diff --git a/pkgs/development/interpreters/python/cpython/2.7/default.nix b/pkgs/development/interpreters/python/cpython/2.7/default.nix
index ff1497a24e4..23b88b168b5 100644
--- a/pkgs/development/interpreters/python/cpython/2.7/default.nix
+++ b/pkgs/development/interpreters/python/cpython/2.7/default.nix
@@ -1,7 +1,9 @@
-{ stdenv, buildPackages, fetchurl
+{ stdenv, fetchurl, fetchpatch
 , bzip2
+, expat
+, libffi
 , gdbm
-, fetchpatch
+, db
 , ncurses
 , openssl
 , readline
@@ -10,15 +12,16 @@
 , zlib
 , callPackage
 , self
-, db
-, expat
-, libffi
 , CF, configd, coreutils
 , python-setup-hook
 # Some proprietary libs assume UCS2 unicode, especially on darwin :(
 , ucsEncoding ? 4
 # For the Python package set
 , packageOverrides ? (self: super: {})
+, buildPackages
+, sourceVersion
+, sha256
+, passthruFun
 }:
 
 assert x11Support -> tcl != null
@@ -29,16 +32,23 @@ assert x11Support -> tcl != null
 with stdenv.lib;
 
 let
-  majorVersion = "2.7";
-  minorVersion = "15";
-  minorVersionSuffix = "";
-  version = "${majorVersion}.${minorVersion}${minorVersionSuffix}";
-  libPrefix = "python${majorVersion}";
-  sitePackages = "lib/${libPrefix}/site-packages";
+  passthru = passthruFun rec {
+    inherit self sourceVersion packageOverrides;
+    implementation = "cpython";
+    libPrefix = "python${pythonVersion}";
+    executable = libPrefix;
+    pythonVersion = with sourceVersion; "${major}.${minor}";
+    sitePackages = "lib/${libPrefix}/site-packages";
+    inherit pythonForBuild;
+  } // {
+    inherit ucsEncoding;
+  };
+
+  version = with sourceVersion; "${major}.${minor}.${patch}${suffix}";
 
   src = fetchurl {
-    url = "https://www.python.org/ftp/python/${majorVersion}.${minorVersion}/Python-${version}.tar.xz";
-    sha256 = "0x2mvz9dp11wj7p5ccvmk9s0hzjk2fa1m462p395l4r6bfnb3n92";
+    url = with sourceVersion; "https://www.python.org/ftp/python/${major}.${minor}.${patch}/Python-${version}.tar.xz";
+    inherit sha256;
   };
 
   hasDistutilsCxxPatch = !(stdenv.cc.isGNU or false);
@@ -191,12 +201,11 @@ let
   # Build the basic Python interpreter without modules that have
   # external dependencies.
 
-in stdenv.mkDerivation ({
-    name = "python-${version}";
-    pythonVersion = majorVersion;
+in with passthru; stdenv.mkDerivation ({
+    pname = "python";
+    inherit version;
 
-    inherit majorVersion version src patches buildInputs nativeBuildInputs
-            preConfigure configureFlags;
+    inherit src patches buildInputs nativeBuildInputs preConfigure configureFlags;
 
     LDFLAGS = stdenv.lib.optionalString (!stdenv.isDarwin) "-lgcc_s";
     inherit (mkPaths buildInputs) C_INCLUDE_PATH LIBRARY_PATH;
@@ -215,7 +224,7 @@ in stdenv.mkDerivation ({
       ''
         # needed for some packages, especially packages that backport
         # functionality to 2.x from 3.x
-        for item in $out/lib/python${majorVersion}/test/*; do
+        for item in $out/lib/${libPrefix}/test/*; do
           if [[ "$item" != */test_support.py*
              && "$item" != */test/support
              && "$item" != */test/regrtest.py* ]]; then
@@ -224,9 +233,9 @@ in stdenv.mkDerivation ({
             echo $item
           fi
         done
-        touch $out/lib/python${majorVersion}/test/__init__.py
-        ln -s $out/lib/python${majorVersion}/pdb.py $out/bin/pdb
-        ln -s $out/lib/python${majorVersion}/pdb.py $out/bin/pdb${majorVersion}
+        touch $out/lib/${libPrefix}/test/__init__.py
+        ln -s $out/lib/${libPrefix}/pdb.py $out/bin/pdb
+        ln -s $out/lib/${libPrefix}/pdb.py $out/bin/pdb${sourceVersion.major}.${sourceVersion.minor}
         ln -s $out/share/man/man1/{python2.7.1.gz,python.1.gz}
 
         # Python on Nix is not manylinux1 compatible. https://github.com/NixOS/nixpkgs/issues/18484
@@ -249,21 +258,7 @@ in stdenv.mkDerivation ({
         cp libpython2.7.dll.a $out/lib
       '';
 
