source_name should be provided in V10, accessor_names inside

Error message

source_name should be provided in V10, accessor_names inside module

What it means

In schema-def validation for V10+, `RawIndexDefV10.source_name` is an Option, but the v10 format requires it, so `validate_index_def_v10` unwraps with this expect. The field is populated by the spacetimedb macro codegen; hitting the panic means the RawIndexDefV10 was hand-constructed without source_name, or produced by mismatched macro/schema crate versions.

Source

Thrown at crates/schema/src/def/validate/v9.rs:1234

            namespace: NamespacePath::root(),
            name: name.clone(),
            accessor_name: codegen_name,
            source_name: name,
            algorithm,
        })
    }

    /// Validates an index definition for V10 and later versions
    pub(crate) fn validate_index_def_v10(&mut self, index: RawIndexDefV10) -> Result<IndexDef> {
        let RawIndexDefV10 {
            source_name,
            algorithm: algorithm_raw,
            accessor_name,
        } = index;

        //source_name will be used as alias, hence we need to add it to the global namespace as
        //well.
        let source_name = source_name.expect("source_name should be provided in V10, accessor_names inside module");
        let source_name = self.add_to_global_namespace(source_name.clone())?;

        let name = if self.module_validator.explicit_names.indexes.get(&source_name).is_some() {
            self.module_validator.resolve_index_ident(source_name.clone())?
        } else {
            identifier(generate_index_name(
                &self.table_ident,
                self.product_type,
                &algorithm_raw,
            ))?
        };

        let name = if *name.as_raw() != source_name {
            self.add_to_global_namespace(name.as_raw().clone())?
        } else {
            name.as_raw().clone()
        };

View on GitHub (pinned to 524b4487d9)

Solutions

Set source_name (Some(identifier)) when constructing RawIndexDefV10 manually — it becomes the index's alias in the global namespace.
Align spacetimedb crate versions so macro codegen and schema validator agree (check cargo tree for mixed versions).
Prefer deriving index defs via #[spacetimedb::table(index(...))] instead of hand-building raw defs.

Example fix

// before
let def = RawIndexDefV10 { source_name: None, algorithm, accessor_name };

// after: V10 defs require the source name
let def = RawIndexDefV10 { source_name: Some(identifier("players_name_idx")?), algorithm, accessor_name };

Defensive patterns

Strategy: validation

Validate before calling

let def = RawIndexDefV10 { source_name: Some(index_name.clone()), algorithm, accessor_name };
assert!(def.source_name.is_some(), "V10 index defs require source_name");

Prevention

Pin consistent versions of all spacetimedb crates in the workspace.
Let macros generate index defs; don't hand-assemble raw def structs.
Add a smoke test validating a generated module def after dependency upgrades.

When it happens

Trigger: Manually building `RawIndexDefV10 { source_name: None, .. }` and validating it; or mixing an older bindings-macro crate that emits V10 defs without source_name with a newer schema crate that requires it.

Common situations: Custom build pipelines that synthesize index defs; dependency version skew among spacetimedb crates (Cargo tree -p spacetimedb-bindings-macro / spacetimedb-schema); forked codegen missing the field.

Related errors

AI-assisted analysis of clockworklabs/SpacetimeDB@524b4487d9 (2026-08-16). Data as JSON: /api/errors/359f930b8a292d66. Report an issue: GitHub.