diff --git a/acme_common/Cargo.toml b/acme_common/Cargo.toml
index 4d9fcbb..9035b1f 100644
--- a/acme_common/Cargo.toml
+++ b/acme_common/Cargo.toml
@@ -21,6 +21,7 @@ handlebars = "3.0"
 log = "0.4"
 native-tls = "0.2"
 openssl = "0.10"
+openssl-sys = "0.9"
 punycode = "0.4"
 serde_json = "1.0"
 syslog = "5.0"
diff --git a/acme_common/build.rs b/acme_common/build.rs
new file mode 100644
index 0000000..b9b5f8d
--- /dev/null
+++ b/acme_common/build.rs
@@ -0,0 +1,72 @@
+use std::env;
+use std::fs::File;
+use std::io::prelude::*;
+use std::io::BufReader;
+use std::path::PathBuf;
+
+macro_rules! set_rustc_env_var {
+    ($name: expr, $value: expr) => {{
+        println!("cargo:rustc-env={}={}", $name, $value);
+    }};
+}
+
+fn get_openssl_version_unit(n: u64, pos: u32) -> u64 {
+    let p = 0x000f_f000_0000 >> (8 * pos);
+    let n = n & p;
+    n >> (8 * (3 - pos) + 4)
+}
+
+fn get_openssl_version(v: &str) -> String {
+    let v = u64::from_str_radix(&v, 16).unwrap();
+    let mut version = vec![];
+    for i in 0..3 {
+        let n = get_openssl_version_unit(v, i);
+        version.push(format!("{}", n));
+    }
+    let version = version.join(".");
+    let p = get_openssl_version_unit(v, 3);
+    if p != 0 {
+        let p = p + 0x60;
+        let p = std::char::from_u32(p as u32).unwrap();
+        format!("{}{}", version, p)
+    } else {
+        version
+    }
+}
+
+fn get_lib_version(lib: &str) -> Option<String> {
+    let pat = format!("\"checksum {} ", lib);
+    let mut lock_file = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
+    lock_file.push("../Cargo.lock");
+    let file = File::open(lock_file).unwrap();
+    for line in BufReader::new(file).lines() {
+        let line = line.unwrap();
+        if line.starts_with(&pat) {
+            let v: Vec<&str> = line.split(' ').collect();
+            return Some(String::from(v[2]));
+        }
+    }
+    None
+}
+
+fn set_tls() {
+    if let Ok(v) = env::var("DEP_OPENSSL_VERSION_NUMBER") {
+        let version = get_openssl_version(&v);
+        set_rustc_env_var!("ACMED_TLS_LIB_VERSION", version);
+        set_rustc_env_var!("ACMED_TLS_LIB_NAME", "OpenSSL");
+    }
+    if let Ok(v) = env::var("DEP_OPENSSL_LIBRESSL_VERSION_NUMBER") {
+        let version = get_openssl_version(&v);
+        set_rustc_env_var!("ACMED_TLS_LIB_VERSION", version);
+        set_rustc_env_var!("ACMED_TLS_LIB_NAME", "LibreSSL");
+    }
+    if env::var("CARGO_FEATURE_STANDALONE").is_ok() {
+        let version = get_lib_version("ring").unwrap();
+        set_rustc_env_var!("ACMED_TLS_LIB_VERSION", version);
+        set_rustc_env_var!("ACMED_TLS_LIB_NAME", "ring");
+    }
+}
+
+fn main() {
+    set_tls();
+}
diff --git a/acme_common/src/crypto.rs b/acme_common/src/crypto.rs
index 6abc4f0..e9897a0 100644
--- a/acme_common/src/crypto.rs
+++ b/acme_common/src/crypto.rs
@@ -4,6 +4,8 @@ mod openssl_hash;
 mod openssl_keys;
 
 pub const DEFAULT_ALGO: &str = "rsa2048";
+pub const TLS_LIB_NAME: &str = env!("ACMED_TLS_LIB_NAME");
+pub const TLS_LIB_VERSION: &str = env!("ACMED_TLS_LIB_VERSION");
 
 pub use key_type::KeyType;
 pub use openssl_certificate::{Csr, X509Certificate};
diff --git a/acmed/Cargo.toml b/acmed/Cargo.toml
index 04446a2..d1017bc 100644
--- a/acmed/Cargo.toml
+++ b/acmed/Cargo.toml
@@ -19,14 +19,13 @@ clap = "2.32"
 handlebars = "3.0"
 log = "0.4"
 nom = "5.0"
-openssl-sys = "0.9"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 toml = "0.5"
 
