diff --git a/Cargo.lock b/Cargo.lock
index 981f146..c1d40c4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,17 +1,3 @@
-[root]
-name = "powersoftau"
-version = "0.1.1"
-dependencies = [
- "blake2 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "byteorder 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "crossbeam 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "generic-array 0.8.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "num_cpus 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "pairing 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.3.17 (registry+https://github.com/rust-lang/crates.io-index)",
- "typenum 1.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "bitflags"
 version = "0.7.0"
@@ -81,6 +67,11 @@ dependencies = [
  "bitflags 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "gcc"
+version = "0.3.54"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "generic-array"
 version = "0.8.3"
@@ -90,6 +81,23 @@ dependencies = [
  "typenum 1.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "hex-literal"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "hex-literal-impl 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro-hack 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "hex-literal-impl"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro-hack 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "libc"
 version = "0.2.32"
@@ -117,6 +125,35 @@ dependencies = [
  "rand 0.3.17 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "powersoftau"
+version = "0.1.1"
+dependencies = [
+ "blake2 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "byteorder 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "generic-array 0.8.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hex-literal 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num_cpus 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pairing 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.3.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rust-crypto 0.2.36 (registry+https://github.com/rust-lang/crates.io-index)",
+ "typenum 1.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "proc-macro-hack"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro-hack-impl 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "proc-macro-hack-impl"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "rand"
 version = "0.3.17"
@@ -126,11 +163,62 @@ dependencies = [
  "libc 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "redox_syscall"
+version = "0.1.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "rust-crypto"
+version = "0.2.36"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "gcc 0.3.54 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.3.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)",
+ "time 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rustc-serialize"
+version = "0.3.24"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "time"
+version = "0.1.39"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "libc 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "redox_syscall 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "typenum"
 version = "1.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "winapi"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [metadata]
 "checksum bitflags 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "aad18937a628ec6abcd26d1489012cc0e18c21798210f491af69ded9b881106d"
 "checksum blake2 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)" = "53bf612c0f2839b7e764ebac65d6cb985f7c6812de399d0728038f4b1da141bc"
@@ -142,10 +230,22 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum digest 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e5b29bf156f3f4b3c4f610a25ff69370616ae6e0657d416de22645483e72af0a"
 "checksum fuchsia-zircon 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "f6c0581a4e363262e52b87f59ee2afe3415361c6ec35e665924eb08afe8ff159"
 "checksum fuchsia-zircon-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "43f3795b4bae048dc6123a6b972cadde2e676f9ded08aef6bb77f5f157684a82"
+"checksum gcc 0.3.54 (registry+https://github.com/rust-lang/crates.io-index)" = "5e33ec290da0d127825013597dbdfc28bee4964690c7ce1166cbc2a7bd08b1bb"
 "checksum generic-array 0.8.3 (registry+https://github.com/rust-lang/crates.io-index)" = "fceb69994e330afed50c93524be68c42fa898c2d9fd4ee8da03bd7363acd26f2"
+"checksum hex-literal 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4da5f0e01bd8a71a224a4eedecaacfcabda388dbb7a80faf04d3514287572d95"
+"checksum hex-literal-impl 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "1d340b6514f232f6db1bd16db65302a5278a04fef9ce867cb932e7e5fa21130a"
 "checksum libc 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)" = "56cce3130fd040c28df6f495c8492e5ec5808fb4c9093c310df02b0c8f030148"
 "checksum nodrop 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)" = "9a2228dca57108069a5262f2ed8bd2e82496d2e074a06d1ccc7ce1687b6ae0a2"
 "checksum num_cpus 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "514f0d73e64be53ff320680ca671b64fe3fb91da01e1ae2ddc99eb51d453b20d"
 "checksum pairing 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c6cecc13d1871265fea9be96aa9f1cc027edacd55d2fb1fbc164e19725b88d70"
+"checksum proc-macro-hack 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3ba8d4f9257b85eb6cdf13f055cea3190520aab1409ca2ab43493ea4820c25f0"
+"checksum proc-macro-hack-impl 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d5cb6f960ad471404618e9817c0e5d10b1ae74cfdf01fab89ea0641fe7fb2892"
 "checksum rand 0.3.17 (registry+https://github.com/rust-lang/crates.io-index)" = "61efcbcd9fa8d8fbb07c84e34a8af18a1ff177b449689ad38a6e9457ecc7b2ae"
+"checksum redox_syscall 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)" = "0d92eecebad22b767915e4d529f89f28ee96dbbf5a4810d2b844373f136417fd"
+"checksum rust-crypto 0.2.36 (registry+https://github.com/rust-lang/crates.io-index)" = "f76d05d3993fd5f4af9434e8e436db163a12a9d40e1a58a726f27a01dfd12a2a"
