diff --git a/Cargo.lock b/Cargo.lock
index e89696ad..c9e421a2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,24 +2,18 @@
 # It is not intended for manual editing.
 [[package]]
 name = "aho-corasick"
-version = "0.7.14"
+version = "0.7.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b476ce7103678b0c6d3d395dbbae31d48ff910bd28be979ba5d48c6351131d0d"
+checksum = "7404febffaa47dac81aa44dba71523c9d069b1bdc50a77db41195149e17f68e5"
 dependencies = [
  "memchr",
 ]
 
 [[package]]
 name = "anyhow"
-version = "1.0.33"
+version = "1.0.34"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a1fd36ffbb1fb7c834eac128ea8d0e310c5aeb635548f9d58861e1308d46e71c"
-
-[[package]]
-name = "arc-swap"
-version = "0.4.7"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4d25d88fd6b8041580a654f9d0c581a047baee2b3efee13275f2fc392fc75034"
+checksum = "bf8dcb5b4bbaa28653b647d8c77bd4ed40183b48882e130c1f1ffb73de069fd7"
 
 [[package]]
 name = "arrayref"
@@ -158,9 +152,9 @@ checksum = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
 
 [[package]]
 name = "blake2b_simd"
-version = "0.5.10"
+version = "0.5.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d8fb2d74254a3a0b5cac33ac9f8ed0e44aa50378d9dbb2e5d83bd21ed1dc2c8a"
+checksum = "afa748e348ad3be8263be728124b24a24f268266f6f5d58af9d75f6a40b5c587"
 dependencies = [
  "arrayref",
  "arrayvec",
@@ -279,9 +273,9 @@ dependencies = [
 
 [[package]]
 name = "crossterm"
-version = "0.18.1"
+version = "0.18.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cef9149b29071d44c9fb98fd9c27fcf74405bbdb761889ad6a03f36be93b0b15"
+checksum = "4e86d73f2a0b407b5768d10a8c720cf5d2df49a9efc10ca09176d201ead4b7fb"
 dependencies = [
  "bitflags",
  "crossterm_winapi",
@@ -479,6 +473,7 @@ dependencies = [
  "jsonrpc-core",
  "log",
  "lsp-types",
+ "once_cell",
  "pathdiff",
  "serde",
  "serde_json",
@@ -653,15 +648,15 @@ checksum = "7ffc5c5338469d4d3ea17d269fa8ea3512ad247247c30bd2df69e68309ed0a08"
 
 [[package]]
 name = "memchr"
-version = "2.3.3"
+version = "2.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3728d817d99e5ac407411fa471ff9800a778d88a24685968b36824eaf4bee400"
+checksum = "0ee1c47aaa256ecabcaea351eae4a9b01ef39ed810004e298d2511ed284b1525"
 
 [[package]]
 name = "mio"
-version = "0.7.4"
+version = "0.7.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8f1c83949125de4a582aa2da15ae6324d91cf6a58a70ea407643941ff98f558"
+checksum = "8962c171f57fcfffa53f4df1bb15ec4c8cf26a7569459c9ceb62d94aab0d9584"
 dependencies = [
  "libc",
  "log",
@@ -707,9 +702,9 @@ dependencies = [
 
 [[package]]
 name = "num-integer"
-version = "0.1.43"
+version = "0.1.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8d59457e662d541ba17869cf51cf177c0b5f0cbf476c66bdc90bf1edac4f875b"
+checksum = "d2cc698a63b549a70bc047073d2949cce27cd1c7b0a4a862d08a8031bc2801db"
 dependencies = [
  "autocfg",
  "num-traits",
@@ -717,9 +712,9 @@ dependencies = [
 
 [[package]]
 name = "num-traits"
-version = "0.2.12"
+version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ac267bcc07f48ee5f8935ab0d24f316fb722d7a1292e2913f0cc196b29ffd611"
+checksum = "9a64b1ec5cda2586e284722486d802acf1f7dbdc623e2bfc57e65ca1cd099290"
 dependencies = [
  "autocfg",
 ]
@@ -837,9 +832,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro-hack"
-version = "0.5.18"
+version = "0.5.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "99c605b9a0adc77b7211c6b1f722dcb613d68d66859a44f3d485a6da332b0598"
+checksum = "dbf0c48bc1d91375ae5c3cd81e3722dff1abcf81a30960240640d223f59fe0e5"
 