-    passthru = let
-      pythonPackages = callPackage ../../../../../top-level/python-packages.nix {
-        python = self;
-        overrides = packageOverrides;
-      };
-    in rec {
-      inherit libPrefix sitePackages x11Support hasDistutilsCxxPatch ucsEncoding;
-      executable = libPrefix;
-      buildEnv = callPackage ../../wrapper.nix { python = self; inherit (pythonPackages) requiredPythonModules; };
-      withPackages = import ../../with-packages.nix { inherit buildEnv pythonPackages;};
-      pkgs = pythonPackages;
-      isPy2 = true;
-      isPy27 = true;
-      interpreter = "${self}/bin/${executable}";
-    };
+    inherit passthru;
 
     enableParallelBuilding = true;
 
diff --git a/pkgs/development/interpreters/python/cpython/3.5/default.nix b/pkgs/development/interpreters/python/cpython/3.5/default.nix
deleted file mode 100644
index 19e9f3169c7..00000000000
--- a/pkgs/development/interpreters/python/cpython/3.5/default.nix
+++ /dev/null
@@ -1,212 +0,0 @@
-{ stdenv, fetchurl, fetchpatch
-, bzip2
-, expat
-, libffi
-, gdbm
-, lzma
-, ncurses
-, openssl
-, readline
-, sqlite
-, tcl ? null, tk ? null, tix ? null, libX11 ? null, xproto ? null, x11Support ? false
-, zlib
-, callPackage
-, self
-, CF, configd
-, python-setup-hook
-# For the Python package set
-, packageOverrides ? (self: super: {})
-}:
-
-assert x11Support -> tcl != null
-                  && tk != null
-                  && xproto != null
-                  && libX11 != null;
-
-with stdenv.lib;
-
-let
-  majorVersion = "3.5";
-  minorVersion = "6";
-  minorVersionSuffix = "";
-  version = "${majorVersion}.${minorVersion}${minorVersionSuffix}";
-  libPrefix = "python${majorVersion}";
-  sitePackages = "lib/${libPrefix}/site-packages";
-
-  buildInputs = filter (p: p != null) [
-    zlib bzip2 expat lzma libffi gdbm sqlite readline ncurses openssl ]
-    ++ optionals x11Support [ tcl tk libX11 xproto ]
-    ++ optionals stdenv.isDarwin [ CF configd ];
-
-  hasDistutilsCxxPatch = !(stdenv.cc.isGNU or false);
-
-in stdenv.mkDerivation {
-  name = "python3-${version}";
-  pythonVersion = majorVersion;
-  inherit majorVersion version;
-
-  inherit buildInputs;
-
-  src = fetchurl {
-    url = "https://www.python.org/ftp/python/${majorVersion}.${minorVersion}/Python-${version}.tar.xz";
-    sha256 = "0pqmf51zy2lzhbaj4yya2py2qr653j9152d0rg3p7wi1yl2dwp7m";
-  };
-
-  NIX_LDFLAGS = optionalString stdenv.isLinux "-lgcc_s";
-
-  # Determinism: The interpreter is patched to write null timestamps when compiling python files.
-  # This way python doesn't try to update them when we freeze timestamps in nix store.
-  DETERMINISTIC_BUILD=1;
-  # Determinism: We fix the hashes of str, bytes and datetime objects.
-  PYTHONHASHSEED=0;
-
-  prePatch = optionalString stdenv.isDarwin ''
-    substituteInPlace configure --replace '`/usr/bin/arch`' '"i386"'
-    substituteInPlace configure --replace '-Wl,-stack_size,1000000' ' '
-  '';
-
-  patches = [
-    ./no-ldconfig.patch
-    ./ld_library_path.patch
-  ] ++ optionals stdenv.isDarwin [
-    # Fix for https://bugs.python.org/issue24658
-    (fetchpatch {
-      url = "https://bugs.python.org/file45178/issue24658-3-3.6.diff";
-      sha256 = "1x060hs80nl34mcl2ji2i7l4shxkmxwgq8h8lcmav8rjqqz1nb4a";
-    })
-  ] ++ optionals (x11Support && stdenv.isDarwin) [
-    ./use-correct-tcl-tk-on-darwin.patch
-  ] ++ optionals hasDistutilsCxxPatch [
-    # Fix for http://bugs.python.org/issue1222585
-    # Upstream distutils is calling C compiler to compile C++ code, which
-    # only works for GCC and Apple Clang. This makes distutils to call C++
-    # compiler when needed.
-    (fetchpatch {
-      url = "https://bugs.python.org/file47046/python-3.x-distutils-C++.patch";
-      sha256 = "0dgdn9k2kmw4wh90vdnjcrnn97ylxgx7mbn9l87fwz6j501jqvk8";
-      extraPrefix = "";
-    })
-  ];
-
-  postPatch = ''
-    # Determinism
-    substituteInPlace "Lib/py_compile.py" --replace "source_stats['mtime']" "(1 if 'DETERMINISTIC_BUILD' in os.environ else source_stats['mtime'])"
-    # Determinism. This is done unconditionally
-    substituteInPlace "Lib/importlib/_bootstrap_external.py" --replace "source_mtime = int(st['mtime'])" "source_mtime = 1"
-  '' + optionalString (x11Support && (tix != null)) ''
-    substituteInPlace "Lib/tkinter/tix.py" --replace "os.environ.get('TIX_LIBRARY')" "os.environ.get('TIX_LIBRARY') or '${tix}/lib'"
-  '';
-
-  CPPFLAGS="${concatStringsSep " " (map (p: "-I${getDev p}/include") buildInputs)}";
-  LDFLAGS="${concatStringsSep " " (map (p: "-L${getLib p}/lib") buildInputs)}";
-  LIBS="${optionalString (!stdenv.isDarwin) "-lcrypt"} ${optionalString (ncurses != null) "-lncurses"}";
-
-  configureFlags = [
