diff --git a/CHANGELOG.md b/CHANGELOG.md
index 03ad9f82..bd16a260 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+# 0.17.0 - 2023-06-29
+
+* `params` field in `Request` changed to a generic `RawValue` instead of an array.
+  [#108](https://github.com/apoelstra/rust-jsonrpc/pull/108)
+
 # 0.16.0 - 2023-06-29
 
 * Re-export the `minreq` crate when the feature is set
diff --git a/README.md b/README.md
index ece3c413..1b6ebe98 100644
--- a/README.md
+++ b/README.md
@@ -37,7 +37,7 @@ fn client(url: &str, user: &str, pass: &str) -> Result<Client, simple_http::Erro
 // Demonstrate an example JSON-RCP call against bitcoind.
 fn main() {
     let client = client("localhost:18443", "user", "pass").expect("failed to create client");
-    let request = client.build_request("uptime", &[]);
+    let request = client.build_request("uptime", None);
     let response = client.send_request(request).expect("send_request failed");
 
     // For other commands this would be a struct matching the returned json.
diff --git a/contrib/test.sh b/contrib/test.sh
index da2a9e42..ca335ba6 100755
--- a/contrib/test.sh
+++ b/contrib/test.sh
@@ -16,7 +16,11 @@ fi
 # Pin dependencies as required if we are using MSRV toolchain.
 if cargo --version | grep "1\.48"; then
     # 1.0.157 uses syn 2.0 which requires edition 2021
+    cargo update -p serde_json --precise 1.0.99
     cargo update -p serde --precise 1.0.156
+    cargo update -p quote --precise 1.0.30
+    cargo update -p proc-macro2 --precise 1.0.63
+    cargo update -p byteorder --precise 1.4.3
 fi
 
 # Make all cargo invocations verbose
diff --git a/fuzz/fuzz_targets/minreq_http.rs b/fuzz/fuzz_targets/minreq_http.rs
index 68eee3af..1ee87a96 100644
--- a/fuzz/fuzz_targets/minreq_http.rs
+++ b/fuzz/fuzz_targets/minreq_http.rs
@@ -21,7 +21,7 @@ fn do_test(data: &[u8]) {
             .build();
 
         let client = Client::with_transport(t);
-        let request = client.build_request("uptime", &[]);
+        let request = client.build_request("uptime", None);
         let _ = client.send_request(request);
     }
 }
diff --git a/fuzz/fuzz_targets/simple_http.rs b/fuzz/fuzz_targets/simple_http.rs
index b27cc6a0..7294b0f4 100644
--- a/fuzz/fuzz_targets/simple_http.rs
+++ b/fuzz/fuzz_targets/simple_http.rs
@@ -21,7 +21,7 @@ fn do_test(data: &[u8]) {
             .build();
 
         let client = Client::with_transport(t);
-        let request = client.build_request("uptime", &[]);
+        let request = client.build_request("uptime", None);
         let _ = client.send_request(request);
     }
 }
diff --git a/integration_test/src/main.rs b/integration_test/src/main.rs
index 43e7181f..4dd014ad 100644
--- a/integration_test/src/main.rs
+++ b/integration_test/src/main.rs
@@ -22,6 +22,8 @@ use backtrace::Backtrace;
 
 use jsonrpc::http::minreq_http;
 use jsonrpc::{Client, Request};
+use serde_json::json;
+use serde_json::value::to_raw_value;
 
 struct StdLogger;
 
@@ -113,6 +115,9 @@ fn main() {
 
     run_test!(test_get_network_info);
 
+    run_test!(test_get_block_hash_list);
+    run_test!(test_get_block_hash_named);
+
     // Print results
     println!("");
     println!("");
@@ -140,10 +145,46 @@ fn main() {
 fn test_get_network_info(cl: &Client) {
     let request = Request {
         method: "getnetworkinfo".into(),
-        params: &[],
+        params: None,
         id: serde_json::json!(1),
         jsonrpc: Some("2.0"),
     };
 
