{ stdenv, version, kernelPlatform, extraConfig, features }:

with stdenv.lib;

''
  # Debugging.
  DEBUG_KERNEL y
  TIMER_STATS y
  BACKTRACE_SELF_TEST n
  CPU_NOTIFIER_ERROR_INJECT? n
  DEBUG_DEVRES n
  DEBUG_NX_TEST n
  DEBUG_STACK_USAGE n
  ${optionalString (!(features.grsecurity or false)) ''
    DEBUG_STACKOVERFLOW n
  ''}
  RCU_TORTURE_TEST n
  SCHEDSTATS n
  DETECT_HUNG_TASK y

  # Power management.
  ${optionalString (versionOlder version "3.19") ''
    PM_RUNTIME y
  ''}
  PM_ADVANCED_DEBUG y
  ${optionalString (versionAtLeast version "3.10") ''
    X86_INTEL_PSTATE y
  ''}
  INTEL_IDLE y
  CPU_FREQ_DEFAULT_GOV_PERFORMANCE y
  ${optionalString (versionOlder version "3.10") ''
    USB_SUSPEND y
  ''}

  # Support drivers that need external firmware.
  STANDALONE n

  # Make /proc/config.gz available.
  IKCONFIG_PROC y

  # Optimize with -O2, not -Os.
  CC_OPTIMIZE_FOR_SIZE n

  # Enable the kernel's built-in memory tester.
  MEMTEST y

  # Include the CFQ I/O scheduler in the kernel, rather than as a
  # module, so that the initrd gets a good I/O scheduler.
  IOSCHED_CFQ y
  BLK_CGROUP y # required by CFQ

  # Enable NUMA.
  NUMA? y

  # Disable some expensive (?) features.
  KPROBES n
  PM_TRACE_RTC n

  # Enable various subsystems.
  ACCESSIBILITY y # Accessibility support
  AUXDISPLAY y # Auxiliary Display support
  DONGLE y # Serial dongle support
  HIPPI y
  MTD_COMPLEX_MAPPINGS y # needed for many devices
  ${optionalString (versionOlder version "3.2") ''
    NET_POCKET y # enable pocket and portable adapters
  ''}
  SCSI_LOWLEVEL y # enable lots of SCSI devices
  SCSI_LOWLEVEL_PCMCIA y
  SCSI_SAS_ATA y  # added to enable detection of hard drive
  SPI y # needed for many devices
  SPI_MASTER y
  WAN y

  # Networking options.
  IP_PNP n
  ${optionalString (versionOlder version "3.13") ''
    IPV6_PRIVACY y
  ''}
  NETFILTER_ADVANCED y
  IP_VS_PROTO_TCP y
  IP_VS_PROTO_UDP y
  IP_VS_PROTO_ESP y
  IP_VS_PROTO_AH y
  IP_DCCP_CCID3 n # experimental
  CLS_U32_PERF y
  CLS_U32_MARK y
  ${optionalString (stdenv.system == "x86_64-linux") ''
    BPF_JIT y
  ''}

  # Wireless networking.
  CFG80211_WEXT? y # Without it, ipw2200 drivers don't build
  IPW2100_MONITOR? y # support promiscuous mode
  IPW2200_MONITOR? y # support promiscuous mode
  HOSTAP_FIRMWARE? y # Support downloading firmware images with Host AP driver
  HOSTAP_FIRMWARE_NVRAM? y
  ATH9K_PCI? y # Detect Atheros AR9xxx cards on PCI(e) bus
  ATH9K_AHB? y # Ditto, AHB bus
  ${optionalString (versionAtLeast version "3.2") ''
    B43_PHY_HT? y
  ''}
  BCMA_HOST_PCI? y