-    "--enable-shared"
-    "--with-threads"
-    "--without-ensurepip"
-    "--with-system-expat"
-    "--with-system-ffi"
-  ]
-    # Never even try to use lchmod on linux,
-    # don't rely on detecting glibc-isms.
-  ++ optional stdenv.hostPlatform.isLinux "ac_cv_func_lchmod=no";
-
-  preConfigure = ''
-    for i in /usr /sw /opt /pkg; do	# improve purity
-      substituteInPlace ./setup.py --replace $i /no-such-path
-    done
-    ${optionalString stdenv.isDarwin ''
-       export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -msse2"
-       export MACOSX_DEPLOYMENT_TARGET=10.6
-     ''
-     + optionalString stdenv.hostPlatform.isMusl ''
-      export NIX_CFLAGS_COMPILE+=" -DTHREAD_STACK_SIZE=0x100000"
-     ''}
-  '';
-
-  setupHook = python-setup-hook sitePackages;
-
-  postInstall = ''
-    # needed for some packages, especially packages that backport functionality
-    # to 2.x from 3.x
-    for item in $out/lib/python${majorVersion}/test/*; do
-      if [[ "$item" != */test_support.py*
-         && "$item" != */test/support
-         && "$item" != */test/libregrtest
-         && "$item" != */test/regrtest.py* ]]; then
-        rm -rf "$item"
-      else
-        echo $item
-      fi
-    done
-    touch $out/lib/python${majorVersion}/test/__init__.py
-
-    ln -s "$out/include/python${majorVersion}m" "$out/include/python${majorVersion}"
-
-    # Python on Nix is not manylinux1 compatible. https://github.com/NixOS/nixpkgs/issues/18484
-    echo "manylinux1_compatible=False" >> $out/lib/${libPrefix}/_manylinux.py
-
-    # Determinism: Windows installers were not deterministic.
-    # We're also not interested in building Windows installers.
-    find "$out" -name 'wininst*.exe' | xargs -r rm -f
-
-    # Use Python3 as default python
-    ln -s "$out/bin/idle3" "$out/bin/idle"
-    ln -s "$out/bin/pydoc3" "$out/bin/pydoc"
-    ln -s "$out/bin/python3" "$out/bin/python"
-    ln -s "$out/bin/python3-config" "$out/bin/python-config"
-    ln -s "$out/lib/pkgconfig/python3.pc" "$out/lib/pkgconfig/python.pc"
-
-    # Get rid of retained dependencies on -dev packages, and remove
-    # some $TMPDIR references to improve binary reproducibility.
-    # Note that the .pyc file of _sysconfigdata.py should be regenerated!
-    for i in $out/lib/python${majorVersion}/_sysconfigdata.py $out/lib/python${majorVersion}/config-${majorVersion}m/Makefile; do
-      sed -i $i -e "s|-I/nix/store/[^ ']*||g" -e "s|-L/nix/store/[^ ']*||g" -e "s|$TMPDIR|/no-such-path|g"
-    done
-
-    # Determinism: rebuild all bytecode
-    # We exclude lib2to3 because that's Python 2 code which fails
-    # We rebuild three times, once for each optimization level
-    find $out -name "*.py" | $out/bin/python -m compileall -q -f -x "lib2to3" -i -
-    find $out -name "*.py" | $out/bin/python -O -m compileall -q -f -x "lib2to3" -i -
-    find $out -name "*.py" | $out/bin/python -OO -m compileall -q -f -x "lib2to3" -i -
-  '';
-
-  passthru = let
-    pythonPackages = callPackage ../../../../../top-level/python-packages.nix {
-      python = self;
-      overrides = packageOverrides;
-    };
-  in rec {
-    inherit libPrefix sitePackages x11Support hasDistutilsCxxPatch;
-    executable = "${libPrefix}m";
-    buildEnv = callPackage ../../wrapper.nix { python = self; inherit (pythonPackages) requiredPythonModules; };
-    withPackages = import ../../with-packages.nix { inherit buildEnv pythonPackages;};
-    pkgs = pythonPackages;
-    isPy3 = true;
-    isPy35 = true;
-    interpreter = "${self}/bin/${executable}";
-  };
-
-  enableParallelBuilding = true;
-
-  doCheck = false; # expensive, and fails
-
-  meta = {
-    homepage = http://python.org;
-    description = "A high-level dynamically-typed programming language";
-    longDescription = ''
-      Python is a remarkably powerful dynamic programming language that
-      is used in a wide variety of application domains. Some of its key
-      distinguishing features include: clear, readable syntax; strong
-      introspection capabilities; intuitive object orientation; natural
-      expression of procedural code; full modularity, supporting
-      hierarchical packages; exception-based error handling; and very
-      high level dynamic data types.
-    '';
-    license = licenses.psfl;
-    platforms = with platforms; linux ++ darwin;
-    maintainers = with maintainers; [ fridh ];
-  };
-}
diff --git a/pkgs/development/interpreters/python/cpython/3.6/default.nix b/pkgs/development/interpreters/python/cpython/3.6/default.nix
deleted file mode 100644
index a36965a7801..00000000000
--- a/pkgs/development/interpreters/python/cpython/3.6/default.nix
+++ /dev/null
@@ -1,228 +0,0 @@
-{ stdenv, fetchurl, fetchpatch, buildPackages
