diff --git a/proto/anki/launcher.proto b/proto/anki/launcher.proto
new file mode 100644
index 000000000..d16bc760c
--- /dev/null
+++ b/proto/anki/launcher.proto
@@ -0,0 +1,87 @@
+// Copyright: Ankitects Pty Ltd and contributors
+// License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+
+syntax = "proto3";
+
+package anki.launcher;
+
+import "anki/generic.proto";
+
+service LauncherService {
+  rpc I18nResources(I18nResourcesRequest) returns (generic.Json);
+  rpc GetLangs(generic.Empty) returns (GetLangsResponse);
+  rpc SetLang(generic.String) returns (generic.Empty);
+  rpc GetVersions(generic.Empty) returns (GetVersionsResponse);
+  rpc ChooseVersion(ChooseVersionRequest) returns (ChooseVersionResponse);
+  rpc GetOptions(generic.Empty) returns (Options);
+  rpc GetMirrors(generic.Empty) returns (GetMirrorsResponse);
+  rpc WindowReady(generic.Empty) returns (generic.Empty);
+  rpc ZoomWebview(ZoomWebviewRequest) returns (generic.Empty);
+}
+
+// TODO: this should not be necessary
+service BackendLauncherService {}
+
+// TODO: codegen
+enum Event {
+  TERM_INPUT = 0;
+  WINDOWS_READY = 1;
+}
+
+message I18nResourcesRequest {
+  repeated string modules = 1;
+}
+
+message I18nResourcesResponse {
+  repeated string langs = 1;
+  repeated string resources = 2;
+}
+
+message GetLangsResponse {
+  message Pair {
+    string name = 1;
+    string locale = 2;
+  }
+  string user_locale = 1;
+  repeated Pair langs = 2;
+}
+
+enum Mirror {
+  DISABLED = 0;
+  CHINA = 1;
+}
+
+message GetMirrorsResponse {
+  message Pair {
+    Mirror mirror = 1;
+    string name = 2;
+  }
+  repeated Pair mirrors = 1;
+}
+
+message Options {
+  bool allow_betas = 1;
+  bool download_caching = 2;
+  Mirror mirror = 3;
+}
+
+message GetVersionsResponse {
+  repeated string all = 1;
+  repeated string latest = 2;
+  optional string current = 3;
+  optional string previous = 4;
+}
+
+message ChooseVersionRequest {
+  string version = 1;
+  bool keep_existing = 2;
+  Options options = 3;
+}
+
+message ChooseVersionResponse {
+  string version = 1;
+}
+
+message ZoomWebviewRequest {
+  float scale_factor = 1;
+}
diff --git a/rslib/proto/build.rs b/rslib/proto/build.rs
index feb84d410..4ede26409 100644
--- a/rslib/proto/build.rs
+++ b/rslib/proto/build.rs
@@ -14,8 +14,16 @@ fn main() -> Result<()> {
 
     let pool = rust::write_rust_protos(descriptors_path)?;
     let (_, services) = get_services(&pool);
+
+    let (services, launcher_services): (Vec<_>, Vec<_>) = services
+        .into_iter()
+        .partition(|s| !s.name.trim_start_matches("Backend").starts_with("Launcher"));
+
     python::write_python_interface(&services)?;
-    typescript::write_ts_interface(&services)?;
+    typescript::write_ts_interface(&services, false)?;
+
+    // for launcher-gui
+    typescript::write_ts_interface(&launcher_services, true)?;
 
