diff --git a/engine/Cargo.lock b/engine/Cargo.lock
index f14f4fa4e8..b5ebc998e1 100644
--- a/engine/Cargo.lock
+++ b/engine/Cargo.lock
@@ -1058,6 +1058,19 @@ dependencies = [
  "uuid",
 ]
 
+[[package]]
+name = "baml-router"
+version = "0.88.0"
+dependencies = [
+ "axum",
+ "console_error_panic_hook",
+ "serde",
+ "serde_json",
+ "tower-service",
+ "worker",
+ "worker-macros",
+]
+
 [[package]]
 name = "baml-rpc"
 version = "0.0.1"
@@ -3583,9 +3596,9 @@ checksum = "8b23360e99b8717f20aaa4598f5a6541efbe30630039fbc7706cf954a87947ae"
 
 [[package]]
 name = "js-sys"
-version = "0.3.69"
+version = "0.3.70"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "29c15563dc2726973df627357ce0c9ddddbea194836909d655df6a75d2cf296d"
+checksum = "1868808506b929d7b0cfa8f75951347aa71bb21144b7791bae35d9bccfcfe37a"
 dependencies = [
  "wasm-bindgen",
 ]
@@ -5481,6 +5494,17 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "serde-wasm-bindgen"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f3b143e2833c57ab9ad3ea280d21fd34e285a42837aeb0ee301f4f41890fa00e"
+dependencies = [
+ "js-sys",
+ "serde",
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "serde-wasm-bindgen"
 version = "0.6.5"
@@ -6644,19 +6668,20 @@ checksum = "b8dad83b4f25e74f184f64c43b150b91efe7647395b42289f38e50566d82855b"
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.92"
+version = "0.2.93"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4be2531df63900aeb2bca0daaaddec08491ee64ceecbee5076636a3b026795a8"
+checksum = "a82edfc16a6c469f5f44dc7b571814045d60404b55a0ee849f9bcfa2e63dd9b5"
 dependencies = [
  "cfg-if",
+ "once_cell",
  "wasm-bindgen-macro",
 ]
 
 [[package]]
 name = "wasm-bindgen-backend"
-version = "0.2.92"
+version = "0.2.93"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "614d787b966d3989fa7bb98a654e369c762374fd3213d212cfc0251257e747da"
+checksum = "9de396da306523044d3302746f1208fa71d7532227f15e347e2d93e4145dd77b"
 dependencies = [
  "bumpalo",
  "log",
@@ -6681,9 +6706,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.92"
+version = "0.2.93"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a1f8823de937b71b9460c0c34e25f3da88250760bec0ebac694b49997550d726"
+checksum = "585c4c91a46b072c92e908d99cb1dcdf95c5218eeb6f3bf1efa991ee7a68cccf"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -6691,9 +6716,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.92"
+version = "0.2.93"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e94f17b526d0a461a191c78ea52bbce64071ed5c04c9ffe424dcb38f74171bb7"
+checksum = "afc340c74d9005395cf9dd098506f7f44e38f2b4a21c6aaacf9a105ea5e1e836"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -6704,9 +6729,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.92"
+version = "0.2.93"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "af190c94f2773fdb3729c55b007a722abb5384da03bc0986df4c289bf5567e96"
+checksum = "c62a0a307cb4a311d3a07867860911ca130c3494e8c2719593806c08bc5d0484"
 
 [[package]]
 name = "wasm-bindgen-test"
@@ -6773,9 +6798,9 @@ dependencies = [
 
 [[package]]
 name = "web-sys"
-version = "0.3.69"
+version = "0.3.70"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "77afa9a11836342370f4817622a2f0f418b134426d91a82dfb48f532d2ec13ef"
+checksum = "26fdeaafd9bd129f65e7c031593c24d62186301e0c72c8978fa1678be7d532c0"
 dependencies = [
  "js-sys",
  "wasm-bindgen",
@@ -7062,6 +7087,81 @@ dependencies = [
  "bitflags 2.9.0",
 ]
 