-, bzip2
-, expat
-, libffi
-, gdbm
-, lzma
-, ncurses
-, openssl
-, readline
-, sqlite
-, tcl ? null, tk ? null, tix ? null, libX11 ? null, xproto ? null, x11Support ? false
-, zlib
-, callPackage
-, self
-, CF, configd
-, python-setup-hook
-# For the Python package set
-, packageOverrides ? (self: super: {})
-}:
-
-assert x11Support -> tcl != null
-                  && tk != null
-                  && xproto != null
-                  && libX11 != null;
-with stdenv.lib;
-
-let
-  majorVersion = "3.6";
-  minorVersion = "8";
-  minorVersionSuffix = "";
-  version = "${majorVersion}.${minorVersion}${minorVersionSuffix}";
-  libPrefix = "python${majorVersion}";
-  sitePackages = "lib/${libPrefix}/site-packages";
-
-  buildInputs = filter (p: p != null) [
-    zlib bzip2 expat lzma libffi gdbm sqlite readline ncurses openssl ]
-    ++ optionals x11Support [ tcl tk libX11 xproto ]
-    ++ optionals stdenv.isDarwin [ CF configd ];
-
-  nativeBuildInputs =
-    optional (stdenv.hostPlatform != stdenv.buildPlatform) buildPackages.python3;
-
-  hasDistutilsCxxPatch = !(stdenv.cc.isGNU or false);
-
-in stdenv.mkDerivation {
-  name = "python3-${version}";
-  pythonVersion = majorVersion;
-  inherit majorVersion version;
-
-  inherit buildInputs nativeBuildInputs;
-
-  src = fetchurl {
-    url = "https://www.python.org/ftp/python/${majorVersion}.${minorVersion}/Python-${version}.tar.xz";
-    sha256 = "14qi6n5gpcjnwy165wi9hkfcmbadc95ny6bxxldknxwmx50n4i1m";
-  };
-
-  NIX_LDFLAGS = optionalString stdenv.isLinux "-lgcc_s";
-
-  # Determinism: The interpreter is patched to write null timestamps when compiling python files.
-  # This way python doesn't try to update them when we freeze timestamps in nix store.
-  DETERMINISTIC_BUILD=1;
-  # Determinism: We fix the hashes of str, bytes and datetime objects.
-  PYTHONHASHSEED=0;
-
-  prePatch = optionalString stdenv.isDarwin ''
-    substituteInPlace configure --replace '`/usr/bin/arch`' '"i386"'
-    substituteInPlace configure --replace '-Wl,-stack_size,1000000' ' '
-  '';
-
-  patches = [
-    ./no-ldconfig.patch
-  ] ++ optionals (x11Support && stdenv.isDarwin) [
-    ./use-correct-tcl-tk-on-darwin.patch
-  ] ++ optionals hasDistutilsCxxPatch [
-    # Fix for http://bugs.python.org/issue1222585
-    # Upstream distutils is calling C compiler to compile C++ code, which
-    # only works for GCC and Apple Clang. This makes distutils to call C++
-    # compiler when needed.
-    (fetchpatch {
-      url = "https://bugs.python.org/file48016/python-3.x-distutils-C++.patch";
-      sha256 = "1h18lnpx539h5lfxyk379dxwr8m2raigcjixkf133l4xy3f4bzi2";
-    })
-  ];
-
-  postPatch = ''
-    # Determinism
-    substituteInPlace "Lib/py_compile.py" --replace "source_stats['mtime']" "(1 if 'DETERMINISTIC_BUILD' in os.environ else source_stats['mtime'])"
-    # Determinism. This is done unconditionally
-    substituteInPlace "Lib/importlib/_bootstrap_external.py" --replace "source_mtime = int(st['mtime'])" "source_mtime = 1"
-  '' + optionalString (x11Support && (tix != null)) ''
-    substituteInPlace "Lib/tkinter/tix.py" --replace "os.environ.get('TIX_LIBRARY')" "os.environ.get('TIX_LIBRARY') or '${tix}/lib'"
-  '';
-
-  CPPFLAGS="${concatStringsSep " " (map (p: "-I${getDev p}/include") buildInputs)}";
-  LDFLAGS="${concatStringsSep " " (map (p: "-L${getLib p}/lib") buildInputs)}";
-  LIBS="${optionalString (!stdenv.isDarwin) "-lcrypt"} ${optionalString (ncurses != null) "-lncurses"}";
-
-  configureFlags = [
-    "--enable-shared"
-    "--with-threads"
-    "--without-ensurepip"
-    "--with-system-expat"
-    "--with-system-ffi"
-  ] ++ optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
-    "ac_cv_buggy_getaddrinfo=no"
-    # Assume little-endian IEEE 754 floating point when cross compiling
-    "ac_cv_little_endian_double=yes"
-    "ac_cv_big_endian_double=no"
-    "ac_cv_mixed_endian_double=no"
-    "ac_cv_x87_double_rounding=yes"
-    "ac_cv_tanh_preserves_zero_sign=yes"
-    # Generally assume that things are present and work
-    "ac_cv_posix_semaphores_enabled=yes"
-    "ac_cv_broken_sem_getvalue=no"
-    "ac_cv_wchar_t_signed=yes"
-    "ac_cv_rshift_extends_sign=yes"
-    "ac_cv_broken_nice=no"
-    "ac_cv_broken_poll=no"
-    "ac_cv_working_tzset=yes"
-    "ac_cv_have_long_long_format=yes"
-    "ac_cv_have_size_t_format=yes"
-    "ac_cv_computed_gotos=yes"
-    "ac_cv_file__dev_ptmx=yes"
-    "ac_cv_file__dev_ptc=yes"
-  ]
-    # Never even try to use lchmod on linux,
-    # don't rely on detecting glibc-isms.
-  ++ optional stdenv.hostPlatform.isLinux "ac_cv_func_lchmod=no";
-
-  preConfigure = ''
-    for i in /usr /sw /opt /pkg; do	# improve purity
-      substituteInPlace ./setup.py --replace $i /no-such-path
