglAPI.getLongitudeReversed()) {
+                    if (!view.wasm.getLongitudeReversed()) {
                         // spatial survey case
                         rotation += fingerAngleDiff;
                     } else {
                         // planetary survey case
                         rotation -= fingerAngleDiff;
                     }
-                    view.aladin.webglAPI.setRotationAroundCenter(rotation);
+                    view.wasm.setRotationAroundCenter(rotation);
                 }
 
                 // zoom
@@ -770,10 +778,9 @@ export let View = (function () {
 
             view.realDragging = true;
 
-            //webglAPI.goFromTo(pos1[0], pos1[1], pos2[0], pos2[1]);
-            view.aladin.webglAPI.goFromTo(s1.x, s1.y, s2.x, s2.y);
-            //webglAPI.setCenter(pos2[0], pos2[1]);
-            const [ra, dec] = view.aladin.webglAPI.getCenter();
+            view.wasm.goFromTo(s1.x, s1.y, s2.x, s2.y);
+
+            const [ra, dec] = view.wasm.getCenter();
             view.viewCenter.lon = ra;
             view.viewCenter.lat = dec;
             if (view.viewCenter.lon < 0.0) {
@@ -921,10 +928,10 @@ export let View = (function () {
 
     View.prototype.updateLocation = function (mouseX, mouseY, isViewCenterPosition) {
         if (isViewCenterPosition) {
-            //const [ra, dec] = this.aladin.webglAPI.ICRSJ2000ToViewCooSys(this.viewCenter.lon, this.viewCenter.lat);
+            //const [ra, dec] = this.wasm.ICRSJ2000ToViewCooSys(this.viewCenter.lon, this.viewCenter.lat);
             this.location.update(this.viewCenter.lon, this.viewCenter.lat, this.cooFrame, true);
         } else {
-            let radec = this.aladin.webglAPI.screenToWorld(mouseX, mouseY); // This is given in the frame of the view
+            let radec = this.wasm.screenToWorld(mouseX, mouseY); // This is given in the frame of the view
             if (radec) {
                 if (radec[0] < 0) {
                     radec = [radec[0] + 360.0, radec[1]];
@@ -969,21 +976,21 @@ export let View = (function () {
 
             // Drawing code
             try {
-                this.aladin.webglAPI.update(elapsedTime);
+                this.wasm.update(elapsedTime);
             } catch (e) {
                 console.warn(e)
             }
 
             // check whether a catalog has been parsed and
             // is ready to be plot
-            /*let catReady = this.aladin.webglAPI.isCatalogLoaded();
+            /*let catReady = this.wasm.isCatalogLoaded();
             if (catReady) {
                 var callbackFn = this.aladin.callbacksByEventName['catalogReady'];
                 (typeof callbackFn === 'function') && callbackFn();
             }*/
 
             ////// 2. Draw catalogues////////
-            const isViewRendering = this.aladin.webglAPI.isRendering();
+            const isViewRendering = this.wasm.isRendering();
             if (isViewRendering || this.needRedraw) {
                 this.drawAllOverlays();
             }
@@ -1156,11 +1163,11 @@ export let View = (function () {
 
     View.prototype.getVisiblePixList = function (norder) {
         var pixList = [];
-        let centerWorldPosition = this.aladin.webglAPI.screenToWorld(this.cx, this.cy);
-        const [lon, lat] = this.aladin.webglAPI.viewToICRSJ2000CooSys(centerWorldPosition[0], centerWorldPosition[1]);
+        let centerWorldPosition = this.wasm.screenToWorld(this.cx, this.cy);
+        const [lon, lat] = this.wasm.viewToICRSJ2000CooSys(centerWorldPosition[0], centerWorldPosition[1]);
 
         var radius = this.fov * 0.5 * this.ratio;
-        this.aladin.webglAPI.queryDisc(norder, lon, lat, radius).forEach(x => pixList.push(Number(x)));
+        this.wasm.queryDisc(norder, lon, lat, radius).forEach(x => pixList.push(Number(x)));
 
         return pixList;
     };
@@ -1185,12 +1192,12 @@ export let View = (function () {
             }
             var cornersXYView = [];
             //corners = HealpixCache.corners_nest(ipix, nside);
-            corners = this.aladin.webglAPI.hpxNestedVertices(Math.log2(nside), ipix);
+            corners = this.wasm.hpxNestedVertices(Math.log2(nside), ipix);
 