  # Enable various FB devices.
  FB y
  FB_EFI y
  FB_NVIDIA_I2C y # Enable DDC Support
  FB_RIVA_I2C y
  FB_ATY_CT y # Mach64 CT/VT/GT/LT (incl. 3D RAGE) support
  FB_ATY_GX y # Mach64 GX support
  FB_SAVAGE_I2C y
  FB_SAVAGE_ACCEL y
  FB_SIS_300 y
  FB_SIS_315 y
  FB_3DFX_ACCEL y
  ${optionalString (versionOlder version "3.9" || stdenv.system == "i686-linux") ''
    FB_GEODE y
  ''}

  # Video configuration.
  # Enable KMS for devices whose X.org driver supports it.
  DRM_I915_KMS y
  ${optionalString (versionOlder version "3.9") ''
    DRM_RADEON_KMS? y
  ''}
  # Hybrid graphics support
  VGA_SWITCHEROO y

  # Sound.
  SND_DYNAMIC_MINORS y
  SND_AC97_POWER_SAVE y # AC97 Power-Saving Mode
  SND_HDA_INPUT_BEEP y # Support digital beep via input layer
  SND_USB_CAIAQ_INPUT y
  PSS_MIXER y # Enable PSS mixer (Beethoven ADSP-16 and other compatible)

  # USB serial devices.
  USB_SERIAL_GENERIC y # USB Generic Serial Driver
  USB_SERIAL_KEYSPAN_MPR y # include firmware for various USB serial devices
  USB_SERIAL_KEYSPAN_USA28 y
  USB_SERIAL_KEYSPAN_USA28X y
  USB_SERIAL_KEYSPAN_USA28XA y
  USB_SERIAL_KEYSPAN_USA28XB y
  USB_SERIAL_KEYSPAN_USA19 y
  USB_SERIAL_KEYSPAN_USA18X y
  USB_SERIAL_KEYSPAN_USA19W y
  USB_SERIAL_KEYSPAN_USA19QW y
  USB_SERIAL_KEYSPAN_USA19QI y
  USB_SERIAL_KEYSPAN_USA49W y
  USB_SERIAL_KEYSPAN_USA49WLC y

  # Filesystem options - in particular, enable extended attributes and
  # ACLs for all filesystems that support them.
  FANOTIFY y
  EXT2_FS_XATTR y
  EXT2_FS_POSIX_ACL y
  EXT2_FS_SECURITY y
  ${optionalString (versionOlder version "4.0") ''
    EXT2_FS_XIP y # Ext2 execute in place support
  ''}
  EXT3_FS_POSIX_ACL y
  EXT3_FS_SECURITY y
  EXT4_FS_POSIX_ACL y
  EXT4_FS_SECURITY y
  REISERFS_FS_XATTR? y
  REISERFS_FS_POSIX_ACL? y
  REISERFS_FS_SECURITY? y
  JFS_POSIX_ACL? y
  JFS_SECURITY? y
  XFS_QUOTA? y
  XFS_POSIX_ACL? y
  XFS_RT? y # XFS Realtime subvolume support
  OCFS2_DEBUG_MASKLOG? n
  BTRFS_FS_POSIX_ACL y
  UBIFS_FS_XATTR? y
  UBIFS_FS_ADVANCED_COMPR? y
  ${optionalString (versionAtLeast version "3.6") ''
    NFS_SWAP y
  ''}
  ${optionalString (versionAtLeast version "3.11") ''
    NFS_V4_1 y  # NFSv4.1 client support
    NFS_V4_2 y
  ''}
  NFSD_V2_ACL y
  NFSD_V3 y
  NFSD_V3_ACL y
  NFSD_V4 y
  NFS_FSCACHE y
  CIFS_XATTR y
  CIFS_POSIX y
  CIFS_FSCACHE y
  ${optionalString (versionAtLeast version "3.12") ''
    CEPH_FSCACHE y
  ''}
  ${optionalString (versionAtLeast version "3.14") ''
    CEPH_FS_POSIX_ACL y
  ''}