-    done
-    ${optionalString stdenv.isDarwin ''
-       export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -msse2"
-       export MACOSX_DEPLOYMENT_TARGET=10.6
-     ''
-     + optionalString stdenv.hostPlatform.isMusl ''
-      export NIX_CFLAGS_COMPILE+=" -DTHREAD_STACK_SIZE=0x100000"
-     ''}
-  '';
-
-  setupHook = python-setup-hook sitePackages;
-
-  postInstall = ''
-    # needed for some packages, especially packages that backport functionality
-    # to 2.x from 3.x
-    for item in $out/lib/python${majorVersion}/test/*; do
-      if [[ "$item" != */test_support.py*
-         && "$item" != */test/support
-         && "$item" != */test/libregrtest
-         && "$item" != */test/regrtest.py* ]]; then
-        rm -rf "$item"
-      else
-        echo $item
-      fi
-    done
-    touch $out/lib/python${majorVersion}/test/__init__.py
-
-    ln -s "$out/include/python${majorVersion}m" "$out/include/python${majorVersion}"
-
-    # Python on Nix is not manylinux1 compatible. https://github.com/NixOS/nixpkgs/issues/18484
-    echo "manylinux1_compatible=False" >> $out/lib/${libPrefix}/_manylinux.py
-
-    # Determinism: Windows installers were not deterministic.
-    # We're also not interested in building Windows installers.
-    find "$out" -name 'wininst*.exe' | xargs -r rm -f
-
-    # Use Python3 as default python
-    ln -s "$out/bin/idle3" "$out/bin/idle"
-    ln -s "$out/bin/pydoc3" "$out/bin/pydoc"
-    ln -s "$out/bin/python3" "$out/bin/python"
-    ln -s "$out/bin/python3-config" "$out/bin/python-config"
-    ln -s "$out/lib/pkgconfig/python3.pc" "$out/lib/pkgconfig/python.pc"
-
-    # Get rid of retained dependencies on -dev packages, and remove
-    # some $TMPDIR references to improve binary reproducibility.
-    # Note that the .pyc file of _sysconfigdata.py should be regenerated!
-    for i in $out/lib/python${majorVersion}/_sysconfigdata*.py $out/lib/python${majorVersion}/config-${majorVersion}m*/Makefile; do
-      sed -i $i -e "s|-I/nix/store/[^ ']*||g" -e "s|-L/nix/store/[^ ']*||g" -e "s|$TMPDIR|/no-such-path|g"
-    done
-  '' + optionalString (stdenv.hostPlatform == stdenv.buildPlatform) ''
-    # Determinism: rebuild all bytecode
-    # We exclude lib2to3 because that's Python 2 code which fails
-    # We rebuild three times, once for each optimization level
-    find $out -name "*.py" | $out/bin/python -m compileall -q -f -x "lib2to3" -i -
-    find $out -name "*.py" | $out/bin/python -O -m compileall -q -f -x "lib2to3" -i -
-    find $out -name "*.py" | $out/bin/python -OO -m compileall -q -f -x "lib2to3" -i -
-  '';
-
-  passthru = let
-    pythonPackages = callPackage ../../../../../top-level/python-packages.nix {
-      python = self;
-      overrides = packageOverrides;
-    };
-  in rec {
-    inherit libPrefix sitePackages x11Support hasDistutilsCxxPatch;
-    executable = "${libPrefix}m";
-    buildEnv = callPackage ../../wrapper.nix { python = self; inherit (pythonPackages) requiredPythonModules; };
-    withPackages = import ../../with-packages.nix { inherit buildEnv pythonPackages;};
-    pkgs = pythonPackages;
-    isPy3 = true;
-    isPy36 = true;
-    is_py3k = true;  # deprecated
-    interpreter = "${self}/bin/${executable}";
-  };
-
-  enableParallelBuilding = true;
-
-  doCheck = false; # expensive, and fails
-
-  meta = {
-    homepage = http://python.org;
-    description = "A high-level dynamically-typed programming language";
-    longDescription = ''
-      Python is a remarkably powerful dynamic programming language that
-      is used in a wide variety of application domains. Some of its key
-      distinguishing features include: clear, readable syntax; strong
-      introspection capabilities; intuitive object orientation; natural
-      expression of procedural code; full modularity, supporting
-      hierarchical packages; exception-based error handling; and very
-      high level dynamic data types.
-    '';
-    license = licenses.psfl;
-    platforms = with platforms; linux ++ darwin;
-    maintainers = with maintainers; [ fridh kragniz ];
-  };
-}
diff --git a/pkgs/development/interpreters/python/cpython/3.7/default.nix b/pkgs/development/interpreters/python/cpython/default.nix
similarity index 66%
rename from pkgs/development/interpreters/python/cpython/3.7/default.nix
rename to pkgs/development/interpreters/python/cpython/default.nix
index 61ffa8ec5a4..0d1794f04fa 100644
--- a/pkgs/development/interpreters/python/cpython/3.7/default.nix
+++ b/pkgs/development/interpreters/python/cpython/default.nix
@@ -18,6 +18,9 @@
 # For the Python package set
 , packageOverrides ? (self: super: {})
 , buildPackages
+, sourceVersion
+, sha256
+, passthruFun
 }:
 
