diff --git a/acme_common/Cargo.toml b/acme_common/Cargo.toml
index b25f035..2f15298 100644
--- a/acme_common/Cargo.toml
+++ b/acme_common/Cargo.toml
@@ -12,6 +12,9 @@ publish = false
 [lib]
 name = "acme_common"
 
+[features]
+openssl_dyn = ["openssl", "openssl-sys"]
+
 [dependencies]
 attohttpc = { version = "0.15", default-features = false }
 base64 = "0.12"
@@ -20,8 +23,8 @@ env_logger = "0.7"
 handlebars = "3.0"
 log = "0.4"
 native-tls = "0.2"
-openssl = "0.10"
-openssl-sys = "0.9"
+openssl = { version = "0.10", optional = true }
+openssl-sys = { version = "0.9", optional = true }
 punycode = "0.4"
 serde_json = "1.0"
 syslog = "5.0"
diff --git a/acmed/Cargo.toml b/acmed/Cargo.toml
index 92e8b98..c0bc081 100644
--- a/acmed/Cargo.toml
+++ b/acmed/Cargo.toml
@@ -12,9 +12,13 @@ include = ["src/**/*", "Cargo.toml", "LICENSE-*.txt"]
 build = "build.rs"
 publish = false
 
+[features]
+default = ["openssl_dyn"]
+openssl_dyn = ["acme_common/openssl_dyn", "attohttpc/tls"]
+
 [dependencies]
 acme_common = { path = "../acme_common" }
-attohttpc = { version = "0.15", features = ["charsets", "json"] }
+attohttpc = { version = "0.15", default-features = false, features = ["charsets", "json"] }
 clap = "2.32"
 handlebars = "3.0"
 log = "0.4"
diff --git a/tacd/Cargo.toml b/tacd/Cargo.toml
index 533a284..5db5348 100644
--- a/tacd/Cargo.toml
+++ b/tacd/Cargo.toml
@@ -11,6 +11,10 @@ license = "MIT OR Apache-2.0"
 include = ["src/**/*", "Cargo.toml", "LICENSE-*.txt"]
 publish = false
 
+[features]
+default = ["openssl_dyn"]
+openssl_dyn = ["acme_common/openssl_dyn"]
+
 [dependencies]
 acme_common = { path = "../acme_common" }
 clap = "2.32"