diff --git a/sim/Cargo.lock b/sim/Cargo.lock
index c16311d..7b4e3a1 100644
--- a/sim/Cargo.lock
+++ b/sim/Cargo.lock
@@ -2,9 +2,8 @@
 name = "bootsim"
 version = "0.1.0"
 dependencies = [
+ "bitflags 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "docopt 0.6.86 (registry+https://github.com/rust-lang/crates.io-index)",
- "enumflags 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "enumflags_derive 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "gcc 0.3.51 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.26 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -47,6 +46,11 @@
 ]
 
 [[package]]
+name = "bitflags"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "cfg-if"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -86,20 +90,6 @@
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "enumflags"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
-name = "enumflags_derive"
-version = "0.2.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.11.11 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
 name = "env_logger"
 version = "0.3.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -167,11 +157,6 @@
 ]
 
 [[package]]
-name = "quote"
-version = "0.3.15"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "rand"
 version = "0.3.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -257,24 +242,6 @@
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "syn"
-version = "0.11.11"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)",
- "synom 0.11.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "unicode-xid 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "synom"
-version = "0.11.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "unicode-xid 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
 name = "thread-id"
 version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -292,11 +259,6 @@
 ]
 
 [[package]]
-name = "unicode-xid"
-version = "0.0.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "untrusted"
 version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -320,13 +282,12 @@
 "checksum aho-corasick 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "ca972c2ea5f742bfce5687b9aef75506a764f61d37f8f649047846a9686ddb66"
 "checksum backtrace 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "72f9b4182546f4b04ebc4ab7f84948953a118bd6021a1b6a6c909e3e94f6be76"
 "checksum backtrace-sys 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "3a0d842ea781ce92be2bf78a9b38883948542749640b8378b3b2f03d1fd9f1ff"
+"checksum bitflags 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4efd02e230a02e18f92fc2735f44597385ed02ad8f831e7c1c1156ee5e1ab3a5"
 "checksum cfg-if 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "d4c819a1287eb618df47cc647173c5c4c66ba19d888a6e50d605672aed3140de"
 "checksum coco 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c06169f5beb7e31c7c67ebf5540b8b472d23e3eade3b2ec7d1f5b504a85f91bd"
 "checksum dbghelp-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "97590ba53bcb8ac28279161ca943a924d1fd4a8fb3fa63302591647c4fc5b850"
 "checksum docopt 0.6.86 (registry+https://github.com/rust-lang/crates.io-index)" = "4a7ef30445607f6fc8720f0a0a2c7442284b629cf0d049286860fae23e71c4d9"
 "checksum either 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "18785c1ba806c258137c937e44ada9ee7e69a37e3c72077542cd2f069d78562a"
-"checksum enumflags 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "b003f771fcd8df873645aa0142c86b50a9d5ce063ca0ce6057a4131f2b6ef3c2"
-"checksum enumflags_derive 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "46ac5d2e0ce7696d1b0c9fb0a1d1c388bc1b04a23b99d54520c15d43ec832466"
 "checksum env_logger 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "15abd780e45b3ea4f76b4e9a26ff4843258dd8a3eed2775a0e7368c2e7936c2f"
 "checksum error-chain 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)" = "318cb3c71ee4cdea69fdc9e15c173b245ed6063e1709029e8fd32525a881120f"
 "checksum futures 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)" = "4b63a4792d4f8f686defe3b39b92127fea6344de5d38202b2ee5a11bbbf29d6a"
@@ -337,7 +298,6 @@
 "checksum log 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)" = "880f77541efa6e5cc74e76910c9884d9859683118839d6a1dc3b11e63512565b"
 "checksum memchr 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "d8b629fb514376c675b98c1421e80b151d3817ac42d7c667717d282761418d20"
 "checksum num_cpus 1.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "aec53c34f2d0247c5ca5d32cca1478762f301740468ee9ee6dcb7a0dd7a0c584"
-"checksum quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e920b65c65f10b2ae65c831a81a073a89edd28c7cce89475bff467ab4167a"
 "checksum rand 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "022e0636ec2519ddae48154b028864bdce4eaf7d35226ab8e65c611be97b189d"
 "checksum rayon 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a77c51c07654ddd93f6cb543c7a849863b03abc7e82591afda6dc8ad4ac3ac4a"
 "checksum rayon-core 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7febc28567082c345f10cddc3612c6ea020fc3297a1977d472cf9fdb73e6e493"
@@ -348,11 +308,8 @@
 "checksum rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)" = "dcf128d1287d2ea9d80910b5f1120d0b8eede3fbf1abe91c40d39ea7d51e6fda"
 "checksum scopeguard 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "c79eb2c3ac4bc2507cda80e7f3ac5b88bd8eae4c0914d5663e6a8933994be918"
 "checksum strsim 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "67f84c44fbb2f91db7fef94554e6b2ac05909c9c0b0bc23bb98d3a1aebfe7f7c"
-"checksum syn 0.11.11 (registry+https://github.com/rust-lang/crates.io-index)" = "d3b891b9015c88c576343b9b3e41c2c11a51c219ef067b264bd9c8aa9b441dad"
-"checksum synom 0.11.3 (registry+https://github.com/rust-lang/crates.io-index)" = "a393066ed9010ebaed60b9eafa373d4b1baac186dd7e008555b0f702b51945b6"
 "checksum thread-id 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a9539db560102d1cef46b8b78ce737ff0bb64e7e18d35b2a5688f7d097d0ff03"
 "checksum thread_local 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)" = "8576dbbfcaef9641452d5cf0df9b0e7eeab7694956dd33bb61515fb8f18cfdd5"
-"checksum unicode-xid 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "8c1f860d7d29cf02cb2f3f359fd35991af3d30bac52c57d265a3c461074cb4dc"
 "checksum untrusted 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "6b65243989ef6aacd9c0d6bd2b822765c3361d8ed352185a6f3a41f3a718c673"
 "checksum utf8-ranges 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "a1ca13c08c41c9c3e04224ed9ff80461d97e121589ff27c753a16cb10830ae0f"
 "checksum winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
diff --git a/sim/Cargo.toml b/sim/Cargo.toml
index 1d294c0..c5b6d81 100644
--- a/sim/Cargo.toml
+++ b/sim/Cargo.toml
@@ -15,8 +15,7 @@
 log = "0.3"
 env_logger = "0.3"
 simflash = { path = "simflash" }
-enumflags = "0.1"
-enumflags_derive = "0.2"
+bitflags = "0.9"
 ring = "0.11"
 
