diff --git a/crates/sparrow-execution/src/lib.rs b/crates/sparrow-execution/src/lib.rs
index 1c1ac8c63..2800b7afb 100644
--- a/crates/sparrow-execution/src/lib.rs
+++ b/crates/sparrow-execution/src/lib.rs
@@ -13,7 +13,8 @@
 use arrow_array::RecordBatch;
 use arrow_schema::{DataType, Field, Schema, SchemaRef, TimeUnit};
 use hashbrown::HashMap;
-use sparrow_interfaces::{ExecutionOptions, Source};
+use sparrow_interfaces::source::Source;
+use sparrow_interfaces::ExecutionOptions;
 use sparrow_physical::StepId;
 use sparrow_transforms::TransformPipeline;
 use std::sync::Arc;
diff --git a/crates/sparrow-execution/src/source_tasks.rs b/crates/sparrow-execution/src/source_tasks.rs
index 1bc8fdb87..2f6aa0d18 100644
--- a/crates/sparrow-execution/src/source_tasks.rs
+++ b/crates/sparrow-execution/src/source_tasks.rs
@@ -2,7 +2,7 @@ use error_stack::ResultExt;
 use futures::stream::{BoxStream, FuturesUnordered};
 use futures::{StreamExt, TryStreamExt};
 use sparrow_batch::Batch;
-use sparrow_interfaces::SourceError;
+use sparrow_interfaces::source::SourceError;
 use sparrow_scheduler::{Injector, InputHandles};
 use tracing::Instrument;
 use uuid::Uuid;
diff --git a/crates/sparrow-execution/src/tests.rs b/crates/sparrow-execution/src/tests.rs
index 853c58e32..81763ddba 100644
--- a/crates/sparrow-execution/src/tests.rs
+++ b/crates/sparrow-execution/src/tests.rs
@@ -1,6 +1,6 @@
 use arrow_array::cast::AsArray;
 use arrow_array::{Int64Array, RecordBatch, TimestampNanosecondArray, UInt64Array};
-use sparrow_interfaces::{Source, SourceExt};
+use sparrow_interfaces::source::{Source, SourceExt};
 use sparrow_logical::ExprRef;
 use sparrow_session::partitioned::Session;
 use sparrow_sources::InMemory;
diff --git a/crates/sparrow-interfaces/src/lib.rs b/crates/sparrow-interfaces/src/lib.rs
index a2afbd79f..02e4eb741 100644
--- a/crates/sparrow-interfaces/src/lib.rs
+++ b/crates/sparrow-interfaces/src/lib.rs
@@ -8,9 +8,6 @@
 )]
 
 mod execution_options;
-mod source;
-mod source_error;
+pub mod source;
 
 pub use execution_options::*;
-pub use source::*;
-pub use source_error::SourceError;
diff --git a/crates/sparrow-interfaces/src/source.rs b/crates/sparrow-interfaces/src/source.rs
index bbb3a2bb1..5df71cbe7 100644
--- a/crates/sparrow-interfaces/src/source.rs
+++ b/crates/sparrow-interfaces/src/source.rs
@@ -4,7 +4,7 @@ use arrow_schema::{DataType, SchemaRef};
 use futures::stream::BoxStream;
 use sparrow_batch::Batch;
 
-use crate::{ExecutionOptions, SourceError};
+use crate::ExecutionOptions;
 
 /// Trait implemented by sources.
 pub trait Source: Send + Sync {
@@ -30,6 +30,29 @@ pub trait Source: Send + Sync {
     fn as_any(&self) -> &dyn std::any::Any;
 }
 
+#[non_exhaustive]
+#[derive(derive_more::Display, Debug)]
+pub enum SourceError {
+    #[display(fmt = "internal error: {}", _0)]
+    Internal(&'static str),
+    #[display(fmt = "failed to add in-memory batch")]
+    Add,
+    #[display(fmt = "receiver lagged")]
+    ReceiverLagged,
+}
+
+impl error_stack::Context for SourceError {}
+
+impl SourceError {
+    pub fn internal() -> Self {
+        SourceError::Internal("no additional context")
+    }
+
+    pub fn internal_msg(msg: &'static str) -> Self {
+        SourceError::Internal(msg)
+    }
+}
+
 pub trait SourceExt {
     fn downcast_source_opt<T: Source + 'static>(&self) -> Option<&T>;
     fn downcast_source<T: Source + 'static>(&self) -> &T {
diff --git a/crates/sparrow-interfaces/src/source_error.rs b/crates/sparrow-interfaces/src/source_error.rs
deleted file mode 100644
index 815087a6f..000000000
--- a/crates/sparrow-interfaces/src/source_error.rs
+++ /dev/null
@@ -1,22 +0,0 @@
-#[non_exhaustive]
-#[derive(derive_more::Display, Debug)]
-pub enum SourceError {
-    #[display(fmt = "internal error: {}", _0)]
-    Internal(&'static str),
-    #[display(fmt = "failed to add in-memory batch")]
-    Add,
-    #[display(fmt = "receiver lagged")]
-    ReceiverLagged,
-}
-
-impl error_stack::Context for SourceError {}
-
-impl SourceError {
-    pub fn internal() -> Self {
-        SourceError::Internal("no additional context")
-    }
-
-    pub fn internal_msg(msg: &'static str) -> Self {
-        SourceError::Internal(msg)
-    }
-}
diff --git a/crates/sparrow-session/src/partitioned/session.rs b/crates/sparrow-session/src/partitioned/session.rs
index ee77f44e4..129f4de82 100644
--- a/crates/sparrow-session/src/partitioned/session.rs
+++ b/crates/sparrow-session/src/partitioned/session.rs
@@ -5,7 +5,8 @@ use error_stack::ResultExt;
 use futures::FutureExt;
 use hashbrown::HashMap;
 use sparrow_compiler::NearestMatches;
-use sparrow_interfaces::{ExecutionOptions, Source};
+use sparrow_interfaces::source::Source;
+use sparrow_interfaces::ExecutionOptions;
 use sparrow_logical::{ExprRef, Literal};
 use uuid::Uuid;
 
diff --git a/crates/sparrow-sources/src/in_memory.rs b/crates/sparrow-sources/src/in_memory.rs
index 6c6d40d14..e37cd6106 100644
--- a/crates/sparrow-sources/src/in_memory.rs
+++ b/crates/sparrow-sources/src/in_memory.rs
@@ -6,11 +6,10 @@ use error_stack::{IntoReportCompat, ResultExt};
 use futures::{Stream, StreamExt, TryStreamExt};
 
 use sparrow_batch::Batch;
-use sparrow_interfaces::{ExecutionOptions, Source};
+use sparrow_interfaces::source::{Source, SourceError};
+use sparrow_interfaces::ExecutionOptions;
 use sparrow_merge::old::homogeneous_merge;
 
-use sparrow_interfaces::SourceError;
-
 /// A shared, synchronized container for in-memory batches.
 pub struct InMemory {
     /// The prepared schema.