diff --git a/packages/electric-db-collection/tests/electric-recovery-oracle.test.ts b/packages/electric-db-collection/tests/electric-recovery-oracle.test.ts
index 3466af5f4f..cfeef06173 100644
--- a/packages/electric-db-collection/tests/electric-recovery-oracle.test.ts
+++ b/packages/electric-db-collection/tests/electric-recovery-oracle.test.ts
@@ -161,7 +161,7 @@ function change(
   operation: `insert` | `update` | `delete`,
   value: Partial<Item>,
 ): Message<Item> {
-  return { key: String(value.id), value: value, headers: { operation } }
+  return { key: String(value.id), value: value as Item, headers: { operation } }
 }
 
 function fixture(
@@ -307,7 +307,7 @@ function fixture(
         $collectionId: _collectionId,
         ...value
       } = row
-      return structuredClone(value)
+      return structuredClone(value) as Item
     }).sort((a, b) => a.id - b.id)
   const durableRows = () =>
     structuredClone([...rows.values()].sort((a, b) => a.id - b.id))
diff --git a/packages/query-db-collection/src/query.ts b/packages/query-db-collection/src/query.ts
index 16bbe5015f..6d18791410 100644
--- a/packages/query-db-collection/src/query.ts
+++ b/packages/query-db-collection/src/query.ts
@@ -803,6 +803,7 @@ export function queryCollectionOptions(
 
   // Validate required parameters
 
+  // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
   if (!queryKey) {
     throw new QueryKeyRequiredError()
   }
@@ -812,6 +813,7 @@ export function queryCollectionOptions(
     throw new QueryFnRequiredError()
   }
 
+  // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
   if (!queryClient) {
     throw new QueryClientRequiredError()
   }
diff --git a/packages/query-db-collection/tests/query.test.ts b/packages/query-db-collection/tests/query.test.ts
index 3361d2ddba..1dbd38b2df 100644
--- a/packages/query-db-collection/tests/query.test.ts
+++ b/packages/query-db-collection/tests/query.test.ts
@@ -3652,7 +3652,7 @@ describe(`QueryCollection`, () => {
 
         // A Query Core `removed` event can arrive before this collection's observer
         // is detached. Existing semantics retain the active rows and observer.
-        queryClient.getQueryCache().remove(subsetQuery)
+        queryClient.getQueryCache().remove(subsetQuery!)
         expect(queryClient.getQueryCache().findAll({ queryKey })).toHaveLength(
           0,
         )
diff --git a/packages/trailbase-db-collection/src/trailbase.ts b/packages/trailbase-db-collection/src/trailbase.ts
index 53ea350800..193bb71d89 100644
--- a/packages/trailbase-db-collection/src/trailbase.ts
+++ b/packages/trailbase-db-collection/src/trailbase.ts
@@ -264,7 +264,7 @@ export function trailBaseCollectionOptions<
           for (let i = 0; i < Math.min(length, remaining); ++i) {
             write({
               type: `insert`,
-              value: parse(response.records[i]),
+              value: parse(response.records[i]!),
             })
           }
 
@@ -287,7 +287,7 @@ export function trailBaseCollectionOptions<
               (opts.subscription === undefined || lastKey !== undefined)
             ) {
               cursors.set(
-                getKey(parse(response.records.at(-1))),
+                getKey(parse(response.records.at(-1)!)),
                 response.cursor,
               )
             }