diff --git a/.changeset/chatty-clocks-relax.md b/.changeset/chatty-clocks-relax.md
new file mode 100644
index 000000000..d6edb7d11
--- /dev/null
+++ b/.changeset/chatty-clocks-relax.md
@@ -0,0 +1,5 @@
+---
+'@openfn/ws-worker': patch
+---
+
+Allow steps to specify their own adaptor version
diff --git a/packages/ws-worker/src/util/convert-lightning-plan.ts b/packages/ws-worker/src/util/convert-lightning-plan.ts
index 45a5e52e7..39629935e 100644
--- a/packages/ws-worker/src/util/convert-lightning-plan.ts
+++ b/packages/ws-worker/src/util/convert-lightning-plan.ts
@@ -88,8 +88,16 @@ export default (
       const job = step as Job;
       if (job.expression?.match(/(collections\.)/)) {
         hasCollections = true;
-        job.adaptors ??= [];
-        job.adaptors.push(`@openfn/language-collections@${collectionsVersion}`);
+        if (
+          !job.adaptors?.find((v) =>
+            v.startsWith('@openfn/language-collections')
+          )
+        ) {
+          job.adaptors ??= [];
+          job.adaptors.push(
+            `@openfn/language-collections@${collectionsVersion}`
+          );
+        }
       }
     });
     return hasCollections;
diff --git a/packages/ws-worker/test/util/convert-lightning-plan.test.ts b/packages/ws-worker/test/util/convert-lightning-plan.test.ts
index ed8f9da31..e193a7273 100644
--- a/packages/ws-worker/test/util/convert-lightning-plan.test.ts
+++ b/packages/ws-worker/test/util/convert-lightning-plan.test.ts
@@ -614,7 +614,36 @@ test('append the collections adaptor to jobs that use it', (t) => {
   t.deepEqual(b.adaptors, ['common', '@openfn/language-collections@1.0.0']);
 });
 
-test('append the collections credential to jobs that use it', (t) => {
+test('do not append the collections adaptor to jobs that already have it', (t) => {
+  const run: Partial<LightningPlan> = {
+    id: 'w',
+    jobs: [
+      createNode({
+        id: 'a',
+        body: 'collections.each("c", "k", (state) => state)',
+        adaptor: '@openfn/language-collections@latest',
+      }),
+    ],
+    triggers: [{ id: 't', type: 'cron' }],
+    edges: [createEdge('t', 'a')],
+  };
+
+  const { plan } = convertPlan(run as LightningPlan, {
+    collectionsVersion: '1.0.0',
+  });
+
+  const [_t, a] = plan.workflow.steps;
+
+  // @ts-ignore
+  t.deepEqual(a.adaptors, ['@openfn/language-collections@latest']);
+
+  t.deepEqual(plan.workflow.credentials, {
+    collections_token: true,
+    collections_endpoint: true,
+  });
+});
+
+test('append the collections credential to workflows that use it', (t) => {
   const run: Partial<LightningPlan> = {
     id: 'w',
     jobs: [