 assert x11Support -> tcl != null
@@ -27,12 +30,24 @@ assert x11Support -> tcl != null
 with stdenv.lib;
 
 let
-  majorVersion = "3.7";
-  minorVersion = "2";
-  minorVersionSuffix = "";
-  version = "${majorVersion}.${minorVersion}${minorVersionSuffix}";
-  libPrefix = "python${majorVersion}";
-  sitePackages = "lib/${libPrefix}/site-packages";
+
+  passthru = passthruFun rec {
+    inherit self sourceVersion packageOverrides;
+    implementation = "cpython";
+    libPrefix = "python${pythonVersion}";
+    executable = libPrefix;
+    pythonVersion = with sourceVersion; "${major}.${minor}";
+    sitePackages = "lib/${libPrefix}/site-packages";
+    inherit pythonForBuild;
+  };
+
+  version = with sourceVersion; "${major}.${minor}.${patch}${suffix}";
+
+  nativeBuildInputs = [
+    nukeReferences
+  ] ++ optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
+    buildPackages.stdenv.cc crossPython
+  ];
 
   buildInputs = filter (p: p != null) [
     zlib bzip2 expat lzma libffi gdbm sqlite readline ncurses openssl ]
@@ -40,44 +55,46 @@ let
     ++ optionals stdenv.isDarwin [ CF configd ];
 
   hasDistutilsCxxPatch = !(stdenv.cc.isGNU or false);
+
+  crossPython = buildPackages.${"python${sourceVersion.major}${sourceVersion.minor}"};
+
   pythonForBuild = if stdenv.hostPlatform == stdenv.buildPlatform then
     "$out/bin/python"
-  else
-    buildPackages.python37.interpreter;
-in stdenv.mkDerivation {
-  name = "python3-${version}";
-  pythonVersion = majorVersion;
-  inherit majorVersion version;
+  else crossPython.interpreter;
 
-  inherit buildInputs;
+in with passthru; stdenv.mkDerivation {
+  pname = "python3";
+  inherit version;
 
-  nativeBuildInputs = [ nukeReferences ] ++
-    optionals (stdenv.hostPlatform != stdenv.buildPlatform)
-    [ buildPackages.stdenv.cc buildPackages.python37 ];
+  inherit buildInputs nativeBuildInputs;
 
   src = fetchurl {
-    url = "https://www.python.org/ftp/python/${majorVersion}.${minorVersion}/Python-${version}.tar.xz";
-    sha256 = "1fzi9d2gibh0wzwidyckzbywsxcsbckgsl05ryxlifxia77fhgyq";
+    url = with sourceVersion; "https://www.python.org/ftp/python/${major}.${minor}.${patch}/Python-${version}.tar.xz";
+    inherit sha256;
   };
 
-  NIX_LDFLAGS = optionalString stdenv.isLinux "-lgcc_s";
-
-  # Determinism: We fix the hashes of str, bytes and datetime objects.
-  PYTHONHASHSEED=0;
-
   prePatch = optionalString stdenv.isDarwin ''
     substituteInPlace configure --replace '`/usr/bin/arch`' '"i386"'
     substituteInPlace configure --replace '-Wl,-stack_size,1000000' ' '
   '';
 
   patches = [
-    ./no-ldconfig.patch
+    # Disable the use of ldconfig in ctypes.util.find_library (since
+    # ldconfig doesn't work on NixOS), and don't use
+    # ctypes.util.find_library during the loading of the uuid module
+    # (since it will do a futile invocation of gcc (!) to find
+    # libuuid, slowing down program startup a lot).
+    (./. + "/${sourceVersion.major}.${sourceVersion.minor}/no-ldconfig.patch")
+  ] ++ optionals isPy35 [
+    # Backports support for LD_LIBRARY_PATH from 3.6
+    ./3.5/ld_library_path.patch
+  ] ++ optionals isPy37 [
     # Fix darwin build https://bugs.python.org/issue34027
     (fetchpatch {
       url = https://bugs.python.org/file47666/darwin-libutil.patch;
       sha256 = "0242gihnw3wfskl4fydp2xanpl8k5q7fj4dp7dbbqf46a4iwdzpa";
     })
-  ] ++ optionals hasDistutilsCxxPatch [
+  ] ++ optionals (isPy3k && hasDistutilsCxxPatch) [
     # Fix for http://bugs.python.org/issue1222585
     # Upstream distutils is calling C compiler to compile C++ code, which
     # only works for GCC and Apple Clang. This makes distutils to call C++
@@ -93,9 +110,12 @@ in stdenv.mkDerivation {
     substituteInPlace "Lib/tkinter/tix.py" --replace "os.environ.get('TIX_LIBRARY')" "os.environ.get('TIX_LIBRARY') or '${tix}/lib'"
   '';
 
-  CPPFLAGS="${concatStringsSep " " (map (p: "-I${getDev p}/include") buildInputs)}";
-  LDFLAGS="${concatStringsSep " " (map (p: "-L${getLib p}/lib") buildInputs)}";
-  LIBS="${optionalString (!stdenv.isDarwin) "-lcrypt"} ${optionalString (ncurses != null) "-lncurses"}";
+  CPPFLAGS = "${concatStringsSep " " (map (p: "-I${getDev p}/include") buildInputs)}";
+  LDFLAGS = "${concatStringsSep " " (map (p: "-L${getLib p}/lib") buildInputs)}";
+  LIBS = "${optionalString (!stdenv.isDarwin) "-lcrypt"} ${optionalString (ncurses != null) "-lncurses"}";
+  NIX_LDFLAGS = optionalString stdenv.isLinux "-lgcc_s";
+  # Determinism: We fix the hashes of str, bytes and datetime objects.
+  PYTHONHASHSEED=0;
 
   configureFlags = [
     "--enable-shared"
@@ -125,16 +145,25 @@ in stdenv.mkDerivation {
     "ac_cv_computed_gotos=yes"
     "ac_cv_file__dev_ptmx=yes"
     "ac_cv_file__dev_ptc=yes"
+  ] ++ optionals stdenv.hostPlatform.isLinux [
+    # Never even try to use lchmod on linux,
+    # don't rely on detecting glibc-isms.
+    "ac_cv_func_lchmod=no"
   ];
 
