diff --git a/Cargo.lock b/Cargo.lock
index 9ca72b2b..29534203 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -51,7 +51,7 @@ dependencies = [
 
 [[package]]
 name = "base64"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "byteorder 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -63,7 +63,7 @@ name = "bcrypt"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "base64 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "base64 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "blowfish 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "byte-tools 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -229,6 +229,19 @@ dependencies = [
  "backtrace 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "foreign-types"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "foreign-types-shared 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "foreign-types-shared"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "fuchsia-zircon"
 version = "0.3.3"
@@ -269,6 +282,11 @@ dependencies = [
  "unicode-segmentation 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "hex"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "httparse"
 version = "1.2.4"
@@ -433,6 +451,29 @@ name = "opaque-debug"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "openssl"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitflags 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "foreign-types 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.40 (registry+https://github.com/rust-lang/crates.io-index)",
+ "openssl-sys 0.9.28 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "openssl-sys"
+version = "0.9.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cc 1.0.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.40 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pkg-config 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "vcpkg 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "ordermap"
 version = "0.2.13"
@@ -462,14 +503,23 @@ name = "pest"
 version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "pkg-config"
+version = "0.3.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "plume"
 version = "0.1.0"
 dependencies = [
+ "base64 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "bcrypt 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "chrono 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "diesel 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "dotenv 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "heck 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "openssl 0.10.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "rocket 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "rocket_codegen 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "rocket_contrib 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -932,7 +982,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum backtrace 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "ebbe525f66f42d207968308ee86bc2dd60aa5fab535b22e616323a173d097d8e"
 "checksum backtrace-sys 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)" = "44585761d6161b0f57afc49482ab6bd067e4edef48c12a152c237eb0203f7661"
 "checksum base64 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "96434f987501f0ed4eb336a411e0631ecd1afa11574fe148587adc4ff96143c9"
-"checksum base64 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "229d032f1a99302697f10b27167ae6d03d49d032e6a8e2550e8d3fc13356d2b4"
+"checksum base64 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9263aa6a38da271eec5c91a83ce1e800f093c8535788d403d626d8d5c3f8f007"
 "checksum bcrypt 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1a1512813db09170b44a00870b58421876d797b77b085c5205a24db90905f758"
 "checksum bitflags 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b3c30d3802dfb7281680d6285f2ccdaa8c2d8fee41f93805dba5c4cf50dc23cf"
 "checksum block-cipher-trait 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d6136d803280ae3532efa36114335255ea94f3d75d735ddedd66b0d7cd30bad3"
@@ -953,12 +1003,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum dtoa 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "09c3753c3db574d215cba4ea76018483895d7bff25a31b49ba45db21c48e50ab"
 "checksum error-chain 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d9435d864e017c3c6afeac1654189b06cdb491cf2ff73dbf0d73b0f292f42ff8"
 "checksum error-chain 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ff511d5dc435d703f4971bc399647c9bc38e20cb41452e3b9feb4765419ed3f3"
+"checksum foreign-types 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f6f339eb8adc052cd2ca78910fda869aefa38d22d5cb648e6485e4d3fc06f3b1"
+"checksum foreign-types-shared 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "00b0228411908ca8685dba7fc2cdd70ec9990a6e753e89b6ac91a84c40fbaf4b"
 "checksum fuchsia-zircon 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2e9763c69ebaae630ba35f74888db465e49e259ba1bc0eda7d06f4a067615d82"
 "checksum fuchsia-zircon-sys 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3dcaa9ae7725d12cdb85b3ad99a434db70b468c09ded17e012d86b5c1010f7a7"
 "checksum gcc 0.3.54 (registry+https://github.com/rust-lang/crates.io-index)" = "5e33ec290da0d127825013597dbdfc28bee4964690c7ce1166cbc2a7bd08b1bb"
 "checksum generic-array 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ef25c5683767570c2bbd7deba372926a55eaae9982d7726ee2a1050239d45b9d"
 "checksum glob 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "8be18de09a56b60ed0edf84bc9df007e30040691af7acd1c41874faac5895bfb"
