diff --git a/Cargo.toml b/Cargo.toml
index 6b87495..42989fe 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,6 +2,7 @@
 name = "zern"
 version = "0.3.0"
 edition = "2024"
+license = "BSD-2-Clause"
 
 [dependencies]
 clap = { version = "4.5.40", features = ["derive"] }
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..2e16d76
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,24 @@
+BSD 2-Clause License
+
+Copyright (c) 2025-2026, Antoni Piasecki
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/src/codegen_x86_64.rs b/src/codegen_x86_64.rs
index dd6ad99..f0555a0 100644
--- a/src/codegen_x86_64.rs
+++ b/src/codegen_x86_64.rs
@@ -315,7 +315,7 @@ _builtin_environ:
                 emit!(&mut self.output, "{}:", name.lexeme);
                 emit!(&mut self.output, "    push rbp");
                 emit!(&mut self.output, "    mov rbp, rsp");
-                emit!(&mut self.output, "    sub rsp, 256"); // TODO
+                emit!(&mut self.output, "    sub rsp, 256"); // TODO: eww
 
                 for (i, param) in params.iter().enumerate() {
                     let offset = env
@@ -639,6 +639,8 @@ _builtin_environ:
                             offset
                         );
                     }
+                    // TODO: since all zern values are 64bit large we currently cannot call
+                    // external functions that expect a non-64bit value past the 6th argument
                     let num_stack = arg_count - 6;
                     for i in 0..num_stack {
                         let arg_idx = arg_count - 1 - i;