 [profile.test]
diff --git a/sim/src/main.rs b/sim/src/main.rs
index 614def3..89be7ff 100644
--- a/sim/src/main.rs
+++ b/sim/src/main.rs
@@ -1,8 +1,7 @@
 #[macro_use] extern crate log;
 extern crate ring;
 extern crate env_logger;
-extern crate enumflags;
-#[macro_use] extern crate enumflags_derive;
+#[macro_use] extern crate bitflags;
 extern crate docopt;
 extern crate libc;
 extern crate rand;
diff --git a/sim/src/tlv.rs b/sim/src/tlv.rs
index f637443..ac6ac5d 100644
--- a/sim/src/tlv.rs
+++ b/sim/src/tlv.rs
@@ -10,17 +10,16 @@
 
 use ring::digest;
 
-#[derive(EnumFlags, Copy, Clone, Debug)]
-#[repr(u32)]
-#[allow(non_camel_case_types)]
-pub enum Flags {
-    PIC = 0x000001,
-    SHA256 = 0x000002,
-    PKCS15_RSA2048_SHA256 = 0x000004,
-    ECDSA224_SHA256 = 0x000008,
-    NON_BOOTABLE = 0x000010,
-    ECDSA256_SHA256 = 0x000020,
-    PKCS1_PSS_RSA2048_SHA256 = 0x000040,
+bitflags! {
+    struct Flags: u32 {
+        const FLAG_PIC = 0x000001;
+        const FLAG_SHA256 = 0x000002;
+        const FLAG_PKCS15_RSA2048_SHA256 = 0x000004;
+        const FLAG_ECDSA224_SHA256 = 0x000008;
+        const FLAG_NON_BOOTABLE = 0x000010;
+        const FLAG_ECDSA256_SHA256 = 0x000020;
+        const FLAG_PKCS1_PSS_RSA2048_SHA256 = 0x000040;
+    }
 }
 
 #[repr(u8)]
@@ -44,7 +43,7 @@
     /// Construct a new tlv generator that will only contain a hash of the data.
     pub fn new_hash_only() -> TlvGen {
         TlvGen {
-            flags: Flags::SHA256,
+            flags: FLAG_SHA256,
             kinds: vec![TlvKinds::SHA256],
             size: 4 + 32,
             payload: vec![],
@@ -53,7 +52,7 @@
 
     /// Retrieve the header flags for this configuration.  This can be called at any time.
     pub fn get_flags(&self) -> u32 {
-        self.flags as u32
+        self.flags.bits()
     }
 
     /// Retrieve the size that the TLV will occupy.  This can be called at any time.