diff --git a/pkgs/default.nix b/pkgs/default.nix
index 255a365..a7a0189 100644
--- a/pkgs/default.nix
+++ b/pkgs/default.nix
@@ -1,12 +1,15 @@
 final: prev:
 with prev.lib; let
   inherit (final) callPackage;
+  intel-decimalfp = callPackage ./intel-decimalfp {};
 in {
   override = {};
 
   athena-bccr = callPackage ./athena-bccr {vendor = "athena";};
   ibkr-tws = callPackage ./ibkr-tws {};
+  ibkr-tws-api = callPackage ./ibkr-tws-api {inherit intel-decimalfp;};
   idopte-bccr = callPackage ./athena-bccr {vendor = "idopte";};
+  inherit intel-decimalfp;
   snapborg = final.python3Packages.callPackage ./snapborg {};
   socialpredict = callPackage ./socialpredict {};
   spliit = callPackage ./spliit {};
diff --git a/pkgs/ibkr-tws-api/default.nix b/pkgs/ibkr-tws-api/default.nix
new file mode 100644
index 0000000..879c3d2
--- /dev/null
+++ b/pkgs/ibkr-tws-api/default.nix
@@ -0,0 +1,150 @@
+{
+  cmake,
+  lib,
+  fetchzip,
+  intel-decimalfp,
+  pkg-config,
+  protobuf,
+  python3Packages,
+  stdenv,
+}: let
+  version = "1044.01";
+
+  src-with-protobuf = stdenv.mkDerivation {
+    pname = "ibkr-tws-api-src";
+    inherit version;
+
+    src = fetchzip {
+      url = "https://interactivebrokers.github.io/downloads/twsapi_macunix.${version}.zip";
+      hash = "sha256-9bi2Mgp3qDHz8R2lrXEOYIeBffRKOWqKxDYecybR8Eo=";
+      stripRoot = false;
+    };
+
+    nativeBuildInputs = [
+      protobuf
+    ];
+
+    configurePhase = ''
+      runHook preConfigure
+
+      rm IBJts/source/{cppclient/client/protobufUnix/*,pythonclient/ibapi/protobuf/*}
+      protoc \
+        -IIBJts/source/proto \
+        --cpp_out=IBJts/source/cppclient/client/protobufUnix \
+        --python_out=IBJts/source/pythonclient/ibapi/protobuf \
+        IBJts/source/proto/*.proto
+
+      sed -i '/^import / { s/\(\<[A-Za-z0-9_]*[A-Za-z0-9]_pb2\)/ibapi.protobuf.\1/g }' IBJts/source/pythonclient/ibapi/protobuf/*.py
+      touch IBJts/source/pythonclient/ibapi/protobuf/__init__.py
+
+      runHook postConfigure
+    '';
+
+    installPhase = ''
+      runHook preInstall
+
+      cp -r . $out
+
+      runHook postInstall
+    '';
+  };
+
+  native-lib = stdenv.mkDerivation {
+    pname = "ibkr-tws-api-native";
+    inherit version;
+
+    src = src-with-protobuf;
+    sourceRoot = "ibkr-tws-api-src-${version}/IBJts/source/cppclient/client";
+
+    buildInputs = [
+      intel-decimalfp
+      protobuf
+    ];
+
+    postPatch = ''
+      sed -i 's/-std=c++11/-std=c++17/' makefile
+    '';
+
+    makeFlags = [
+      "LIB_DIR=${intel-decimalfp}/lib"
+      "LIB_NAME=libbid.a"
+    ];
+
+    installPhase = ''
+      runHook preInstall
+
+      mkdir -p $out/lib
+      cp -v lib*.so $out/lib
+
+      runHook postInstall
+    '';
+  };
+
+  test-client = stdenv.mkDerivation {
+    pname = "ibkr-tws-api-test-client";
+    inherit version;
+
+    src = src-with-protobuf;
+    sourceRoot = "ibkr-tws-api-src-${version}/IBJts/samples/Cpp/TestCppClient";
+
+    nativeBuildInputs = [
+      pkg-config
+    ];
+
+    buildInputs = [
+      intel-decimalfp
+      native-lib
+      protobuf
+    ];
+
+    postPatch = ''
+      sed -i "s/-std=c++11/-std=c++17/; s@-lprotobuf@$(pkg-config --libs protobuf)@" makefile
+    '';
+
+    makeFlags = [
+      "TestCppClientDynamic"
+      "LIB_DIR=${intel-decimalfp}/lib"
+      "LIB_NAME_SO=libbid.a"
+      "SOURCE_DIR=${native-lib}/lib"
+    ];
+
+    installPhase = ''
+      runHook preInstall
+
+      mkdir -p $out/bin
+      install -m755 TestCppClientDynamic $out/bin/TestCppClient
+
+      runHook postInstall
+    '';
+
+    postFixup = ''
+      patchelf --add-rpath ${native-lib}/lib $out/bin/TestCppClient
+    '';
+
+    meta = {
+      mainProgram = "TestCppClient";
+    };
+  };
+
+  py-client = {
+    buildPythonPackage,
+    protobuf,
+  }:
+    buildPythonPackage {
+      pname = "ibapi-python";
+      inherit version;
+
+      src = src-with-protobuf;
+      sourceRoot = "ibkr-tws-api-src-${version}/IBJts/source/pythonclient";
+
+      format = "setuptools";
+
+      propagatedBuildInputs = [
+        protobuf
+      ];
+    };
+in {
+  inherit test-client;
+  native = native-lib;
+  ibapi-python = python3Packages.callPackage py-client {};
+}
diff --git a/pkgs/intel-decimalfp/default.nix b/pkgs/intel-decimalfp/default.nix
new file mode 100644
index 0000000..9267b18
--- /dev/null
+++ b/pkgs/intel-decimalfp/default.nix
@@ -0,0 +1,41 @@
+{
+  fetchzip,
+  lib,
+  stdenv,
+}: let
+  version = "20U3";
+in
+  stdenv.mkDerivation {
+    pname = "intel-decimalfp";
+    inherit version;
+
+    src = fetchzip {
+      url = "https://www.netlib.org/misc/intel/IntelRDFPMathLib${version}.tar.gz";
+      hash = "sha256-m+Yp1IwVEEZIz+cMQXHhkQrrWeRDfIk9ey7nWvV+u44=";
+      stripRoot = false;
+    };
+
+    sourceRoot = "source/LIBRARY";
+
+    makeFlags = [
+      "OBJ_DIR=$(out)/lib"
+      "LIB_DIR=$(out)/lib"
+    ];
+
+    preBuild = ''
+      mkdir -p $out/lib
+      touch $out/lib/.directory_exists
+    '';
+
+    postBuild = ''
+      rm $out/lib/.directory_exists
+    '';
+
+    installPhase = ''
+      runHook preInstall
+
+      rm -f $out/lib/*.o
+
+      runHook postInstall
+    '';
+  }