             for (var k=0; k<4; k++) {
                 const lon = corners[k*2];
                 const lat = corners[k*2 + 1];
-                cornersXY[k] = this.aladin.webglAPI.worldToScreen(lon, lat);
+                cornersXY[k] = this.wasm.worldToScreen(lon, lat);
             }
 
             if (cornersXY[0] == null ||  cornersXY[1] == null  ||  cornersXY[2] == null ||  cornersXY[3] == null ) {
@@ -1257,13 +1264,13 @@ export let View = (function () {
         }
         
         return cells;*/
-        return this.aladin.webglAPI.getVisibleCells(norder);
+        return this.wasm.getVisibleCells(norder);
     };
 
     // Called for touchmove events
     // initialAccDelta must be consistent with fovDegrees here
     View.prototype.setZoom = function (fovDegrees) {
-        this.aladin.webglAPI.setFieldOfView(fovDegrees);
+        this.wasm.setFieldOfView(fovDegrees);
         this.updateZoomState();
     };
 
@@ -1303,11 +1310,11 @@ export let View = (function () {
     }
 
     View.prototype.setRotation = function(rotation) {
-        this.aladin.webglAPI.setRotationAroundCenter(rotation);
+        this.wasm.setRotationAroundCenter(rotation);
     }
 
     View.prototype.setGridConfig = function (gridCfg) {
-        this.aladin.webglAPI.setGridConfig(gridCfg);
+        this.wasm.setGridConfig(gridCfg);
 
         // send events
         if (gridCfg) {
@@ -1331,8 +1338,8 @@ export let View = (function () {
 
     View.prototype.updateZoomState = function () {
         // Get the new zoom values from the backend
-        this.zoomFactor = this.aladin.webglAPI.getClipZoomFactor();
-        let fov = this.aladin.webglAPI.getFieldOfView();
+        this.zoomFactor = this.wasm.getClipZoomFactor();
+        let fov = this.wasm.getFieldOfView();
 
         // Update the pinch zoom parameters consequently
         const si = 500000.0;
@@ -1374,7 +1381,7 @@ export let View = (function () {
      * compute and set the norder corresponding to the current view resolution
      */
     View.prototype.computeNorder = function () {
-        var norder = this.aladin.webglAPI.getNOrder();
+        var norder = this.wasm.getNOrder();
 
         this.realNorder = norder;
         // here, we force norder to 3 (otherwise, the display is "blurry" for too long when zooming in)
@@ -1476,7 +1483,7 @@ export let View = (function () {
         }
 
         // Throw an exception if either the first or the second layers are not in the stack
-        this.aladin.webglAPI.renameLayer(layer, newLayer);
+        this.wasm.renameLayer(layer, newLayer);
 
         let imageLayer = this.imageLayers.get(layer);
         imageLayer.layer = newLayer;
@@ -1499,7 +1506,7 @@ export let View = (function () {
 
     View.prototype.swapLayers = function(firstLayer, secondLayer) {
         // Throw an exception if either the first or the second layers are not in the stack
-        this.aladin.webglAPI.swapLayers(firstLayer, secondLayer);
+        this.wasm.swapLayers(firstLayer, secondLayer);
     
         // Swap in overlaylayers
         const idxFirstLayer = this.overlayLayers.findIndex(overlayLayer => overlayLayer == firstLayer);
@@ -1514,22 +1521,21 @@ export let View = (function () {
     }
 
     View.prototype.removeImageLayer = function (layer) {
-        if (layer === "base") {
-            throw 'The base layer cannot be removed';
+        // Get the survey to remove to dissociate it from the view
+        let imageLayer = this.imageLayers.get(layer);
+        // Update the backend
+        if (imageLayer.added) {
+            this.wasm.removeLayer(layer);
         }
 
-        // Update the backend
-        this.aladin.webglAPI.removeLayer(layer);
+        // Get the survey to remove to dissociate it from the view
+        imageLayer.added = false;
 
         const idxOverlaidLayer = this.overlayLayers.findIndex(overlaidLayer => overlaidLayer == layer);
         if (idxOverlaidLayer == -1) {
             // layer not found
             return;
-        }
-
-        // Get the survey to remove to dissociate it from the view
-        let imageLayer = this.imageLayers.get(layer);
-        imageLayer.added = false;
+        }   
 