   preConfigure = ''
     for i in /usr /sw /opt /pkg; do	# improve purity
       substituteInPlace ./setup.py --replace $i /no-such-path
     done
-    ${optionalString stdenv.isDarwin ''
-       export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -msse2"
-       export MACOSX_DEPLOYMENT_TARGET=10.6
-     ''}
+  '' + optionalString stdenv.isDarwin ''
+    export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -msse2"
+    export MACOSX_DEPLOYMENT_TARGET=10.6
+  '' + optionalString (isPy3k && pythonOlder "3.7") ''
+    # Determinism: The interpreter is patched to write null timestamps when compiling python files.
+    # This way python does not try to update them when we freeze timestamps in nix store.
+    export DETERMINISTIC_BUILD=1;
+  '' + optionalString stdenv.hostPlatform.isMusl ''
+    export NIX_CFLAGS_COMPILE+=" -DTHREAD_STACK_SIZE=0x100000"
   '';
 
   setupHook = python-setup-hook sitePackages;
@@ -142,7 +171,7 @@ in stdenv.mkDerivation {
   postInstall = ''
     # needed for some packages, especially packages that backport functionality
     # to 2.x from 3.x
-    for item in $out/lib/python${majorVersion}/test/*; do
+    for item in $out/lib/${libPrefix}/test/*; do
       if [[ "$item" != */test_support.py*
          && "$item" != */test/support
          && "$item" != */test/libregrtest
@@ -152,9 +181,9 @@ in stdenv.mkDerivation {
         echo $item
       fi
     done
-    touch $out/lib/python${majorVersion}/test/__init__.py
+    touch $out/lib/${libPrefix}/test/__init__.py
 
-    ln -s "$out/include/python${majorVersion}m" "$out/include/python${majorVersion}"
+    ln -s "$out/include/${executable}m" "$out/include/${executable}"
 
     # Python on Nix is not manylinux1 compatible. https://github.com/NixOS/nixpkgs/issues/18484
     echo "manylinux1_compatible=False" >> $out/lib/${libPrefix}/_manylinux.py
@@ -173,14 +202,13 @@ in stdenv.mkDerivation {
     # Get rid of retained dependencies on -dev packages, and remove
     # some $TMPDIR references to improve binary reproducibility.
     # Note that the .pyc file of _sysconfigdata.py should be regenerated!
-    for i in $out/lib/python${majorVersion}/_sysconfigdata*.py $out/lib/python${majorVersion}/config-${majorVersion}m*/Makefile; do
-      sed -i $i -e "s|$TMPDIR|/no-such-path|g"
-      nuke-refs $i
+    for i in $out/lib/${libPrefix}/_sysconfigdata*.py $out/lib/${libPrefix}/config-${sourceVersion.major}${sourceVersion.minor}*/Makefile; do
+       sed -i $i -e "s|$TMPDIR|/no-such-path|g"
     done
 
     # Further get rid of references. https://github.com/NixOS/nixpkgs/issues/51668
-    find $out/lib/python*/config-*-* -type f -print -exec nuke-refs '{}' +
-    find $out/lib -name '_sysconfigdata_m*.py*' -print -exec nuke-refs '{}' +
+    find $out/lib/python*/config-* -type f -print -exec nuke-refs '{}' +
+    find $out/lib -name '_sysconfigdata*.py*' -print -exec nuke-refs '{}' +
 
     # Determinism: rebuild all bytecode
     # We exclude lib2to3 because that's Python 2 code which fails
@@ -196,22 +224,7 @@ in stdenv.mkDerivation {
   # explicitly specify in our configure flags above.
   disallowedReferences = [ openssl.dev ];
 
-  passthru = let
-    pythonPackages = callPackage ../../../../../top-level/python-packages.nix {
-      python = self;
-      overrides = packageOverrides;
-    };
-  in rec {
-    inherit libPrefix sitePackages x11Support hasDistutilsCxxPatch;
-    executable = "${libPrefix}m";
-    buildEnv = callPackage ../../wrapper.nix { python = self; inherit (pythonPackages) requiredPythonModules; };
-    withPackages = import ../../with-packages.nix { inherit buildEnv pythonPackages;};
-    pkgs = pythonPackages;
-    isPy3 = true;
-    isPy37 = true;
-    is_py3k = true;  # deprecated
-    interpreter = "${self}/bin/${executable}";
-  };
+  inherit passthru;
 
   enableParallelBuilding = true;
 