  # Security related features.
  STRICT_DEVMEM y # Filter access to /dev/mem
  SECURITY_SELINUX_BOOTPARAM_VALUE 0 # Disable SELinux by default
  DEVKMEM? n # Disable /dev/kmem
  ${if versionOlder version "3.14" then ''
    CC_STACKPROTECTOR? y # Detect buffer overflows on the stack
  '' else ''
    CC_STACKPROTECTOR_REGULAR? y
  ''}
  ${optionalString (versionAtLeast version "3.12") ''
    USER_NS y # Support for user namespaces
  ''}

  # AppArmor support
  SECURITY_APPARMOR y
  DEFAULT_SECURITY_APPARMOR y

  # Misc. options.
  8139TOO_8129 y
  8139TOO_PIO n # PIO is slower
  AIC79XX_DEBUG_ENABLE n
  AIC7XXX_DEBUG_ENABLE n
  AIC94XX_DEBUG n
  ${optionalString (versionAtLeast version "3.3" && versionOlder version "3.13") ''
    AUDIT_LOGINUID_IMMUTABLE y
  ''}
  B43_PCMCIA? y
  BLK_DEV_CMD640_ENHANCED y # CMD640 enhanced support
  BLK_DEV_IDEACPI y # IDE ACPI support
  BLK_DEV_INTEGRITY y
  BSD_PROCESS_ACCT_V3 y
  BT_HCIUART_BCSP? y
  BT_HCIUART_H4? y # UART (H4) protocol support
  BT_HCIUART_LL? y
  BT_RFCOMM_TTY? y # RFCOMM TTY support
  CRASH_DUMP? n
  ${optionalString (versionOlder version "3.1") ''
    DMAR? n # experimental
  ''}
  DVB_DYNAMIC_MINORS? y # we use udev
  ${optionalString (versionAtLeast version "3.3") ''
    EFI_STUB y # EFI bootloader in the bzImage itself
  ''}
  FHANDLE y # used by systemd
  FUSION y # Fusion MPT device support
  IDE_GD_ATAPI y # ATAPI floppy support
  IRDA_ULTRA y # Ultra (connectionless) protocol
  JOYSTICK_IFORCE_232? y # I-Force Serial joysticks and wheels
  JOYSTICK_IFORCE_USB? y # I-Force USB joysticks and wheels
  JOYSTICK_XPAD_FF? y # X-Box gamepad rumble support
  JOYSTICK_XPAD_LEDS? y # LED Support for Xbox360 controller 'BigX' LED
  LDM_PARTITION y # Windows Logical Disk Manager (Dynamic Disk) support
  LEDS_TRIGGER_IDE_DISK y # LED IDE Disk Trigger
  LOGIRUMBLEPAD2_FF y # Logitech Rumblepad 2 force feedback
  LOGO n # not needed
  MEDIA_ATTACH y
  MEGARAID_NEWGEN y
  MICROCODE_AMD y
  MODVERSIONS y
  MOUSE_PS2_ELANTECH y # Elantech PS/2 protocol extension
  MTRR_SANITIZER y
  NET_FC y # Fibre Channel driver support
  PPP_MULTILINK y # PPP multilink support
  PPP_FILTER y
  REGULATOR y # Voltage and Current Regulator Support
  ${optionalString (versionAtLeast version "3.6") ''
    RC_DEVICES? y # Enable IR devices
  ''}
  SCSI_LOGGING y # SCSI logging facility
  SERIAL_8250 y # 8250/16550 and compatible serial support
  SLIP_COMPRESSED y # CSLIP compressed headers
  SLIP_SMART y
  THERMAL_HWMON y # Hardware monitoring support
  ${optionalString (versionAtLeast version "3.15") ''
    UEVENT_HELPER n
  ''}
  USB_DEBUG? n
  USB_EHCI_ROOT_HUB_TT y # Root Hub Transaction Translators
  USB_EHCI_TT_NEWSCHED y # Improved transaction translator scheduling
  X86_CHECK_BIOS_CORRUPTION y
  X86_MCE y