     let _ = cl.send_request(request).unwrap();
 }
+
+fn test_get_block_hash_list(cl: &Client) {
+    let param = json!([0]);
+    let raw_value = Some(to_raw_value(&param).unwrap());
+
+    let request = Request {
+        method: "getblockhash".into(),
+        params: raw_value.as_deref(),
+        id: serde_json::json!(2),
+        jsonrpc: Some("2.0"),
+    };
+
+    let resp = cl.send_request(request).unwrap();
+    assert_eq!(
+        resp.result.unwrap().to_string(),
+        "\"0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206\""
+    );
+}
+
+fn test_get_block_hash_named(cl: &Client) {
+    let param = json!({ "height": 0 });
+    let raw_value = Some(to_raw_value(&param).unwrap());
+
+    let request = Request {
+        method: "getblockhash".into(),
+        params: raw_value.as_deref(),
+        id: serde_json::json!(2),
+        jsonrpc: Some("2.0"),
+    };
+
+    let resp = cl.send_request(request).unwrap();
+    assert_eq!(
+        resp.result.unwrap().to_string(),
+        "\"0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206\""
+    );
+}
diff --git a/src/client.rs b/src/client.rs
index 5e900602..1e90f0d5 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -49,7 +49,7 @@ impl Client {
     ///
     /// To construct the arguments, one can use one of the shorthand methods
     /// [`crate::arg`] or [`crate::try_arg`].
-    pub fn build_request<'a>(&self, method: &'a str, params: &'a [Box<RawValue>]) -> Request<'a> {
+    pub fn build_request<'a>(&self, method: &'a str, params: Option<&'a RawValue>) -> Request<'a> {
         let nonce = self.nonce.fetch_add(1, atomic::Ordering::Relaxed);
         Request {
             method,
@@ -115,7 +115,7 @@ impl Client {
     pub fn call<R: for<'a> serde::de::Deserialize<'a>>(
         &self,
         method: &str,
-        args: &[Box<RawValue>],
+        args: Option<&RawValue>,
     ) -> Result<R, Error> {
         let request = self.build_request(method, args);
         let id = request.id.clone();
@@ -224,9 +224,9 @@ mod tests {
     fn sanity() {
         let client = Client::with_transport(DummyTransport);
         assert_eq!(client.nonce.load(sync::atomic::Ordering::Relaxed), 1);
-        let req1 = client.build_request("test", &[]);
+        let req1 = client.build_request("test", None);
         assert_eq!(client.nonce.load(sync::atomic::Ordering::Relaxed), 2);
-        let req2 = client.build_request("test", &[]);
+        let req2 = client.build_request("test", None);
         assert_eq!(client.nonce.load(sync::atomic::Ordering::Relaxed), 3);
         assert!(req1.id != req2.id);
     }
diff --git a/src/http/simple_http.rs b/src/http/simple_http.rs
index 5b216710..e143a62f 100644
--- a/src/http/simple_http.rs
+++ b/src/http/simple_http.rs
@@ -818,11 +818,11 @@ mod tests {
         let port = rx.recv().unwrap();
         let client =
             Client::simple_http(format!("localhost:{}", port).as_str(), None, None).unwrap();
-        let request = client.build_request("test_request", &[]);
+        let request = client.build_request("test_request", None);
         let result = client.send_request(request).unwrap();
         assert_eq!(result.id, Value::Number(Number::from(0)));
         thread::sleep(Duration::from_secs(1));
-        let request = client.build_request("test_request2", &[]);
+        let request = client.build_request("test_request2", None);
         let result2 = client.send_request(request)
             .expect("This second request should not be an Err like `Err(Transport(HttpResponseTooShort { actual: 0, needed: 12 }))`");
         assert_eq!(result2.id, Value::Number(Number::from(1)));
diff --git a/src/lib.rs b/src/lib.rs
index 73d19726..4d942adf 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -70,7 +70,7 @@ pub struct Request<'a> {
     /// The name of the RPC call.
     pub method: &'a str,
     /// Parameters to the RPC call.
-    pub params: &'a [Box<RawValue>],
+    pub params: Option<&'a RawValue>,
     /// Identifier for this request, which should appear in the response.
     pub id: serde_json::Value,
     /// jsonrpc field, MUST be "2.0".
@@ -123,7 +123,10 @@ impl Response {
 mod tests {
     use super::*;
 
-    use serde_json::value::RawValue;
+    use serde_json::{
+        json,
+        value::{to_raw_value, RawValue},
+    };
 
     #[test]
     fn response_is_none() {
@@ -219,4 +222,38 @@ mod tests {
             Test
         );
     }
+
+    #[test]
+    fn test_request_list() {
+        let list = json!([0]);
+        let raw_value = Some(to_raw_value(&list).unwrap());
+
+        let request = Request {
+            method: "list",
+            params: raw_value.as_deref(),
+            id: serde_json::json!(2),
+            jsonrpc: Some("2.0"),
+        };
+        assert_eq!(
+            serde_json::to_string(&request).unwrap(),
+            r#"{"method":"list","params":[0],"id":2,"jsonrpc":"2.0"}"#
+        );
+    }
+
+    #[test]
+    fn test_request_object() {
+        let object = json!({ "height": 0 });
+        let raw_value = Some(to_raw_value(&object).unwrap());
+
+        let request = Request {
+            method: "object",
+            params: raw_value.as_deref(),
+            id: serde_json::json!(2),
+            jsonrpc: Some("2.0"),
+        };
+        assert_eq!(
+            serde_json::to_string(&request).unwrap(),
+            r#"{"method":"object","params":{"height":0},"id":2,"jsonrpc":"2.0"}"#
+        );
+    }
 }
diff --git a/src/simple_tcp.rs b/src/simple_tcp.rs
index 27130e4e..f36600b0 100644
--- a/src/simple_tcp.rs
+++ b/src/simple_tcp.rs
@@ -134,7 +134,7 @@ mod tests {
         let addr = server.local_addr().unwrap();
         let dummy_req = Request {
             method: "arandommethod",
-            params: &[],
+            params: None,
             id: serde_json::Value::Number(4242242.into()),
             jsonrpc: Some("2.0"),
         };
diff --git a/src/simple_uds.rs b/src/simple_uds.rs
index a1afdf58..d05c48fd 100644
--- a/src/simple_uds.rs
+++ b/src/simple_uds.rs
@@ -137,7 +137,7 @@ mod tests {
         let server = UnixListener::bind(&socket_path).unwrap();
         let dummy_req = Request {
             method: "getinfo",
-            params: &[],
+            params: None,
             id: serde_json::Value::Number(111.into()),
             jsonrpc: Some("2.0"),
         };