 "checksum heck 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ea04fa3ead4e05e51a7c806fc07271fdbde4e246a6c6d1efd52e72230b771b82"
+"checksum hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "805026a5d0141ffc30abb3be3173848ad46a1b1664fe632428479619a3644d77"
 "checksum httparse 1.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "c2f407128745b78abc95c0ffbe4e5d37427fdc0d45470710cfef8c44522a2e37"
 "checksum humansize 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b6cab2627acfc432780848602f3f558f7e9dd427352224b0d9324025796d2a5e"
 "checksum hyper 0.10.13 (registry+https://github.com/rust-lang/crates.io-index)" = "368cb56b2740ebf4230520e2b90ebb0461e69034d85d1945febd9b3971426db2"
@@ -982,11 +1035,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum num-traits 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "dee092fcdf725aee04dd7da1d21debff559237d49ef1cb3e69bcb8ece44c7364"
 "checksum num_cpus 1.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c51a3322e4bca9d212ad9a158a02abc6934d005490c054a2778df73a70aa0a30"
 "checksum opaque-debug 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d620c9c26834b34f039489ac0dfdb12c7ac15ccaf818350a64c9b5334a452ad7"
+"checksum openssl 0.10.6 (registry+https://github.com/rust-lang/crates.io-index)" = "63246f69962e8d5ef865f82a65241d6483c8a2905a1801e2f7feb5d187d51320"
+"checksum openssl-sys 0.9.28 (registry+https://github.com/rust-lang/crates.io-index)" = "0bbd90640b148b46305c1691eed6039b5c8509bed16991e3562a01eeb76902a3"
 "checksum ordermap 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)" = "b81cf3b8cb96aa0e73bbedfcdc9708d09fec2854ba8d474be4e6f666d7379e8b"
 "checksum pear 0.0.16 (registry+https://github.com/rust-lang/crates.io-index)" = "b9b645aa07cf1010a67e9f67b4b9b96d6c5fb9315eee678a061d6ab58e9cb77f"
 "checksum pear_codegen 0.0.16 (registry+https://github.com/rust-lang/crates.io-index)" = "ca34109829349aeefe22772916da5404b3f5cd0e63a72c5d91209fc809342265"
 "checksum percent-encoding 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "31010dd2e1ac33d5b46a5b413495239882813e0369f8ed8a5e266f173602f831"
 "checksum pest 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3e2e823a5967bb4cdc6d3e46f47baaf4ecfeae44413a642b74ad44e59e49c7f6"
+"checksum pkg-config 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)" = "110d5ee3593dbb73f56294327fe5668bcc997897097cbc76b51e7aed3f52452f"
 "checksum pq-sys 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)" = "4dfb5e575ef93a1b7b2a381d47ba7c5d4e4f73bff37cee932195de769aad9a54"
 "checksum proc-macro2 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "cd07deb3c6d1d9ff827999c7f9b04cdfd66b1b17ae508e14fe47b620f2282ae0"
 "checksum proc-macro2 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "49b6a521dc81b643e9a51e0d1cf05df46d5a2f3c0280ea72bcb68276ba64a118"
diff --git a/Cargo.toml b/Cargo.toml
index 34b3bb3f..b90d62a8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,9 +3,13 @@ authors = ["Bat' <baptiste@gelez.xyz>"]
 name = "plume"
 version = "0.1.0"
 [dependencies]
+base64 = "0.9.1"
 bcrypt = "0.2"
+chrono = "0.4"
 dotenv = "*"
 heck = "0.3.0"
+hex = "0.3"
+openssl = "0.10.6"
 rocket = "*"
 rocket_codegen = "*"
 serde = "*"
diff --git a/src/activity_pub/activity.rs b/src/activity_pub/activity.rs
index 790d6956..b3e6a60f 100644
--- a/src/activity_pub/activity.rs
+++ b/src/activity_pub/activity.rs
@@ -14,3 +14,4 @@ impl<'a, T: Actor, U: Object> Create<'a, T, U> {
         }
     }
 }
+
diff --git a/src/activity_pub/sign.rs b/src/activity_pub/sign.rs
new file mode 100644
index 00000000..000c9930
--- /dev/null
+++ b/src/activity_pub/sign.rs
@@ -0,0 +1,44 @@
+use base64;
+use hex;
+use chrono::Utc;
+use openssl::sha::{sha256, sha512};
+use serde_json;
+
+// Comments are from the Mastodon source code, to knremow what to do.
+
+pub trait Signer {
+    fn get_key_id(&self) -> String;
+    
+    /// Sign some data with the signer keypair
+    fn sign(&self, to_sign: String) -> String; // Base64.strict_encode64(creator.keypair.sign(OpenSSL::Digest::SHA256.new, to_be_signed))
+}
+
+pub trait Signable {
+    fn sign<T>(&mut self, creator: T) -> &mut Self where T: Signer;
+
+    fn hash(data: String) -> String {
+        let bytes = data.into_bytes();
+        hex::encode(sha256(&bytes[..]))
+    }
+}
+
+impl Signable for serde_json::Value {
+    fn sign<T>(&mut self, creator: T) -> &mut serde_json::Value where T: Signer {
+        let mut options = json!({
+            "type": "RsaSignature2017",
+            "creator": creator.get_key_id(), // [ActivityPub::TagManager.instance.uri_for(creator), '#main-key'].join,
+            "created": Utc::now().to_rfc3339()
+        });
+
+        //options_hash  = hash(options.without('type', 'id', 'signatureValue').merge('@context' => CONTEXT))
+        let options_hash = Self::hash(String::from(""));
+        let document_hash = Self::hash(self.to_string());
+        let to_be_signed = options_hash + &document_hash;
+
+        let signature = base64::encode(&creator.sign(to_be_signed));
+
+        options["signaureValue"] = serde_json::Value::String(signature);
+        self["signature"] = options;
+        self
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index acdf4fea..e5876119 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,11 +1,15 @@
 #![feature(plugin, custom_derive)]
 #![plugin(rocket_codegen)]
 
+extern crate base64;
 extern crate bcrypt;
+extern crate chrono;
 extern crate heck;
+extern crate hex;
 #[macro_use]
 extern crate diesel;
 extern crate dotenv;
+extern crate openssl;
 extern crate rocket;
 extern crate rocket_contrib;
 #[feature(custom_attribute)]