diff --git a/Cargo.lock b/Cargo.lock
index ce9727a50..a51896d45 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -30,6 +30,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5a15f179cd60c4584b8a8c596927aadc462e27f2ca70c04e0071964a73ba7a75"
 dependencies = [
  "cfg-if",
+ "getrandom 0.3.1",
  "once_cell",
  "version_check",
  "zerocopy",
@@ -126,9 +127,9 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.16.0"
+version = "3.18.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "79296716171880943b8470b5f8d03aa55eb2e645a4874bdbb28adb49162e012c"
+checksum = "793db76d6187cd04dff33004d8e6c9cc4e05cd330500379d2394209271b4aeee"
 
 [[package]]
 name = "byteorder"
@@ -138,9 +139,9 @@ checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
 
 [[package]]
 name = "bytes"
-version = "1.7.1"
+version = "1.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8318a53db07bb3f8dca91a600466bdb3f2eaadeedfdbcf02e1accbad9271ba50"
+checksum = "d71b6127be86fdcfddb610f7182ac57211d4b18a3e9c82eb2d17662f2227ad6a"
 
 [[package]]
 name = "cassowary"
@@ -417,6 +418,18 @@ version = "2.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e8c02a5121d4ea3eb16a80748c74f5549a5665e4c21333c6098f283870fbdea6"
 
+[[package]]
+name = "faststr"
+version = "0.2.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a6503af7917fea18ffef8f7e8553fb8dff89e2e6837e94e09dd7fb069c82d62c"
+dependencies = [
+ "bytes",
+ "rkyv",
+ "serde",
+ "simdutf8",
+]
+
 [[package]]
 name = "fern"
 version = "0.7.1"
@@ -1444,6 +1457,7 @@ dependencies = [
  "log",
  "serde",
  "serde_json",
+ "sonic-rs",
  "thiserror 2.0.12",
  "tokio",
 ]
@@ -1497,6 +1511,7 @@ dependencies = [
  "serde",
  "serde_json",
  "slotmap",
+ "sonic-rs",
  "thiserror 2.0.12",
  "tokio",
  "tokio-stream",
@@ -1942,10 +1957,11 @@ dependencies = [
 
 [[package]]
 name = "js-sys"
-version = "0.3.70"
+version = "0.3.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1868808506b929d7b0cfa8f75951347aa71bb21144b7791bae35d9bccfcfe37a"
+checksum = "1cfaf33c695fc6e08064efbc1f72ec937429614f25eef83af942d0e227c3a28f"
 dependencies = [
+ "once_cell",
  "wasm-bindgen",
 ]
 
@@ -2085,6 +2101,26 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "munge"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9e22e7961c873e8b305b176d2a4e1d41ce7ba31bc1c52d2a107a89568ec74c55"
+dependencies = [
+ "munge_macro",
+]
+
+[[package]]
+name = "munge_macro"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0ac7d860b767c6398e88fe93db73ce53eb496057aa6895ffa4d60cb02e1d1c6b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "nucleo"
 version = "0.5.0"
@@ -2232,6 +2268,26 @@ dependencies = [
  "parking_lot",
 ]
 
+[[package]]
+name = "ptr_meta"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe9e76f66d3f9606f44e45598d155cb13ecf09f4a28199e48daf8c8fc937ea90"
+dependencies = [
+ "ptr_meta_derive",
+]
+
+[[package]]
+name = "ptr_meta_derive"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca414edb151b4c8d125c12566ab0d74dc9cdba36fb80eb7b848c15f495fd32d1"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "pulldown-cmark"
 version = "0.13.0"
@@ -2261,6 +2317,15 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rancor"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "caf5f7161924b9d1cea0e4cabc97c372cea92b5f927fc13c6bca67157a0ad947"
+dependencies = [
+ "ptr_meta",
+]
+
 [[package]]
 name = "rand"
 version = "0.8.5"
@@ -2308,6 +2373,26 @@ dependencies = [
  "bitflags",
 ]
 
+[[package]]
+name = "ref-cast"
+version = "1.0.24"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4a0ae411dbe946a674d89546582cea4ba2bb8defac896622d6496f14c23ba5cf"
+dependencies = [
+ "ref-cast-impl",
+]
+
+[[package]]
+name = "ref-cast-impl"
+version = "1.0.24"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1165225c21bff1f3bbce98f5a1f889949bc902d3575308cc7b0de30b4f6d27c7"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "regex"
 version = "1.11.1"
@@ -2350,6 +2435,41 @@ version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"
 