@@ -229,6 +242,6 @@ in stdenv.mkDerivation {
     '';
     license = licenses.psfl;
     platforms = with platforms; linux ++ darwin;
-    maintainers = with maintainers; [ fridh kragniz ];
+    maintainers = with maintainers; [ fridh ];
   };
 }
diff --git a/pkgs/development/interpreters/python/default.nix b/pkgs/development/interpreters/python/default.nix
new file mode 100644
index 00000000000..75226ef9a73
--- /dev/null
+++ b/pkgs/development/interpreters/python/default.nix
@@ -0,0 +1,106 @@
+{ pkgs, lib }:
+
+with pkgs;
+
+(let
+
+  # Common passthru for all Python interpreters.
+  passthruFun =
+    { implementation
+    , libPrefix
+    , executable
+    , sourceVersion
+    , pythonVersion
+    , packageOverrides
+    , sitePackages
+    , pythonForBuild
+    , self
+    }: let
+      pythonPackages = callPackage ../../../top-level/python-packages.nix {
+        python = self;
+        overrides = packageOverrides;
+      };
+    in rec {
+        sitePackages = "lib/${libPrefix}/site-packages";
+        isPy27 = pythonVersion == "2.7";
+        isPy33 = pythonVersion == "3.3"; # TODO: remove
+        isPy34 = pythonVersion == "3.4"; # TODO: remove
+        isPy35 = pythonVersion == "3.5";
+        isPy36 = pythonVersion == "3.6";
+        isPy37 = pythonVersion == "3.7";
+        isPy3k = lib.strings.substring 0 1 pythonVersion == "3";
+        isPyPy = interpreter == "pypy";
+
+        buildEnv = callPackage ./wrapper.nix { python = self; inherit (pythonPackages) requiredPythonModules; };
+        withPackages = import ./with-packages.nix { inherit buildEnv pythonPackages;};
+        pkgs = pythonPackages;
+        interpreter = "${self}/bin/${executable}";
+        inherit executable implementation libPrefix pythonVersion;
+        inherit sourceVersion;
+        pythonAtLeast = lib.versionAtLeast pythonVersion;
+        pythonOlder = lib.versionOlder pythonVersion;
+        inherit pythonForBuild;
+
+        majorVersion = pythonVersion; # Backwards compatibility. Should be dropped.
+  };
+
+in {
+
+  python27 = callPackage ./cpython/2.7 {
+    self = python27;
+    sourceVersion = {
+      major = "2";
+      minor = "7";
+      patch = "15";
+      suffix = "";
+    };
+    sha256 = "0x2mvz9dp11wj7p5ccvmk9s0hzjk2fa1m462p395l4r6bfnb3n92";
+    inherit (darwin) CF configd;
+    inherit passthruFun;
+  };
+
+  python35 = callPackage ./cpython {
+    self = python35;
+    sourceVersion = {
+      major = "3";
+      minor = "5";
+      patch = "6";
+      suffix = "";
+    };
+    sha256 = "0pqmf51zy2lzhbaj4yya2py2qr653j9152d0rg3p7wi1yl2dwp7m";
+    inherit (darwin) CF configd;
+    inherit passthruFun;
+  };
+
+  python36 = callPackage ./cpython {
+    self = python36;
+    sourceVersion = {
+      major = "3";
+      minor = "6";
+      patch = "8";
+      suffix = "";
+    };
+    sha256 = "14qi6n5gpcjnwy165wi9hkfcmbadc95ny6bxxldknxwmx50n4i1m";
+    inherit (darwin) CF configd;
+    inherit passthruFun;
+  };
+
+  python37 = callPackage ./cpython {
+    self = python37;
+    sourceVersion = {
+      major = "3";
+      minor = "7";
+      patch = "2";
+      suffix = "";
+    };
+    sha256 = "1fzi9d2gibh0wzwidyckzbywsxcsbckgsl05ryxlifxia77fhgyq";
+    inherit (darwin) CF configd;
+    inherit passthruFun;
+  };
+
+#   pypy27 = callPackage ./pypy {
+#     self = pypy27;
+#     implementation = "pypy";
+#   };
+
+})
\ No newline at end of file
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 3e7a991621c..34507b67b57 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -7953,22 +7953,8 @@ in
   python2Packages = python2.pkgs;
   python3Packages = python3.pkgs;
 
-  python27 = callPackage ../development/interpreters/python/cpython/2.7 {
-    self = python27;
-    inherit (darwin) CF configd;
-  };
-  python35 = callPackage ../development/interpreters/python/cpython/3.5 {
-    inherit (darwin) CF configd;
-    self = python35;
-  };
-  python36 = callPackage ../development/interpreters/python/cpython/3.6 {
-    inherit (darwin) CF configd;
-    self = python36;
-  };
-  python37 = callPackage ../development/interpreters/python/cpython/3.7 {
-    inherit (darwin) CF configd;
-    self = python37;
-  };
+  pythonInterpreters = callPackage ./../development/interpreters/python {};
+  inherit (pythonInterpreters) python27 python35 python36 python37;
 
   pypy27 = callPackage ../development/interpreters/python/pypy/2.7 {
     self = pypy27;
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index 8403b398ccd..e0e45ea9ecd 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -18,16 +18,7 @@ let
   packages = ( self:
 
 let
-  pythonAtLeast = versionAtLeast python.pythonVersion;
-  pythonOlder = versionOlder python.pythonVersion;
-  isPy27 = python.pythonVersion == "2.7";
-  isPy33 = python.pythonVersion == "3.3";
-  isPy34 = python.pythonVersion == "3.4";
-  isPy35 = python.pythonVersion == "3.5";
-  isPy36 = python.pythonVersion == "3.6";
-  isPy37 = python.pythonVersion == "3.7";
-  isPyPy = strings.substring 0 4 python.executable == "pypy";
-  isPy3k = strings.substring 0 1 python.pythonVersion == "3";
+  inherit (python.passthru) isPy27 isPy33 isPy34 isPy35 isPy36 isPy37 isPy3k isPyPy pythonAtLeast pythonOlder;
 
   callPackage = pkgs.newScope self;
 
@@ -130,7 +121,8 @@ let
 
 in {
 
-  inherit python bootstrapped-pip pythonAtLeast pythonOlder isPy27 isPy33 isPy34 isPy35 isPy36 isPy37 isPyPy isPy3k buildPythonPackage buildPythonApplication;
+  inherit (python.passthru) isPy27 isPy33 isPy34 isPy35 isPy36 isPy37 isPy3k isPyPy pythonAtLeast pythonOlder;
+  inherit python bootstrapped-pip buildPythonPackage buildPythonApplication;
   inherit fetchPypi callPackage;
   inherit hasPythonModule requiredPythonModules makePythonPath disabledIf;
   inherit toPythonModule toPythonApplication;