     Ok(())
 }
diff --git a/rslib/proto/rust.rs b/rslib/proto/rust.rs
index 85834f19f..61e12ba61 100644
--- a/rslib/proto/rust.rs
+++ b/rslib/proto/rust.rs
@@ -49,6 +49,7 @@ pub fn write_rust_protos(descriptors_path: PathBuf) -> Result<DescriptorPool> {
             "ImportAnkiPackageUpdateCondition",
             "#[derive(serde::Deserialize, serde::Serialize)]",
         )
+        .type_attribute(".anki.launcher.Mirror", "#[derive(strum::EnumIter)]")
         .compile_protos(paths.as_slice(), &[proto_dir])
         .context("prost build")?;
 
diff --git a/rslib/proto/src/lib.rs b/rslib/proto/src/lib.rs
index 86d7d1580..7396192e3 100644
--- a/rslib/proto/src/lib.rs
+++ b/rslib/proto/src/lib.rs
@@ -37,3 +37,4 @@ protobuf!(stats, "stats");
 protobuf!(sync, "sync");
 protobuf!(tags, "tags");
 protobuf!(ankihub, "ankihub");
+protobuf!(launcher, "launcher");
diff --git a/rslib/proto/typescript.rs b/rslib/proto/typescript.rs
index 4e941a0ca..66cc7e590 100644
--- a/rslib/proto/typescript.rs
+++ b/rslib/proto/typescript.rs
@@ -13,7 +13,7 @@ use anyhow::Result;
 use inflections::Inflect;
 use itertools::Itertools;
 
-pub(crate) fn write_ts_interface(services: &[BackendService]) -> Result<()> {
+pub(crate) fn write_ts_interface(services: &[BackendService], is_launcher: bool) -> Result<()> {
     let root = Path::new("../../out/ts/lib/generated");
     create_dir_all(root)?;
 
@@ -29,13 +29,17 @@ pub(crate) fn write_ts_interface(services: &[BackendService]) -> Result<()> {
             let method = MethodDetails::from_method(method);
             record_referenced_type(&mut referenced_packages, &method.input_type);
             record_referenced_type(&mut referenced_packages, &method.output_type);
-            write_ts_method(&method, &mut ts_out);
+            write_ts_method(&method, &mut ts_out, is_launcher);
         }
     }
 
     let imports = imports(referenced_packages);
     write_file_if_changed(
-        root.join("backend.ts"),
+        root.join(if is_launcher {
+            "backend-launcher.ts"
+        } else {
+            "backend.ts"
+        }),
         format!("{}{}{}", ts_header(), imports, ts_out),
     )?;
 
@@ -75,12 +79,19 @@ fn write_ts_method(
         comments,
     }: &MethodDetails,
     out: &mut String,
+    is_launcher: bool,
 ) {
     let comments = format_comments(comments);
+    let proto_method_name = method_name;
+    let options = if is_launcher {
+        "{ ...options, customProtocol: true }"
+    } else {
+        "options"
+    };
     writeln!(
         out,
         r#"{comments}export async function {method_name}(input: PlainMessage<{input_type}>, options?: PostProtoOptions): Promise<{output_type}> {{
-        return await postProto("{method_name}", new {input_type}(input), {output_type}, options);
+        return await postProto("{proto_method_name}", new {input_type}(input), {output_type}, {options});
 }}"#
     ).unwrap()
 }
diff --git a/rslib/rust_interface.rs b/rslib/rust_interface.rs
index 6861df7dc..fb3a0ec96 100644
--- a/rslib/rust_interface.rs
+++ b/rslib/rust_interface.rs
@@ -20,14 +20,20 @@ pub fn write_rust_interface(pool: &DescriptorPool) -> Result<()> {
     let mut buf = String::new();
     buf.push_str("use crate::error::Result; use prost::Message;");
 
+    // TODO: we're misusing this for the launcher
     let (col_services, backend_services) = get_services(pool);
     let col_services = col_services
         .into_iter()
-        .filter(|s| s.name != "FrontendService")
+        .filter(|s| !matches!(&*s.name, "FrontendService" | "LauncherService"))
         .collect_vec();
     let backend_services = backend_services
         .into_iter()
-        .filter(|s| s.name != "BackendFrontendService")
+        .filter(|s| {
+            !matches!(
+                &*s.name,
+                "BackendFrontendService" | "BackendLauncherService"
+            )
+        })
         .collect_vec();
 
     render_collection_services(&col_services, &mut buf)?;