+[[package]]
+name = "worker"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "727789ca7eff9733efbea9d0e97779edc1cf1926e98aee7d7d8afe32805458aa"
+dependencies = [
+ "async-trait",
+ "axum",
+ "bytes",
+ "chrono",
+ "futures-channel",
+ "futures-util",
+ "http 1.1.0",
+ "http-body 1.0.1",
+ "js-sys",
+ "matchit",
+ "pin-project",
+ "serde",
+ "serde-wasm-bindgen 0.6.5",
+ "serde_json",
+ "serde_urlencoded",
+ "tokio",
+ "url",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "wasm-streams",
+ "web-sys",
+ "worker-kv",
+ "worker-macros",
+ "worker-sys",
+]
+
+[[package]]
+name = "worker-kv"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f06d4d1416a9f8346ee9123b0d9a11b3cfa38e6cfb5a139698017d1597c4d41"
+dependencies = [
+ "js-sys",
+ "serde",
+ "serde-wasm-bindgen 0.5.0",
+ "serde_json",
+ "thiserror 1.0.62",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+]
+
+[[package]]
+name = "worker-macros"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7d625c24570ba9207a2617476013335f28a95cbe513e59bb814ffba092a18058"
+dependencies = [
+ "async-trait",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.87",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "wasm-bindgen-macro-support",
+ "worker-sys",
+]
+
+[[package]]
+name = "worker-sys"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34563340d41016b4381257c5a16b0d2bc590dbe00500ecfbebcaa16f5f85ce90"
+dependencies = [
+ "cfg-if",
+ "js-sys",
+ "wasm-bindgen",
+ "web-sys",
+]
+
 [[package]]
 name = "write16"
 version = "1.0.0"
diff --git a/engine/Cargo.toml b/engine/Cargo.toml
index b802113093..018f27b091 100644
--- a/engine/Cargo.toml
+++ b/engine/Cargo.toml
@@ -1,131 +1,202 @@
 [workspace]
-resolver = "2"
 members = [
-  "baml-lib/*",
-  "baml-lsp-types",
-  "baml-rpc",
-  "baml-runtime",
-  "baml-schema-wasm",
-  "bstd",
-  "cli",
-  "language_client_codegen",
-  "language_client_python",
-  "language_client_ruby/ext/ruby_ffi",
-  "language_client_typescript",
-  "language_server",
-  "language_client_cffi",
-  "sandbox",
+    "baml-lib/*",
+    "baml-lsp-types",
+    "baml-router",
+    "baml-rpc",
+    "baml-runtime",
+    "baml-schema-wasm",
+    "bstd",
+    "cli",
+    "language_client_cffi",
+    "language_client_codegen",
+    "language_client_python",
+    "language_client_ruby/ext/ruby_ffi",
+    "language_client_typescript",
+    "language_server",
+    "sandbox",
 ]
 default-members = [
-  "baml-lsp-types",
-  "baml-lib/*",
-  "baml-rpc",
-  "baml-runtime",
-  # Disabled by default: --features no_wasm and --features wasm are mutually exclusive
-  # Building baml-schema-wasm in combination with everything else triggers feature unification,
-  # and it's OK to not build this by default because we have to build ts separately (this may
-  # also have something to do with resolver=2 and how duplicate dep builds are handled)
-  # "baml-schema-wasm",
-  "bstd",
-  "cli",
-  "language_client_cffi",
-  "language_client_codegen",
-  "language_client_python",
-  "language_client_ruby/ext/ruby_ffi",
-  "language_client_typescript",
-  "language_server",
+    "baml-lsp-types",
+    "baml-lib/*",
+    "baml-rpc",
+    "baml-runtime",
+    "bstd",
+    "cli",
+    "language_client_cffi",
+    "language_client_codegen",
+    "language_client_python",
+    "language_client_ruby/ext/ruby_ffi",
+    "language_client_typescript",
+    "language_server",
 ]
+resolver = "2"
+
+[workspace.metadata.workspaces]
+allow_branch = "canary"
+
+[workspace.package]
+version = "0.88.0"
+authors = ["Boundary <contact@boundaryml.com>"]
+description = "BAML Toolchain"
+license-file = "LICENSE"
 