+[target.'cfg(unix)'.dependencies]
+nix = "0.17"
+
 [build-dependencies]
 serde = { version = "1.0", features = ["derive"] }
 toml = "0.5"
-
-[target.'cfg(unix)'.dependencies]
-nix = "0.17"
diff --git a/acmed/build.rs b/acmed/build.rs
index 9a2715a..fa66262 100644
--- a/acmed/build.rs
+++ b/acmed/build.rs
@@ -5,7 +5,6 @@ use serde::Deserialize;
 use std::env;
 use std::fs::File;
 use std::io::prelude::*;
-use std::io::BufReader;
 use std::path::PathBuf;
 
 macro_rules! set_rustc_env_var {
@@ -68,63 +67,6 @@ fn set_lock() {
     }
 }
 
-fn get_openssl_version_unit(n: u64, pos: u32) -> u64 {
-    let p = 0x000f_f000_0000 >> (8 * pos);
-    let n = n & p;
-    n >> (8 * (3 - pos) + 4)
-}
-
-fn get_openssl_version(v: &str) -> String {
-    let v = u64::from_str_radix(&v, 16).unwrap();
-    let mut version = vec![];
-    for i in 0..3 {
-        let n = get_openssl_version_unit(v, i);
-        version.push(format!("{}", n));
-    }
-    let version = version.join(".");
-    let p = get_openssl_version_unit(v, 3);
-    if p != 0 {
-        let p = p + 0x60;
-        let p = std::char::from_u32(p as u32).unwrap();
-        format!("{}{}", version, p)
-    } else {
-        version
-    }
-}
-
-fn get_lib_version(lib: &str) -> Option<String> {
-    let pat = format!("\"checksum {} ", lib);
-    let mut lock_file = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
-    lock_file.push("../Cargo.lock");
-    let file = File::open(lock_file).unwrap();
-    for line in BufReader::new(file).lines() {
-        let line = line.unwrap();
-        if line.starts_with(&pat) {
-            let v: Vec<&str> = line.split(' ').collect();
-            return Some(String::from(v[2]));
-        }
-    }
-    None
-}
-
-fn set_tls() {
-    if let Ok(v) = env::var("DEP_OPENSSL_VERSION_NUMBER") {
-        let version = get_openssl_version(&v);
-        set_rustc_env_var!("ACMED_TLS_LIB_VERSION", version);
-        set_rustc_env_var!("ACMED_TLS_LIB_NAME", "OpenSSL");
-    }
-    if let Ok(v) = env::var("DEP_OPENSSL_LIBRESSL_VERSION_NUMBER") {
-        let version = get_openssl_version(&v);
-        set_rustc_env_var!("ACMED_TLS_LIB_VERSION", version);
-        set_rustc_env_var!("ACMED_TLS_LIB_NAME", "LibreSSL");
-    }
-    if env::var("CARGO_FEATURE_STANDALONE").is_ok() {
-        let version = get_lib_version("ring").unwrap();
-        set_rustc_env_var!("ACMED_TLS_LIB_VERSION", version);
-        set_rustc_env_var!("ACMED_TLS_LIB_NAME", "ring");
-    }
-}
-
 fn set_target() {
     if let Ok(target) = env::var("TARGET") {
         set_rustc_env_var!("ACMED_TARGET", target);
@@ -133,6 +75,5 @@ fn set_target() {
 
 fn main() {
     set_target();
-    set_tls();
     set_lock();
 }
diff --git a/acmed/src/main.rs b/acmed/src/main.rs
index fe930c7..8ac8ab5 100644
--- a/acmed/src/main.rs
+++ b/acmed/src/main.rs
@@ -1,5 +1,5 @@
 use crate::main_event_loop::MainEventLoop;
-use acme_common::{clean_pid_file, init_server};
+use acme_common::{clean_pid_file, crypto, init_server};
 use clap::{App, Arg};
 use log::error;
 
@@ -40,8 +40,8 @@ fn main() {
         "{} {}\n\nCompiled with:\n  {} {}\n  {} {}",
         APP_VERSION,
         env!("ACMED_TARGET"),
-        env!("ACMED_TLS_LIB_NAME"),
-        env!("ACMED_TLS_LIB_VERSION"),
+        crypto::TLS_LIB_NAME,
+        crypto::TLS_LIB_VERSION,
         env!("ACMED_HTTP_LIB_NAME"),
         env!("ACMED_HTTP_LIB_VERSION")
     );