diff --git a/Cargo.lock b/Cargo.lock
index 20877964..35d020f5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -142,6 +142,7 @@ dependencies = [
  "serde_json",
  "serde_with",
  "tempfile",
+ "url",
 ]
 
 [[package]]
@@ -172,6 +173,15 @@ version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
+[[package]]
+name = "form_urlencoded"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e13624c2627564efccf4934284bdd98cbaa14e79b0b5a141218e507b3a823456"
+dependencies = [
+ "percent-encoding",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.12.3"
@@ -219,6 +229,16 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b9e0384b61958566e926dc50660321d12159025e767c18e043daf26b70104c39"
 
+[[package]]
+name = "idna"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "634d9b1461af396cad843f47fdba5597a4f9e6ddd4bfb6ff5d85028c25cb12f6"
+dependencies = [
+ "unicode-bidi",
+ "unicode-normalization",
+]
+
 [[package]]
 name = "indexmap"
 version = "1.9.3"
@@ -304,6 +324,12 @@ version = "1.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3fdb12b2476b595f9358c5161aa467c2438859caa136dec86c26fdd2efe17b92"
 
+[[package]]
+name = "percent-encoding"
+version = "2.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3148f5046208a5d56bcfc03053e3ca6334e51da8dfb19b6cdc8b306fae3283e"
+
 [[package]]
 name = "powerfmt"
 version = "0.2.0"
@@ -478,12 +504,53 @@ dependencies = [
  "time-core",
 ]
 
+[[package]]
+name = "tinyvec"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87cc5ceb3875bb20c2890005a4e226a4651264a5c75edb2421b52861a0a0cb50"
+dependencies = [
+ "tinyvec_macros",
+]
+
+[[package]]
+name = "tinyvec_macros"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
+
+[[package]]
+name = "unicode-bidi"
+version = "0.3.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "08f95100a766bf4f8f28f90d77e0a5461bbdb219042e7679bebe79004fed8d75"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
 
+[[package]]
+name = "unicode-normalization"
+version = "0.1.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c5713f0fc4b5db668a2ac63cdb7bb4469d8c9fed047b1d0292cc7b0ce2ba921"
+dependencies = [
+ "tinyvec",
+]
+
+[[package]]
+name = "url"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "31e6302e3bb753d46e83516cae55ae196fc0c309407cf11ab35cc51a4c2a4633"
+dependencies = [
+ "form_urlencoded",
+ "idna",
+ "percent-encoding",
+]
+
 [[package]]
 name = "wasm-bindgen"
 version = "0.2.91"
diff --git a/packages/dns-test/Cargo.toml b/packages/dns-test/Cargo.toml
index 0851b3e4..20b13d33 100644
--- a/packages/dns-test/Cargo.toml
+++ b/packages/dns-test/Cargo.toml
@@ -11,6 +11,7 @@ serde = { version = "1.0.196", features = ["derive"] }
 serde_json = "1.0.113"
 serde_with = "3.6.1"
 tempfile = "3.9.0"
+url = "2.5.0"
 
 [lib]
 doctest = false
diff --git a/packages/dns-test/src/container.rs b/packages/dns-test/src/container.rs
index 449f81d8..92550114 100644
--- a/packages/dns-test/src/container.rs
+++ b/packages/dns-test/src/container.rs
@@ -37,20 +37,20 @@ impl Container {
             .arg(&image_tag)
             .arg(docker_build_dir);
 
-        let srcdir = if let Implementation::Hickory { url } = implementation {
-            Some(url)
+        let repo = if let Implementation::Hickory(repo) = implementation {
+            Some(repo)
         } else {
             None
         };
 
         implementation.once().call_once(|| {
-            if let Some(srcdir) = srcdir {
+            if let Some(repo) = repo {
                 let mut cp_r = Command::new("git");
                 cp_r.args([
                     "clone",
                     "--depth",
                     "1",
-                    srcdir,
+                    repo.as_str(),
                     &docker_build_dir.join("src").display().to_string(),
                 ]);
 
diff --git a/packages/dns-test/src/lib.rs b/packages/dns-test/src/lib.rs
index 82d90851..75ea0f58 100644
--- a/packages/dns-test/src/lib.rs
+++ b/packages/dns-test/src/lib.rs
@@ -1,8 +1,12 @@
 //! A test framework for all things DNS
 
 use core::fmt;
+use std::borrow::Cow;
+use std::path::Path;
 use std::sync::Once;
 
+use url::Url;
+
 pub use crate::container::Network;
 pub use crate::fqdn::FQDN;
 pub use crate::resolver::Resolver;
@@ -24,7 +28,33 @@ pub mod zone_file;
 #[derive(Clone)]
 pub enum Implementation {
     Unbound,
-    Hickory { url: String },
+    Hickory(Repository<'static>),
+}
+
+#[derive(Clone)]
+pub struct Repository<'a> {
+    inner: Cow<'a, str>,
+}
+
+impl Repository<'_> {
+    fn as_str(&self) -> &str {
+        &self.inner
+    }
+}
+
+/// checks that `input` looks like a valid repository which can be either local or remote
+///
+/// # Panics
+///
+/// this function panics if `input` is not a local `Path` that exists or a well-formed URL
+#[allow(non_snake_case)]
+pub fn Repository(input: impl Into<Cow<'static, str>>) -> Repository<'static> {
+    let input = input.into();
+    assert!(
+        Path::new(&*input).exists() || Url::parse(&input).is_ok(),
+        "{input} is not a valid repository"
+    );
+    Repository { inner: input }
 }
 
 impl Implementation {
@@ -74,9 +104,7 @@ pub fn subject() -> Implementation {
 
         if subject.starts_with("hickory") {
             if let Some(url) = subject.strip_prefix("hickory ") {
-                Implementation::Hickory {
-                    url: url.to_string(),
-                }
+                Implementation::Hickory(Repository(url.to_string()))
             } else {
                 panic!("the syntax of DNS_TEST_SUBJECT is 'hickory $URL', e.g. 'hickory /tmp/hickory' or 'hickory https://github.com/owner/repo'")
             }