diff --git a/build/README.md b/build/README.md
index 9f5653ea7..5e7de04d6 100644
--- a/build/README.md
+++ b/build/README.md
@@ -30,11 +30,15 @@ In [1]: from ctypes import CDLL, c_int, c_char_p, create_string_buffer, byref
 
 In [2]: c_dll = CDLL("libribasim", winmode=0x08)  # winmode for Windows
 
-In [3]: config_path = "ribasim.toml"
+In [3]: argument = create_string_buffer(0)
+   ...: c_dll.jl_init_with_image_handle(c_int(0), byref(argument))
+Out[3]: 1
 
-In [4]: c_dll.initialize(c_char_p(config_path.encode()))
-Out[4]: 0
+In [4]: config_path = "ribasim.toml"
 
-In [5]: c_dll.update()
+In [5]: c_dll.initialize(c_char_p(config_path.encode()))
 Out[5]: 0
+
+In [6]: c_dll.update()
+Out[6]: 0
 ```
diff --git a/build/build.jl b/build/build.jl
index 0d8d9662a..3ce4895ab 100644
--- a/build/build.jl
+++ b/build/build.jl
@@ -19,6 +19,7 @@ function (@main)(_)::Cint
     Pkg.activate(".")
 
     rm(output_dir; force = true, recursive = true)
+    cpu_target = default_app_cpu_target()
 
     image_recipe = ImageRecipe(;
         output_type = "--output-lib",
@@ -26,6 +27,7 @@ function (@main)(_)::Cint
         project = project_dir,
         add_ccallables = true,
         verbose = true,
+        cpu_target,
     )
     link_recipe = LinkRecipe(; image_recipe, outname = "build/ribasim/libribasim")
     bundle_recipe = BundleRecipe(; link_recipe, output_dir)
@@ -146,3 +148,13 @@ function add_metadata(project_dir, license_file, output_dir, git_repo, readme)
     # Override the Cargo.toml file with the git version
     set_version("build/cli/Cargo.toml", tag)
 end
+
+# TODO make the default https://github.com/JuliaLang/JuliaC.jl/issues/33
+function default_app_cpu_target()
+    Sys.ARCH === :i686 ? "pentium4;sandybridge,-xsaveopt,clone_all" :
+    Sys.ARCH === :x86_64 ?
+    "generic;sandybridge,-xsaveopt,clone_all;haswell,-rdrnd,base(1)" :
+    Sys.ARCH === :arm ? "armv7-a;armv7-a,neon;armv7-a,neon,vfp4" :
+    Sys.ARCH === :aarch64 ? "generic" :   #= is this really the best here? =#
+    Sys.ARCH === :powerpc64le ? "pwr8" : "generic"
+end
diff --git a/build/cli/src/main.rs b/build/cli/src/main.rs
index 64a1f3854..2e3a25dad 100644
--- a/build/cli/src/main.rs
+++ b/build/cli/src/main.rs
@@ -54,14 +54,23 @@ fn main() -> ExitCode {
     }
 
     let shared_lib_path = match OS {
-        "windows" => exe_dir.join("bin/libribasim.dll"),
-        "linux" => exe_dir.join("lib/libribasim.so"),
-        "macos" => exe_dir.join("lib/libribasim.dylib"),
+        "windows" => "bin/libribasim.dll",
+        "linux" => "lib/libribasim.so",
+        "macos" => "lib/libribasim.dylib",
         _ => unimplemented!("Your OS is not supported yet."),
     };
+    let full_shared_lib_path = exe_dir.join(shared_lib_path);
     unsafe {
         // Load the library
-        let lib = Library::new(shared_lib_path).unwrap();
+        let lib = Library::new(full_shared_lib_path).unwrap();
+
+        // Init Julia
+        let jl_init_with_image_file: Symbol<unsafe extern "C" fn(*const libc::c_char, *const libc::c_char) -> i32> =
+            lib.get(b"jl_init_with_image_file").unwrap();
+
+        let julia_bindir = CString::new(exe_dir.to_str().unwrap()).unwrap();
+        let image_path = CString::new(shared_lib_path).unwrap();
+        jl_init_with_image_file(julia_bindir.as_ptr(), image_path.as_ptr());
 
         // Execute
         let execute: Symbol<unsafe extern "C" fn(*const libc::c_char) -> i32> =
diff --git a/pixi.toml b/pixi.toml
index dadeb061d..e70b335b3 100644
--- a/pixi.toml
+++ b/pixi.toml
@@ -75,7 +75,7 @@ lint = { depends-on = [
     "mypy-ribasim-qgis",
 ] }
 # Build
-build = { "cmd" = "julia --project --check-bounds=yes build/build.jl", depends-on = [
+build = { "cmd" = "julia --project --check-bounds=yes build/build.jl", env = { "JULIA_CPU_TARGET" = "generic;sandybridge,-xsaveopt,clone_all;haswell,-rdrnd,base(1)" }, depends-on = [
     "generate-testmodels",
     "initialize-julia",
 ] }
diff --git a/python/ribasim_api/ribasim_api/ribasim_api.py b/python/ribasim_api/ribasim_api/ribasim_api.py
index 550ae7d57..b33766977 100644
--- a/python/ribasim_api/ribasim_api/ribasim_api.py
+++ b/python/ribasim_api/ribasim_api/ribasim_api.py
@@ -1,3 +1,6 @@
+# %%
+from ctypes import byref, c_int, create_string_buffer
+
 from xmipy import XmiWrapper
 
 
@@ -18,6 +21,13 @@ def get_constant_int(self, name: str) -> int:
                 return 1025
         raise ValueError(f"{name} does not map to an integer exposed by Ribasim")
 
+    def jl_init_with_image_handle(self) -> None:
+        argument = create_string_buffer(0)
+        self.lib.jl_init_with_image_handle(c_int(0), byref(argument))
+
+    def shutdown_julia(self) -> None:
+        self.lib.shutdown_julia(c_int(0))
+
     def update_subgrid_level(self) -> None:
         self.lib.update_subgrid_level()
 
diff --git a/python/ribasim_api/tests/conftest.py b/python/ribasim_api/tests/conftest.py
index c9685c23a..4ad2b4444 100644
--- a/python/ribasim_api/tests/conftest.py
+++ b/python/ribasim_api/tests/conftest.py
@@ -6,6 +6,7 @@
 from ribasim_api import RibasimApi
 from ribasim_testmodels import (
     basic_model,
+    basic_transient_model,
     leaky_bucket_model,
     two_basin_model,
     user_demand_model,
@@ -22,6 +23,13 @@ def libribasim_paths() -> tuple[Path, Path]:
     return lib_path, lib_folder
 
 
+@pytest.fixture(scope="session", autouse=True)
+def load_julia(libribasim_paths) -> None:
+    lib_path, lib_folder = libribasim_paths
+    libribasim = RibasimApi(lib_path, lib_folder)
+    libribasim.jl_init_with_image_handle()
+
+
 @pytest.fixture(scope="function")
 def libribasim(libribasim_paths, request) -> RibasimApi:
     lib_path, lib_folder = libribasim_paths
@@ -38,6 +46,11 @@ def basic() -> ribasim.Model:
     return basic_model()
 
 
+@pytest.fixture(scope="session")
+def basic_transient(basic) -> ribasim.Model:
+    return basic_transient_model(basic)
+
+
 @pytest.fixture(scope="session")
 def leaky_bucket() -> ribasim.Model:
     return leaky_bucket_model()