 [workspace.dependencies]
-lsp-server = { version = "0.7.6" }
-lsp-types = { version = "0.95.0" }
 anyhow = "1.0"
 askama = "0.12.1"
-baml-cli = { path = "cli" }
-baml-types = { path = "baml-lib/baml-types" }
-baml-log = { path = "baml-lib/baml-log" }
 base64 = "0.22.1"
-bstd = { path = "bstd" }
 bytes = "1.6.0"
 cfg-if = "1.0.0"
-clap = { version = "4.4.6", features = ["cargo", "derive"] }
 dashmap = "5.5.3"
 derive-new = "0.7"
 derive_builder = "0.20.0"
-derive_more = { version = "0.99.18", features = ["constructor"] }
 either = "1.8.1"
 env_logger = "0.11.3"
-futures = { version = "0.3.30", features = ["executor"] }
 http = "1.1.0"
 http-body = "1.0.0"
-indexmap = { version = "2.1.0", features = ["serde"] }
 indoc = "2.0.5"
-internal-baml-codegen = { path = "language_client_codegen" }
-internal-baml-core = { path = "baml-lib/baml-core" }
-internal-baml-jinja = { path = "baml-lib/jinja-runtime" }
-internal-llm-client = { path = "baml-lib/llm-client" }
-baml-lsp-types = { path = "baml-lsp-types" }
-jsonish = { path = "baml-lib/jsonish" }
 log = "0.4.20"
-# TODO: disable imports, etc
-minijinja = { version = "1.0.16", default-features = false, features = [
-  "macros",
-  "builtins",
-  "debug",
-  "preserve_order",
-  "adjacent_loop_items",
-  "unicode",
-  "json",
-  "unstable_machinery",
-  "unstable_machinery_serde",
-  "custom_syntax",
-  "internal_debug",
-  "deserialization",
-  # We don't want to use these features:
-  # multi_template
-  # loader
-  #
-] }
 once_cell = "1"
+pin-project-lite = "0.2.14"
 pretty_assertions = "1.4.1"
 rand = "0.8.5"
 regex = "1.10.4"
-reqwest = { version = "0.12.12", features = [
-  "json",
-  "native-tls-alpn",
-  "native-tls-vendored",
-  "stream",
-] }
 scopeguard = "1.2.0"
-secrecy = { version = "0.10.3", features = ["serde"] }
-serde_json = { version = "1", features = ["float_roundtrip", "preserve_order"] }
-serde = { version = "1", features = ["alloc", "derive", "rc"] }
 serde_yaml = "0.9.34"
 static_assertions = "1.1.0"
-strum = { version = "0.26.2", features = ["derive"] }
 strum_macros = "0.26.2"
 thiserror = "2.0.12"
-time = { version = "0.3.36", features = ["formatting"] }
-tracing-core = { version = "0.1.31" }
-pin-project-lite = "0.2.14"
 url = "2.5.2"
-uuid = { version = "1.8.0", features = ["v4", "v7", "serde"] }
 walkdir = "2.5.0"
 web-time = "1.1.0"
-tokio = { version = "1", default-features = false, features = [
-  "macros",
-  "time",
-] }
 
-[workspace.package]
-version = "0.88.0"
-authors = ["Boundary <contact@boundaryml.com>"]
+[workspace.dependencies.baml-cli]
+path = "cli"
 
-description = "BAML Toolchain"
-license-file = "LICENSE"
+[workspace.dependencies.baml-log]
+path = "baml-lib/baml-log"
 
-[workspace.metadata.workspaces]
-allow_branch = "canary"
+[workspace.dependencies.baml-lsp-types]
+path = "baml-lsp-types"
+
+[workspace.dependencies.baml-types]
+path = "baml-lib/baml-types"
+
+[workspace.dependencies.bstd]
+path = "bstd"
+
+[workspace.dependencies.clap]
+version = "4.4.6"
+features = [
+    "cargo",
+    "derive",
+]
+
+[workspace.dependencies.derive_more]
+version = "0.99.18"
+features = ["constructor"]
+
+[workspace.dependencies.futures]
+version = "0.3.30"
+features = ["executor"]
+
+[workspace.dependencies.indexmap]
+version = "2.1.0"
+features = ["serde"]
+
+[workspace.dependencies.internal-baml-codegen]
+path = "language_client_codegen"
+
+[workspace.dependencies.internal-baml-core]
+path = "baml-lib/baml-core"
+
+[workspace.dependencies.internal-baml-jinja]
+path = "baml-lib/jinja-runtime"
+
+[workspace.dependencies.internal-llm-client]
+path = "baml-lib/llm-client"
+
+[workspace.dependencies.jsonish]
+path = "baml-lib/jsonish"
+
+[workspace.dependencies.lsp-server]
+version = "0.7.6"
+
+[workspace.dependencies.lsp-types]
+version = "0.95.0"
+
+[workspace.dependencies.minijinja]
+version = "1.0.16"
+features = [
+    "macros",
+    "builtins",
+    "debug",
+    "preserve_order",
+    "adjacent_loop_items",
+    "unicode",
+    "json",
+    "unstable_machinery",
+    "unstable_machinery_serde",
+    "custom_syntax",
+    "internal_debug",
+    "deserialization",
+]
+default-features = false
+
+[workspace.dependencies.reqwest]
+version = "0.12.12"
+features = [
+    "json",
+    "native-tls-alpn",
+    "native-tls-vendored",
+    "stream",
+]
+
+[workspace.dependencies.secrecy]
+version = "0.10.3"
+features = ["serde"]
+
+[workspace.dependencies.serde]
+version = "1"
+features = [
+    "alloc",
+    "derive",
+    "rc",
+]
+
+[workspace.dependencies.serde_json]
+version = "1"
+features = [
+    "float_roundtrip",
+    "preserve_order",
+]
+
+[workspace.dependencies.strum]
+version = "0.26.2"
+features = ["derive"]
+
+[workspace.dependencies.time]
+version = "0.3.36"
+features = ["formatting"]
+
+[workspace.dependencies.tokio]
+version = "1"
+features = [
+    "macros",
+    "time",
+]
+default-features = false
+
+[workspace.dependencies.tracing-core]
+version = "0.1.31"
+
+[workspace.dependencies.uuid]
+version = "1.8.0"
+features = [
+    "v4",
+    "v7",
+    "serde",
+]
 