  # Linux containers.
  RT_GROUP_SCHED? y
  CGROUP_DEVICE? y
  ${if versionAtLeast version "3.6" then ''
    MEMCG y
    MEMCG_SWAP y
  '' else ''
    CGROUP_MEM_RES_CTLR y
    CGROUP_MEM_RES_CTLR_SWAP y
  ''}
  DEVPTS_MULTIPLE_INSTANCES y
  BLK_DEV_THROTTLING y
  CFQ_GROUP_IOSCHED y

  # Enable staging drivers.  These are somewhat experimental, but
  # they generally don't hurt.
  STAGING y

  # PROC_EVENTS requires that the netlink connector is not built
  # as a module.  This is required by libcgroup's cgrulesengd.
  CONNECTOR y
  PROC_EVENTS y

  # Tracing.
  FTRACE y
  FUNCTION_TRACER y
  FTRACE_SYSCALLS y
  SCHED_TRACER y

  # Devtmpfs support.
  DEVTMPFS y

  # Easier debugging of NFS issues.
  ${optionalString (versionAtLeast version "3.4") ''
    SUNRPC_DEBUG y
  ''}

  # Virtualisation.
  PARAVIRT? y
  ${if versionAtLeast version "3.10" then ''
    HYPERVISOR_GUEST? y
  '' else ''
    PARAVIRT_GUEST? y
  ''}
  KVM_GUEST? y
  ${optionalString (versionOlder version "3.7") ''
    KVM_CLOCK? y
  ''}
  XEN? y
  XEN_DOM0? y
  ${optionalString ((versionAtLeast version "3.18") && (features.xen_dom0 or false))  ''
    PCI_XEN? y
    HVC_XEN? y
    HVC_XEN_FRONTEND? y
    XEN_SYS_HYPERVISOR? y
    SWIOTLB_XEN? y
    XEN_BACKEND? y
    XEN_BALLOON? y
    XEN_BALLOON_MEMORY_HOTPLUG? y
    XEN_EFI? y
    XEN_HAVE_PVMMU? y
    XEN_MCE_LOG? y
    XEN_PVH? y
    XEN_PVHVM? y
    XEN_SAVE_RESTORE? y
    XEN_SCRUB_PAGES? y
    XEN_SELFBALLOONING? y
    XEN_STUB? y
    XEN_TMEM? y
  ''}
  KSM y
  ${optionalString (!stdenv.is64bit) ''
    HIGHMEM64G? y # We need 64 GB (PAE) support for Xen guest support.
  ''}
  ${optionalString (versionAtLeast version "3.9" && stdenv.is64bit) ''
    VFIO_PCI_VGA y
  ''}
  VIRT_DRIVERS y

  # Media support.
  ${optionalString (versionAtLeast version "3.6") ''
    MEDIA_DIGITAL_TV_SUPPORT y
    MEDIA_CAMERA_SUPPORT y
    MEDIA_RC_SUPPORT y
  ''}
  ${optionalString (versionAtLeast version "3.7") ''
    MEDIA_USB_SUPPORT y
  ''}

  # Our initrd init uses shebang scripts, so can't be modular.
  ${optionalString (versionAtLeast version "3.10") ''
    BINFMT_SCRIPT y
  ''}

  # Enable the 9P cache to speed up NixOS VM tests.
  9P_FSCACHE? y
  9P_FS_POSIX_ACL? y

  # Enable transparent support for huge pages.
  TRANSPARENT_HUGEPAGE? y
  TRANSPARENT_HUGEPAGE_ALWAYS? n
  TRANSPARENT_HUGEPAGE_MADVISE? y

  # zram support (e.g for in-memory compressed swap).
  ${optionalString (versionAtLeast version "3.4") ''
    ZSMALLOC y
  ''}
  ZRAM m

  ${optionalString (versionAtLeast version "3.17") "NFC? n"}

  # Enable firmware loading via udev. Only needed for non-declarative
  # firmware in /root/test-firmware.
  ${optionalString (versionAtLeast version "3.17") ''
    FW_LOADER_USER_HELPER_FALLBACK y
  ''}

  ${kernelPlatform.kernelExtraConfig or ""}
  ${extraConfig}
''