+[[package]]
+name = "rend"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a35e8a6bf28cd121053a66aa2e6a2e3eaffad4a60012179f0e864aa5ffeff215"
+
+[[package]]
+name = "rkyv"
+version = "0.8.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e147371c75553e1e2fcdb483944a8540b8438c31426279553b9a8182a9b7b65"
+dependencies = [
+ "bytes",
+ "hashbrown 0.15.4",
+ "indexmap",
+ "munge",
+ "ptr_meta",
+ "rancor",
+ "rend",
+ "rkyv_derive",
+ "tinyvec",
+ "uuid",
+]
+
+[[package]]
+name = "rkyv_derive"
+version = "0.8.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "246b40ac189af6c675d124b802e8ef6d5246c53e17367ce9501f8f66a81abb7a"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "ropey"
 version = "1.6.1"
@@ -2392,6 +2512,12 @@ dependencies = [
  "windows-sys 0.59.0",
 ]
 
+[[package]]
+name = "rustversion"
+version = "1.0.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a0d197bd2c9dc6e53b84da9556a69ba4cdfab8619eb41a8bd1cc2027a0f6b1d"
+
 [[package]]
 name = "ryu"
 version = "1.0.18"
@@ -2529,6 +2655,12 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "simdutf8"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3a9fe34e3e7a50316060351f37187a3f546bce95496156754b601a5fa71b76e"
+
 [[package]]
 name = "slab"
 version = "0.4.9"
@@ -2580,6 +2712,45 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "sonic-number"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a8a74044c092f4f43ca7a6cfd62854cf9fb5ac8502b131347c990bf22bef1dfe"
+dependencies = [
+ "cfg-if",
+]
+
+[[package]]
+name = "sonic-rs"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "93070f7e7c0d7ec7d08406b1b407234af30420320fd854f304029e3c6db4a899"
+dependencies = [
+ "ahash",
+ "bumpalo",
+ "bytes",
+ "cfg-if",
+ "faststr",
+ "itoa",
+ "ref-cast",
+ "ryu",
+ "serde",
+ "simdutf8",
+ "sonic-number",
+ "sonic-simd",
+ "thiserror 2.0.12",
+]
+
+[[package]]
+name = "sonic-simd"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b421f7b6aa4a5de8f685aaf398dfaa828346ee639d2b1c1061ab43d40baa6223"
+dependencies = [
+ "cfg-if",
+]
+
 [[package]]
 name = "stable_deref_trait"
 version = "1.2.0"
@@ -2928,6 +3099,16 @@ version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b6c140620e7ffbb22c2dee59cafe6084a59b5ffc27a8859a5f0d494b5d52b6be"
 
+[[package]]
+name = "uuid"
+version = "1.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3cf4199d1e5d15ddd86a694e4d0dffa9c323ce759fea589f00fef9d81cc1931d"
+dependencies = [
+ "js-sys",
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "version_check"
 version = "0.9.5"
@@ -2961,24 +3142,24 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.93"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a82edfc16a6c469f5f44dc7b571814045d60404b55a0ee849f9bcfa2e63dd9b5"
+checksum = "1edc8929d7499fc4e8f0be2262a241556cfc54a0bea223790e71446f2aab1ef5"
 dependencies = [
  "cfg-if",
  "once_cell",
+ "rustversion",
  "wasm-bindgen-macro",
 ]
 
 [[package]]
 name = "wasm-bindgen-backend"
-version = "0.2.93"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9de396da306523044d3302746f1208fa71d7532227f15e347e2d93e4145dd77b"
+checksum = "2f0a0651a5c2bc21487bde11ee802ccaf4c51935d0d3d42a6101f98161700bc6"
 dependencies = [
  "bumpalo",
  "log",
- "once_cell",
  "proc-macro2",
  "quote",
  "syn",
@@ -2987,9 +3168,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.93"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "585c4c91a46b072c92e908d99cb1dcdf95c5218eeb6f3bf1efa991ee7a68cccf"
+checksum = "7fe63fc6d09ed3792bd0897b314f53de8e16568c2b3f7982f468c0bf9bd0b407"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -2997,9 +3178,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.93"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "afc340c74d9005395cf9dd098506f7f44e38f2b4a21c6aaacf9a105ea5e1e836"
+checksum = "8ae87ea40c9f689fc23f209965b6fb8a99ad69aeeb0231408be24920604395de"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -3010,9 +3191,12 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.93"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c62a0a307cb4a311d3a07867860911ca130c3494e8c2719593806c08bc5d0484"
+checksum = "1a05d73b933a847d6cccdda8f838a22ff101ad9bf93e33684f39c1f5f0eece3d"
+dependencies = [
+ "unicode-ident",
+]
 
 [[package]]
 name = "which"
diff --git a/Cargo.toml b/Cargo.toml
index 770062286..18a7565e6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -47,6 +47,7 @@ unicode-segmentation = "1.2"
 ropey = { version = "1.6.1", default-features = false, features = ["simd"] }
 foldhash = "0.1"
 parking_lot = "0.12"
+sonic-rs = "0.5.1"
 