 [profile.dev]
 lto = false
diff --git a/engine/baml-lsp-types/Cargo.toml b/engine/baml-lsp-types/Cargo.toml
index dc820b13a4..ee2d1da0b1 100644
--- a/engine/baml-lsp-types/Cargo.toml
+++ b/engine/baml-lsp-types/Cargo.toml
@@ -21,7 +21,7 @@ internal-baml-codegen.workspace = true
 internal-baml-core.workspace = true
 jsonish = { path = "../baml-lib/jsonish" }
 internal-llm-client = { path = "../baml-lib/llm-client" }
-js-sys = "=0.3.69"
+js-sys = "=0.3.70"
 log.workspace = true
 serde.workspace = true
 serde_json.workspace = true
diff --git a/engine/baml-router/.gitignore b/engine/baml-router/.gitignore
new file mode 100644
index 0000000000..d27315f031
--- /dev/null
+++ b/engine/baml-router/.gitignore
@@ -0,0 +1,3 @@
+target
+node_modules
+.wrangler
diff --git a/engine/baml-router/Cargo.toml b/engine/baml-router/Cargo.toml
new file mode 100644
index 0000000000..5ced908a03
--- /dev/null
+++ b/engine/baml-router/Cargo.toml
@@ -0,0 +1,24 @@
+[package]
+name = "baml-router"
+version.workspace = true
+edition = "2021"
+authors.workspace = true
+
+[package.metadata.release]
+release = false
+
+# https://github.com/rustwasm/wasm-pack/issues/1247
+[package.metadata.wasm-pack.profile.release]
+wasm-opt = false
+
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+worker = { version="0.5.0", features=['http', 'axum'] }
+worker-macros = { version="0.5.0", features=['http'] }
+axum  = { version = "0.7", default-features = false, features = ["json"] }
+tower-service = "0.3.2"
+console_error_panic_hook = { version = "0.1.1" }
+serde.workspace = true
+serde_json.workspace = true
diff --git a/engine/baml-router/src/lib.rs b/engine/baml-router/src/lib.rs
new file mode 100644
index 0000000000..0bac9636b9
--- /dev/null
+++ b/engine/baml-router/src/lib.rs
@@ -0,0 +1,124 @@
+use axum::{routing::{get, post}, Router, Json, http::StatusCode};
+use serde::Deserialize;
+use tower_service::Service;
+use worker::*;
+
+fn router() -> Router {
+    Router::new()
+        .route("/", get(root))
+        .route("/v1/chat/completions/prompt", post(chat_completion_prompt))
+}
+
+#[event(fetch)]
+async fn fetch(
+    req: HttpRequest,
+    _env: Env,
+    _ctx: Context,
+) -> Result<axum::http::Response<axum::body::Body>> {
+    console_error_panic_hook::set_once();
+    Ok(router().call(req).await?)
+}
+
+pub async fn root() -> &'static str {
+    "Hello Axum!"
+}
+
+
+
+pub async fn chat_completion_prompt(
+    Json(mut body): Json<serde_json::Value>,
+) -> (StatusCode, Json<serde_json::Value>) {
+    if let Some(inner_body) = body.as_object_mut() {
+        let tools = inner_body.remove("tools").map(|v| serde_json::from_value::<Vec<OpenAITool>>(v.clone()).unwrap_or_default());
+        let tools = match tools {
+            Some(tools) => {
+                tools.into_iter().map(|tool| {
+                    match tool {
+                        // TODO(aaronvg): convert to type builder class
+                        OpenAITool::Function(function) => function,
+                    }
+                }).collect::<Vec<_>>()
+            },
+            None => return (StatusCode::BAD_REQUEST, Json(body)),
+        };
+
+        if let Some(messages) = inner_body.get_mut("messages") {
+            if let Some(messages) = messages.as_array_mut() {
+                messages.push(serde_json::json!({
+                    "role": "user",
+                    // TODO(aaronvg): call the actual method here.
+                    "content": "ctx.output_format"
+                }));
+            }
+        }
+    }
+
+    (StatusCode::OK, Json(body))
+}
+
+#[derive(Deserialize)]
+#[serde(tag = "type", content = "function", rename_all = "snake_case")]
+enum OpenAITool {
+    Function(OpenAIToolFunction),
+}
+
