diff --git a/doc/psidk/src/development/services/rust-service/package.md b/doc/psidk/src/development/services/rust-service/package.md
index 14f2fe3f6..882d48cba 100644
--- a/doc/psidk/src/development/services/rust-service/package.md
+++ b/doc/psidk/src/development/services/rust-service/package.md
@@ -12,6 +12,7 @@ The available fields are:
 - `plugin`: May be present on any crate that builds a service. The value is a crate that should be built with `cargo component` and uploaded as `/plugin.wasm`
 - `flags`: [Flags](../../../specifications/data-formats/package.md#serviceservicejson) for the service.
 - `postinstall`: An array of actions to run when the package is installed. May be specified on the top-level crate or on any service. Actions from a single `postinstall` will be run in order. The order of actions from multiple crates is unspecified.
+- `data`: An array of `{src, dst}` paths to upload to the service. `src` is relative to the location of Cargo.toml. If `src` is a directory, its contents will be included recursively.
 - `dependencies`: Additional packages, not build by cargo, that the package depends on.
 
 Example:
@@ -32,6 +33,8 @@ server = "example"
 plugin = "example-plugin"
 # Run the service's init action
 postinstall = [{sender="tpack", service="tpack", method="init", rawData="0000"}]
+# Upload the UI
+data = [{src = "ui/", dst = "/"}]
 
 [package.metadata.psibase.dependencies]
 HttpServer = "0.12.0"
diff --git a/rust/cargo-psibase/src/package.rs b/rust/cargo-psibase/src/package.rs
index 1ec19267c..cdc82a29f 100644
--- a/rust/cargo-psibase/src/package.rs
+++ b/rust/cargo-psibase/src/package.rs
@@ -14,6 +14,12 @@ use std::io::{BufReader, Seek, Write};
 use std::path::{Path, PathBuf};
 use zip::write::{FileOptions, ZipWriter};
 
+#[derive(Serialize, Deserialize, Default)]
+struct DataFiles {
+    src: String,
+    dst: String,
+}
+
 #[derive(Serialize, Deserialize, Default)]
 #[serde(default)]
 pub struct PsibaseMetadata {
@@ -25,6 +31,7 @@ pub struct PsibaseMetadata {
     dependencies: HashMap<String, String>,
     services: Option<Vec<String>>,
     postinstall: Option<Vec<Action>>,
+    data: Vec<DataFiles>,
 }
 
 impl PsibaseMetadata {
@@ -104,7 +111,7 @@ fn should_build_package(
     filename: &Path,
     meta: &Meta,
     services: &[(&String, ServiceInfo, PathBuf)],
-    data: &[(&String, &str, PathBuf)],
+    data: &[(&String, String, PathBuf)],
     postinstall: &[Action],
 ) -> Result<bool, anyhow::Error> {
     let timestamp = if let Ok(metadata) = filename.metadata() {
@@ -148,7 +155,7 @@ fn should_build_package(
             return Ok(true);
         }
         let account: AccountNumber = service.parse()?;
-        new_data.push((account.value, *dest));
+        new_data.push((account.value, dest.as_str()));
     }
     existing_data.sort();
     new_data.sort();
@@ -164,6 +171,35 @@ fn should_build_package(
     Ok(false)
 }
 
+fn add_files<'a>(
+    service: &'a String,
+    src: &Path,
+    dest: &String,
+    out: &mut Vec<(&'a String, String, PathBuf)>,
+) -> Result<(), anyhow::Error> {
+    if src.is_file() {
+        out.push((service, dest.clone(), src.to_path_buf()));
+    } else if src.is_dir() {
+        for entry in src.read_dir()? {
+            let entry = entry?;
+            add_files(
+                service,
+                &entry.path(),
+                &(dest.clone()
+                    + "/"
+                    + entry.file_name().to_str().ok_or_else(|| {
+                        anyhow!(
+                            "non-unicode file name: {}",
+                            entry.file_name().to_string_lossy()
+                        )
+                    })?),
+                out,
+            )?;
+        }
+    }
+    Ok(())
+}
+
 pub async fn build_package(
     args: &Args,
     metadata: &MetadataIndex<'_>,
@@ -257,6 +293,17 @@ pub async fn build_package(
                 };
                 plugins.push((plugin, &package.name, "/plugin.wasm", &id.repr));
             }
+            for data in &pmeta.data {
+                let src = package.manifest_path.parent().unwrap().join(&data.src);
+                let mut dest = data.dst.clone();
+                if !dest.starts_with('/') {
+                    dest = "/".to_string() + &dest;
+                }
+                if dest.ends_with('/') {
+                    dest.pop();
+                }
+                add_files(&package.name, src.as_std_path(), &dest, &mut data_files)?;
+            }
             services.push((&package.name, info, &package.id.repr));
             if let Some(actions) = &pmeta.postinstall {
                 postinstall.extend_from_slice(actions.as_slice());
@@ -313,7 +360,7 @@ pub async fn build_package(
                 plugin
             ))?
         };
-        data_files.push((service, path, paths.pop().unwrap()))
+        data_files.push((service, path.to_string(), paths.pop().unwrap()))
     }
 
     let out_dir = get_package_dir(args, metadata);
diff --git a/rust/test_package/query/Cargo.toml b/rust/test_package/query/Cargo.toml
index db6df3a13..7822a2cfe 100644
--- a/rust/test_package/query/Cargo.toml
+++ b/rust/test_package/query/Cargo.toml
@@ -10,6 +10,7 @@ publish = false
 
 [package.metadata.psibase]
 plugin = "tpack-plugin"
+data = [{src = "../ui", dst = "/"}]
 
 [dependencies]
 psibase = { path = "../../psibase", version = "0.12.0" }
diff --git a/rust/test_package/ui/index.html b/rust/test_package/ui/index.html
new file mode 100644
index 000000000..350147c29
--- /dev/null
+++ b/rust/test_package/ui/index.html
@@ -0,0 +1,5 @@
+<html>
+  <body>
+    Lorem ipsum dolor sit amet
+  </body>
+</html>