 [workspace.package]
 version = "25.1.1"
diff --git a/helix-dap/Cargo.toml b/helix-dap/Cargo.toml
index d67932afb..8e49ac634 100644
--- a/helix-dap/Cargo.toml
+++ b/helix-dap/Cargo.toml
@@ -22,6 +22,7 @@ serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 tokio = { version = "1", features = ["rt", "rt-multi-thread", "io-util", "io-std", "time", "process", "macros", "fs", "parking_lot", "net", "sync"] }
 thiserror.workspace = true
+sonic-rs.workspace = true
 
 [dev-dependencies]
 fern = "0.7"
diff --git a/helix-dap/src/lib.rs b/helix-dap/src/lib.rs
index b0605c4f0..14465f3be 100644
--- a/helix-dap/src/lib.rs
+++ b/helix-dap/src/lib.rs
@@ -12,7 +12,7 @@ use thiserror::Error;
 #[derive(Error, Debug)]
 pub enum Error {
     #[error("failed to parse: {0}")]
-    Parse(#[from] serde_json::Error),
+    Parse(Box<dyn std::error::Error + Send + Sync>),
     #[error("IO Error: {0}")]
     IO(#[from] std::io::Error),
     #[error("request {0} timed out")]
@@ -28,6 +28,18 @@ pub enum Error {
 }
 pub type Result<T> = core::result::Result<T, Error>;
 
+impl From<serde_json::Error> for Error {
+    fn from(value: serde_json::Error) -> Self {
+        Self::Parse(Box::new(value))
+    }
+}
+
+impl From<sonic_rs::Error> for Error {
+    fn from(value: sonic_rs::Error) -> Self {
+        Self::Parse(Box::new(value))
+    }
+}
+
 #[derive(Debug)]
 pub enum Request {
     RunInTerminal(<requests::RunInTerminal as types::Request>::Arguments),
diff --git a/helix-dap/src/transport.rs b/helix-dap/src/transport.rs
index 6911e4e72..78bc00eb5 100644
--- a/helix-dap/src/transport.rs
+++ b/helix-dap/src/transport.rs
@@ -125,11 +125,11 @@ impl Transport {
         info!("<- DAP {}", msg);
 
         // try parsing as output (server response) or call (server request)
-        let output: serde_json::Result<Payload> = serde_json::from_str(msg);
+        let output: Payload = sonic_rs::from_slice(content)?;
 
         content.clear();
 
-        Ok(output?)
+        Ok(output)
     }
 
     async fn recv_server_error(
diff --git a/helix-lsp/Cargo.toml b/helix-lsp/Cargo.toml
index 83e37a982..b81742b22 100644
--- a/helix-lsp/Cargo.toml
+++ b/helix-lsp/Cargo.toml
@@ -31,3 +31,4 @@ parking_lot.workspace = true
 arc-swap = "1"
 slotmap.workspace = true
 thiserror.workspace = true
+sonic-rs.workspace = true
diff --git a/helix-lsp/src/lib.rs b/helix-lsp/src/lib.rs
index 567e8a702..81b881593 100644
--- a/helix-lsp/src/lib.rs
+++ b/helix-lsp/src/lib.rs
@@ -37,7 +37,7 @@ pub enum Error {
     #[error("protocol error: {0}")]
     Rpc(#[from] jsonrpc::Error),
     #[error("failed to parse: {0}")]
-    Parse(#[from] serde_json::Error),
+    Parse(Box<dyn std::error::Error + Send + Sync>),
     #[error("IO Error: {0}")]
     IO(#[from] std::io::Error),
     #[error("request {0} timed out")]
@@ -52,6 +52,18 @@ pub enum Error {
     Other(#[from] anyhow::Error),
 }
 
+impl From<serde_json::Error> for Error {
+    fn from(value: serde_json::Error) -> Self {
+        Self::Parse(Box::new(value))
+    }
+}
+
+impl From<sonic_rs::Error> for Error {
+    fn from(value: sonic_rs::Error) -> Self {
+        Self::Parse(Box::new(value))
+    }
+}
+
 #[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
 pub enum OffsetEncoding {
     /// UTF-8 code units aka bytes
diff --git a/helix-lsp/src/transport.rs b/helix-lsp/src/transport.rs
index 088c617b7..2a849567a 100644
--- a/helix-lsp/src/transport.rs
+++ b/helix-lsp/src/transport.rs
@@ -98,7 +98,7 @@ impl Transport {
             buffer.clear();
             if reader.read_line(buffer).await? == 0 {
                 return Err(Error::StreamClosed);
-            };
+            }
 
             // debug!("<- header {:?}", buffer);
 
@@ -134,11 +134,11 @@ impl Transport {
         info!("{language_server_name} <- {msg}");
 
         // try parsing as output (server response) or call (server request)
-        let output: serde_json::Result<ServerMessage> = serde_json::from_str(msg);
+        let output: ServerMessage = sonic_rs::from_slice(content)?;
 
         content.clear();
 
-        Ok(output?)
+        Ok(output)
     }
 
     async fn recv_server_error(