 [[package]]
 name = "proc-macro-nested"
@@ -884,9 +879,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.4.1"
+version = "1.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8963b85b8ce3074fecffde43b4b0dded83ce2f367dc8d363afc56679f3ee820b"
+checksum = "38cf2c13ed4745de91a5eb834e11c00bcc3709e773173b2ce4c56c9fbde04b9c"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -896,9 +891,9 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.6.20"
+version = "0.6.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8cab7a364d15cde1e505267766a2d3c4e22a843e1a601f0fa7564c0f82ced11c"
+checksum = "3b181ba2dcf07aaccad5448e8ead58db5b742cf85dfe035e2227f137a539a189"
 
 [[package]]
 name = "ropey"
@@ -997,11 +992,10 @@ dependencies = [
 
 [[package]]
 name = "signal-hook-registry"
-version = "1.2.1"
+version = "1.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a3e12110bc539e657a646068aaf5eb5b63af9d0c1f7b29c97113fad80e15f035"
+checksum = "ce32ea0c6c56d5eacaeb814fbed9960547021d3edd010ded1425f180536b20ab"
 dependencies = [
- "arc-swap",
  "libc",
 ]
 
@@ -1079,18 +1073,18 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "1.0.21"
+version = "1.0.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "318234ffa22e0920fe9a40d7b8369b5f649d490980cf7aadcf1eb91594869b42"
+checksum = "0e9ae34b84616eedaaf1e9dd6026dbe00dcafa92aa0c8077cb69df1fcfe5e53e"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.21"
+version = "1.0.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cae2447b6282786c3493999f40a9be2a6ad20cb8bd268b0a0dbf5a065535c0ab"
+checksum = "9ba20f23e85b10754cd195504aebf6a27e2e6cbe28c17778a0c930724628dd56"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1125,9 +1119,9 @@ checksum = "238ce071d267c5710f9d31451efec16c5ee22de34df17cc05e56cbc92e967117"
 
 [[package]]
 name = "tree-sitter"
-version = "0.17.0"
+version = "0.17.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70ee7370fec3aecde3862a7d64c571048f70a7298daef1815e8fc68b9de54b5c"
+checksum = "d18dcb776d3affaba6db04d11d645946d34a69b3172e588af96ce9fecd20faac"
 dependencies = [
  "cc",
  "regex",
diff --git a/helix-core/src/syntax.rs b/helix-core/src/syntax.rs
index f4826fb4..70d42c47 100644
--- a/helix-core/src/syntax.rs
+++ b/helix-core/src/syntax.rs
@@ -62,6 +62,10 @@ impl LanguageConfiguration {
             })
             .map(Option::as_ref)
     }
+
+    pub fn scope(&self) -> &str {
+        &self.scope
+    }
 }
 
 use once_cell::sync::Lazy;
diff --git a/helix-lsp/Cargo.toml b/helix-lsp/Cargo.toml
index 0c5d8b91..08216f59 100644
--- a/helix-lsp/Cargo.toml
+++ b/helix-lsp/Cargo.toml
@@ -9,6 +9,7 @@ edition = "2018"
 [dependencies]
 helix-core = { path = "../helix-core" }
 helix-view = { path = "../helix-view" }
+once_cell = "1.4"
 
 lsp-types = { version = "0.83", features = ["proposed"] }
 smol = "1.2"
diff --git a/helix-lsp/src/lib.rs b/helix-lsp/src/lib.rs
index 1ee8199f..8353ef7d 100644
--- a/helix-lsp/src/lib.rs
+++ b/helix-lsp/src/lib.rs
@@ -4,11 +4,15 @@ mod transport;
 pub use jsonrpc_core as jsonrpc;
 pub use lsp_types as lsp;
 
+pub use once_cell::sync::{Lazy, OnceCell};
+
 pub use client::Client;
 pub use lsp::{Position, Url};
 
 use thiserror::Error;
 