         // Delete it
         this.imageLayers.delete(layer);
@@ -1539,20 +1545,31 @@ export let View = (function () {
 
         if (this.overlayLayers.length === 0) {
             this.empty = true;
-        }
-
-        // find the toppest layer
-        if (this.selectedLayer === layer) {
-            const toppestLayer = this.overlayLayers[this.overlayLayers.length - 1];
-            this.selectedLayer = toppestLayer;
+            this.selectedLayer = "base";
+        } else {
+            // find the toppest layer
+            if (this.selectedLayer === layer) {
+                const toppestLayer = this.overlayLayers[this.overlayLayers.length - 1];
+                this.selectedLayer = toppestLayer;
+            }
         }
 
         ALEvent.HIPS_LAYER_REMOVED.dispatchedTo(this.aladinDiv, { layer: layer });
+
+        // check if there are no more surveys
+        const noMoreLayersToWaitFor = this.promises.length === 0;
+        if (noMoreLayersToWaitFor && this.empty) {
+            // no promises to launch!
+            const idxServiceUrl = Math.round(Math.random());
+            const dssUrl = Aladin.DEFAULT_OPTIONS.surveyUrl[idxServiceUrl]
+    
+            this.aladin.setBaseImageLayer(dssUrl);
+        }
     };
 
     View.prototype.setHiPSUrl = function (pastUrl, newUrl) {
         try {
-            this.aladin.webglAPI.setHiPSUrl(pastUrl, newUrl);
+            this.wasm.setHiPSUrl(pastUrl, newUrl);
         } catch(e) {
             console.error(e)
         }
@@ -1666,7 +1683,7 @@ export let View = (function () {
                 break;  
         }
         // Change the projection here
-        this.aladin.webglAPI.setProjection(projectionName);
+        this.wasm.setProjection(projectionName);
         this.updateZoomState();
 
         this.requestRedraw();
@@ -1677,14 +1694,14 @@ export let View = (function () {
 
         // Set the new frame to the backend
         if (this.cooFrame.system == CooFrameEnum.SYSTEMS.GAL) {
-            this.aladin.webglAPI.setCooSystem(Aladin.wasmLibs.webgl.CooSystem.GAL);
+            this.wasm.setCooSystem(Aladin.wasmLibs.core.CooSystem.GAL);
         }
         else if (this.cooFrame.system == CooFrameEnum.SYSTEMS.J2000) {
-            this.aladin.webglAPI.setCooSystem(Aladin.wasmLibs.webgl.CooSystem.ICRSJ2000);
+            this.wasm.setCooSystem(Aladin.wasmLibs.core.CooSystem.ICRSJ2000);
         }
 
         // Get the new view center position (given in icrsj2000)
-        let [ra, dec] = this.aladin.webglAPI.getCenter();
+        let [ra, dec] = this.wasm.getCenter();
         this.viewCenter.lon = ra;
         this.viewCenter.lat = dec;
         if (this.viewCenter.lon < 0.0) {
@@ -1755,7 +1772,7 @@ export let View = (function () {
         this.location.update(this.viewCenter.lon, this.viewCenter.lat, this.cooFrame, true);
 
         // Put a javascript code here to do some animation
-        this.aladin.webglAPI.setCenter(this.viewCenter.lon, this.viewCenter.lat);
+        this.wasm.setCenter(this.viewCenter.lon, this.viewCenter.lat);
 
         this.requestRedraw();
 
diff --git a/src/js/gui/HiPSLayer.js b/src/js/gui/HiPSLayer.js
index a6be45b4..a0f7dbad 100644
--- a/src/js/gui/HiPSLayer.js
+++ b/src/js/gui/HiPSLayer.js
@@ -68,7 +68,7 @@ export class HiPSLayer {
 
         // HiPS main options div
         let cmListStr = '';
-        for (const cm of this.aladin.webglAPI.getAvailableColormapList()) {
+        for (const cm of this.aladin.wasm.getAvailableColormapList()) {
             cmListStr += '<option>' + cm + '</option>';
         }