+"checksum rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)" = "dcf128d1287d2ea9d80910b5f1120d0b8eede3fbf1abe91c40d39ea7d51e6fda"
+"checksum time 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)" = "a15375f1df02096fb3317256ce2cee6a1f42fc84ea5ad5fc8c421cfe40c73098"
 "checksum typenum 1.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "13a99dc6780ef33c78780b826cf9d2a78840b72cae9474de4bcaf9051e60ebbd"
+"checksum winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "04e3bd221fcbe8a271359c04f21a76db7d0c6028862d1bb5512d85e1e2eb5bb3"
+"checksum winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+"checksum winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
diff --git a/Cargo.toml b/Cargo.toml
index b491296..9b150fe 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,6 +18,8 @@ generic-array = "0.8.3"
 typenum = "1.9.0"
 byteorder = "1.1.0"
 pairing = "0.13.0"
+hex-literal = "0.1"
+rust-crypto = "0.2"
 
 [features]
 u128-support = ["pairing/u128-support"]
diff --git a/src/bin/beacon.rs b/src/bin/beacon.rs
new file mode 100644
index 0000000..a76d0d2
--- /dev/null
+++ b/src/bin/beacon.rs
@@ -0,0 +1,142 @@
+extern crate powersoftau;
+extern crate rand;
+extern crate blake2;
+extern crate byteorder;
+
+#[macro_use]
+extern crate hex_literal;
+
+extern crate crypto;
+
+use powersoftau::*;
+
+use std::fs::OpenOptions;
+use std::io::{Read, BufReader, Write, BufWriter};
+
+fn main() {
+    // Create an RNG based on the outcome of the random beacon
+    let mut rng = {
+        use byteorder::{ReadBytesExt, BigEndian};
+        use rand::{SeedableRng};
+        use rand::chacha::ChaChaRng;
+        use crypto::sha2::Sha256;
+        use crypto::digest::Digest;
+
+        // Place block hash here (this will change)
+        let mut cur_hash: [u8; 32] = hex!("000000000000000000357b7d5040ee362f037bdf873eb4cde615b2f368f2f2a6");
+
+        // Performs 2^n hash iterations over it
+        const N: usize = 40;
+
+        for i in 0..(1u64<<N) {
+            // Print 1024 of the interstitial states
+            // so that verification can be
+            // parallelized
+            if i % (1u64<<(N-10)) == 0 {
+                print!("{}: ", i);
+                for b in cur_hash.iter() {
+                    print!("{:02x}", b);
+                }
+                println!("");
+            }
+
+            let mut h = Sha256::new();
+            h.input(&cur_hash);
+            h.result(&mut cur_hash);
+        }
+
+        print!("Final result of beacon: ");
+        for b in cur_hash.iter() {
+            print!("{:02x}", b);
+        }
+        println!("");
+
+        let mut digest = &cur_hash[..];
+
+        let mut seed = [0u32; 8];
+        for i in 0..8 {
+            seed[i] = digest.read_u32::<BigEndian>().expect("digest is large enough for this to work");
+        }
+
+        ChaChaRng::from_seed(&seed)
+    };
+
+    // Try to load `./challenge` from disk.
+    let reader = OpenOptions::new()
+                            .read(true)
+                            .open("challenge").expect("unable open `./challenge` in this directory");
+
+    {
+        let metadata = reader.metadata().expect("unable to get filesystem metadata for `./challenge`");
+        if metadata.len() != (ACCUMULATOR_BYTE_SIZE as u64) {
+            panic!("The size of `./challenge` should be {}, but it's {}, so something isn't right.", ACCUMULATOR_BYTE_SIZE, metadata.len());
+        }
+    }
+
+    let reader = BufReader::new(reader);
+    let mut reader = HashReader::new(reader);
+
+    // Create `./response` in this directory
+    let writer = OpenOptions::new()
+                            .read(false)
+                            .write(true)
+                            .create_new(true)
+                            .open("response").expect("unable to create `./response` in this directory");
+
+    let writer = BufWriter::new(writer);
+    let mut writer = HashWriter::new(writer);
+    
+    println!("Reading `./challenge` into memory...");
+
+    // Read the BLAKE2b hash of the previous contribution
+    {
+        // We don't need to do anything with it, but it's important for
+        // the hash chain.
+        let mut tmp = [0; 64];
+        reader.read_exact(&mut tmp).expect("unable to read BLAKE2b hash of previous contribution");
+    }
+
+    // Load the current accumulator into memory
+    let mut current_accumulator = Accumulator::deserialize(&mut reader, UseCompression::No, CheckForCorrectness::No).expect("unable to read uncompressed accumulator");
+    
+    // Get the hash of the current accumulator
+    let current_accumulator_hash = reader.into_hash();
+
+    // Construct our keypair using the RNG we created above
+    let (pubkey, privkey) = keypair(&mut rng, current_accumulator_hash.as_ref());
+
+    // Perform the transformation
+    println!("Computing, this could take a while...");
+    current_accumulator.transform(&privkey);
+    println!("Writing your contribution to `./response`...");
+
+    // Write the hash of the input accumulator
+    writer.write_all(&current_accumulator_hash.as_ref()).expect("unable to write BLAKE2b hash of input accumulator");
+
+    // Write the transformed accumulator (in compressed form, to save upload bandwidth for disadvantaged
+    // players.)
+    current_accumulator.serialize(&mut writer, UseCompression::Yes).expect("unable to write transformed accumulator");
+
+    // Write the public key
+    pubkey.serialize(&mut writer).expect("unable to write public key");
+
+    // Get the hash of the contribution, so the user can compare later
+    let contribution_hash = writer.into_hash();
+
+    print!("Done!\n\n\
+              Your contribution has been written to `./response`\n\n\
+              The BLAKE2b hash of `./response` is:\n");
+
+    for line in contribution_hash.as_slice().chunks(16) {
+        print!("\t");
+        for section in line.chunks(4) {
+            for b in section {
+                print!("{:02x}", b);
+            }
+            print!(" ");
+        }
+        println!("");
+    }
+
+    println!("\n");
+}