+use std::{collections::HashMap, sync::Arc};
+
 #[derive(Error, Debug)]
 pub enum Error {
     #[error("protocol error: {0}")]
@@ -62,3 +66,52 @@ impl Notification {
 }
 
 pub use jsonrpc::Call;
+
+type LanguageId = String;
+
+pub static REGISTRY: Lazy<Registry> = Lazy::new(Registry::init);
+
+pub struct Registry {
+    inner: HashMap<LanguageId, OnceCell<Arc<Client>>>,
+}
+
+impl Registry {
+    pub fn init() -> Self {
+        Self {
+            inner: HashMap::new(),
+        }
+    }
+
+    pub fn get(&self, id: &str, ex: &smol::Executor) -> Option<Arc<Client>> {
+        // TODO: use get_or_try_init and propagate the error
+        self.inner
+            .get(id)
+            .map(|cell| {
+                cell.get_or_init(|| {
+                    // TODO: lookup defaults for id (name, args)
+
+                    // initialize a new client
+                    let client = Client::start(&ex, "rust-analyzer", &[]);
+                    // TODO: also call initialize().await()
+                    Arc::new(client)
+                })
+            })
+            .cloned()
+    }
+}
+
+// REGISTRY = HashMap<LanguageId, Lazy/OnceCell<Arc<RwLock<Client>>>
+// spawn one server per language type, need to spawn one per workspace if server doesn't support
+// workspaces
+//
+// could also be a client per root dir
+//
+// storing a copy of Option<Arc<RwLock<Client>>> on Document would make the LSP client easily
+// accessible during edit/save callbacks
+//
+// the event loop needs to process all incoming streams, maybe we can just have that be a separate
+// task that's continually running and store the state on the client, then use read lock to
+// retrieve data during render
+// -> PROBLEM: how do you trigger an update on the editor side when data updates?
+//
+// -> The data updates should pull all events until we run out so we don't frequently re-render
diff --git a/helix-term/src/application.rs b/helix-term/src/application.rs
index cacfde56..141779ec 100644
--- a/helix-term/src/application.rs
+++ b/helix-term/src/application.rs
@@ -636,9 +636,17 @@ impl<'a> Application<'a> {
                 }
             }
             Some(Call::MethodCall(call)) => {
-                // TODO: need to make Result<Value, Error>
+                debug!("Method not found {}", call.method);
 
-                unimplemented!("{:?}", call)
+                self.language_server.reply(
+                    call.id,
+                    // TODO: make a Into trait that can cast to Err(jsonrpc::Error)
+                    Err(helix_lsp::jsonrpc::Error {
+                        code: helix_lsp::jsonrpc::ErrorCode::MethodNotFound,
+                        message: "Method not found".to_string(),
+                        data: None,
+                    }),
+                );
             }
             _ => unreachable!(),
         }
diff --git a/helix-view/src/document.rs b/helix-view/src/document.rs
index 1587de8b..e8f311c5 100644
--- a/helix-view/src/document.rs
+++ b/helix-view/src/document.rs
@@ -25,6 +25,8 @@ pub struct Document {
 
     /// Tree-sitter AST tree
     pub syntax: Option<Syntax>,
+    /// Corresponding language scope name. Usually `source.<lang>`.
+    pub language: Option<String>,
 
     /// Pending changes since last history commit.
     pub changes: ChangeSet,
@@ -64,6 +66,7 @@ impl Document {
             mode: Mode::Normal,
             restore_cursor: false,
             syntax: None,
+            language: None,
             changes,
             old_state,
             diagnostics: Vec::new(),
@@ -73,6 +76,7 @@ impl Document {
     }
 
     // TODO: passing scopes here is awkward
+    // TODO: async fn?
     pub fn load(path: PathBuf, scopes: &[String]) -> Result<Self, Error> {
         use std::{env, fs::File, io::BufReader};
         let _current_dir = env::current_dir()?;
@@ -90,6 +94,15 @@ impl Document {
             let syntax = Syntax::new(&doc.state.doc, highlight_config.clone());
 
             doc.syntax = Some(syntax);
+            // TODO: maybe just keep an Arc<> pointer to the language_config?
+            doc.language = Some(language_config.scope().to_string());
+
+            // TODO: this ties lsp support to tree-sitter enabled languages for now. Language
+            // config should use Option<HighlightConfig> to let us have non-tree-sitter configs.
+
+            // TODO: circular dep: view <-> lsp
+            // helix_lsp::REGISTRY;
+            // view should probably depend on lsp
         };
 
         // canonicalize path to absolute value
@@ -98,6 +111,8 @@ impl Document {
         Ok(doc)
     }
 
+    // TODO: do we need some way of ensuring two save operations on the same doc can't run at once?
+    // or is that handled by the OS/async layer
     pub fn save(&self) -> impl Future<Output = Result<(), anyhow::Error>> {
         // we clone and move text + path into the future so that we asynchronously save the current
         // state without blocking any further edits.