+#[derive(Deserialize)]
+struct OpenAIToolFunction {
+    name: String,
+    description: Option<String>,
+    parameters: Option<serde_json::Value>,
+    strict: Option<bool>,
+}
+
+#[cfg(test)]
+mod tests {
+    use serde_json::json;
+
+    use super::*;
+    
+    #[test]
+    fn test_openai_tool() {
+        let tool_str = r#"
+        [
+            {
+                "type": "function",
+                "function": {
+                    "name": "get_current_weather",
+                    "description": "Get the current weather in a given location",
+                    "parameters": {
+                        "type": "object",
+                        "properties": {
+                            "location": {
+                                "type": "string",
+                                "description": "The city and state, e.g. San Francisco, CA"
+                            },
+                            "unit": {"type": "string", "enum": ["celsius", "fahrenheit"]}
+                        },
+                        "required": ["location"]
+                    }
+                }   
+            }   
+        ]
+        "#;
+        let tool: Vec<OpenAITool> = serde_json::from_str(tool_str).unwrap();
+        assert_eq!(tool.len(), 1);
+        let tool = &tool[0];
+        let function = match tool {
+            OpenAITool::Function(function) => function,
+        };  
+        assert_eq!(function.name, "get_current_weather");
+        assert_eq!(function.description, Some("Get the current weather in a given location".to_string()));
+        assert_eq!(function.parameters.as_ref().unwrap(), &json!({
+            "type": "object",
+            "properties": {
+                "location": {
+                    "type": "string",
+                    "description": "The city and state, e.g. San Francisco, CA"
+                },
+                "unit": {"type": "string", "enum": ["celsius", "fahrenheit"]}
+            },
+            "required": ["location"]
+        }));
+    }
+    
+}
diff --git a/engine/baml-router/wrangler.toml b/engine/baml-router/wrangler.toml
new file mode 100644
index 0000000000..f95a37579d
--- /dev/null
+++ b/engine/baml-router/wrangler.toml
@@ -0,0 +1,6 @@
+name = "baml-router"
+main = "build/worker/shim.mjs"
+compatibility_date = "2025-05-21"
+
+[build]
+command = "cargo install -q worker-build && worker-build --release"
\ No newline at end of file
diff --git a/engine/baml-runtime/Cargo.toml b/engine/baml-runtime/Cargo.toml
index 32142e718e..1157fbae12 100644
--- a/engine/baml-runtime/Cargo.toml
+++ b/engine/baml-runtime/Cargo.toml
@@ -123,7 +123,7 @@ colored = { version = "2.1.0", default-features = false, features = [
   "no-color",
 ] }
 futures-timer = { version = "3.0.3", features = ["wasm-bindgen"] }
-js-sys = "=0.3.69"
+js-sys = "=0.3.70"
 reqwest = { version = "0.12.12", features = [
   "stream",
   "json",
diff --git a/engine/baml-schema-wasm/Cargo.toml b/engine/baml-schema-wasm/Cargo.toml
index 0ebc5adcc4..3891d9a21b 100644
--- a/engine/baml-schema-wasm/Cargo.toml
+++ b/engine/baml-schema-wasm/Cargo.toml
@@ -33,7 +33,7 @@ internal-baml-codegen.workspace = true
 internal-baml-core.workspace = true
 jsonish = { path = "../baml-lib/jsonish" }
 internal-llm-client = { path = "../baml-lib/llm-client" }
-js-sys = "=0.3.69"
+js-sys = "=0.3.70"
 log.workspace = true
 serde.workspace = true
 serde_json.workspace = true
@@ -42,7 +42,7 @@ time.workspace = true
 tokio = { workspace = true, features = ["sync"] }
 url.workspace = true
 uuid = { version = "1.8", features = ["v4", "js"] }
-wasm-bindgen = "=0.2.92"
+wasm-bindgen = "=0.2.93"
 wasm-bindgen-futures = "0.4.42"
 wasm-logger = { version = "0.2.0" }
 web-time.workspace = true