diff --git a/oxide-api/src/Api.ts b/oxide-api/src/Api.ts
index 19b085e..0f3d77a 100644
--- a/oxide-api/src/Api.ts
+++ b/oxide-api/src/Api.ts
@@ -5174,6 +5174,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5235,6 +5239,13 @@ export class Api extends HttpClient {
         path: `/v1/certificates`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -5249,6 +5260,10 @@ export class Api extends HttpClient {
         path: `/v1/certificates`,
         method: "POST",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5262,6 +5277,10 @@ export class Api extends HttpClient {
       return this.request<Certificate>({
         path: `/v1/certificates/${path.certificate}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5289,6 +5308,13 @@ export class Api extends HttpClient {
         path: `/v1/disks`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -5304,6 +5330,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5321,6 +5351,10 @@ export class Api extends HttpClient {
         path: `/v1/disks/${path.disk}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5444,6 +5478,12 @@ export class Api extends HttpClient {
         path: `/v1/disks/${path.disk}/metrics/${path.metric}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.timestamp = new Date(o.timestamp);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -5458,6 +5498,13 @@ export class Api extends HttpClient {
         path: `/v1/floating-ips`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -5476,6 +5523,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5493,6 +5544,10 @@ export class Api extends HttpClient {
         path: `/v1/floating-ips/${path.floatingIp}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5516,6 +5571,10 @@ export class Api extends HttpClient {
         method: "PUT",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5559,6 +5618,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5579,6 +5642,10 @@ export class Api extends HttpClient {
         path: `/v1/floating-ips/${path.floatingIp}/detach`,
         method: "POST",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5620,6 +5687,13 @@ export class Api extends HttpClient {
         path: `/v1/images`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -5638,6 +5712,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5655,6 +5733,10 @@ export class Api extends HttpClient {
         path: `/v1/images/${path.image}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5689,6 +5771,10 @@ export class Api extends HttpClient {
         path: `/v1/images/${path.image}/demote`,
         method: "POST",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5706,6 +5792,10 @@ export class Api extends HttpClient {
         path: `/v1/images/${path.image}/promote`,
         method: "POST",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5720,6 +5810,14 @@ export class Api extends HttpClient {
         path: `/v1/instances`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            o.time_run_state_updated = new Date(o.time_run_state_updated);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -5738,6 +5836,11 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+          o.time_run_state_updated = new Date(o.time_run_state_updated);
+        },
         ...params,
       });
     },
@@ -5755,6 +5858,11 @@ export class Api extends HttpClient {
         path: `/v1/instances/${path.instance}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+          o.time_run_state_updated = new Date(o.time_run_state_updated);
+        },
         ...params,
       });
     },
@@ -5792,6 +5900,13 @@ export class Api extends HttpClient {
         path: `/v1/instances/${path.instance}/disks`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -5815,6 +5930,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5838,6 +5957,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -5918,6 +6041,11 @@ export class Api extends HttpClient {
         path: `/v1/instances/${path.instance}/reboot`,
         method: "POST",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+          o.time_run_state_updated = new Date(o.time_run_state_updated);
+        },
         ...params,
       });
     },
@@ -5958,6 +6086,13 @@ export class Api extends HttpClient {
         path: `/v1/instances/${path.instance}/ssh-public-keys`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -5975,6 +6110,11 @@ export class Api extends HttpClient {
         path: `/v1/instances/${path.instance}/start`,
         method: "POST",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+          o.time_run_state_updated = new Date(o.time_run_state_updated);
+        },
         ...params,
       });
     },
@@ -5992,6 +6132,11 @@ export class Api extends HttpClient {
         path: `/v1/instances/${path.instance}/stop`,
         method: "POST",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+          o.time_run_state_updated = new Date(o.time_run_state_updated);
+        },
         ...params,
       });
     },
@@ -6006,6 +6151,13 @@ export class Api extends HttpClient {
         path: `/v1/ip-pools`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6019,6 +6171,10 @@ export class Api extends HttpClient {
       return this.request<SiloIpPool>({
         path: `/v1/ip-pools/${path.pool}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6084,6 +6240,13 @@ export class Api extends HttpClient {
         path: `/v1/me/ssh-keys`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6098,6 +6261,10 @@ export class Api extends HttpClient {
         path: `/v1/me/ssh-keys`,
         method: "POST",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6111,6 +6278,10 @@ export class Api extends HttpClient {
       return this.request<SshKey>({
         path: `/v1/me/ssh-keys/${path.sshKey}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6141,6 +6312,12 @@ export class Api extends HttpClient {
         path: `/v1/metrics/${path.metricName}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.timestamp = new Date(o.timestamp);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6155,6 +6332,13 @@ export class Api extends HttpClient {
         path: `/v1/network-interfaces`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6176,6 +6360,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6196,6 +6384,10 @@ export class Api extends HttpClient {
         path: `/v1/network-interfaces/${path.interface}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6219,6 +6411,10 @@ export class Api extends HttpClient {
         method: "PUT",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6287,6 +6483,13 @@ export class Api extends HttpClient {
         path: `/v1/projects`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6301,6 +6504,10 @@ export class Api extends HttpClient {
         path: `/v1/projects`,
         method: "POST",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6314,6 +6521,10 @@ export class Api extends HttpClient {
       return this.request<Project>({
         path: `/v1/projects/${path.project}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6328,6 +6539,10 @@ export class Api extends HttpClient {
         path: `/v1/projects/${path.project}`,
         method: "PUT",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6385,6 +6600,13 @@ export class Api extends HttpClient {
         path: `/v1/snapshots`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6403,6 +6625,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6420,6 +6646,10 @@ export class Api extends HttpClient {
         path: `/v1/snapshots/${path.snapshot}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6451,6 +6681,13 @@ export class Api extends HttpClient {
         path: `/v1/system/hardware/disks`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6464,6 +6701,10 @@ export class Api extends HttpClient {
       return this.request<PhysicalDisk>({
         path: `/v1/system/hardware/disks/${path.diskId}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6478,6 +6719,13 @@ export class Api extends HttpClient {
         path: `/v1/system/hardware/racks`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6491,6 +6739,10 @@ export class Api extends HttpClient {
       return this.request<Rack>({
         path: `/v1/system/hardware/racks/${path.rackId}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6505,6 +6757,13 @@ export class Api extends HttpClient {
         path: `/v1/system/hardware/sleds`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6532,6 +6791,10 @@ export class Api extends HttpClient {
       return this.request<Sled>({
         path: `/v1/system/hardware/sleds/${path.sledId}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6552,6 +6815,13 @@ export class Api extends HttpClient {
         path: `/v1/system/hardware/sleds/${path.sledId}/disks`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6572,6 +6842,13 @@ export class Api extends HttpClient {
         path: `/v1/system/hardware/sleds/${path.sledId}/instances`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6697,6 +6974,13 @@ export class Api extends HttpClient {
         path: `/v1/system/hardware/switches`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6710,6 +6994,10 @@ export class Api extends HttpClient {
       return this.request<Switch>({
         path: `/v1/system/hardware/switches/${path.switchId}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6724,6 +7012,13 @@ export class Api extends HttpClient {
         path: `/v1/system/identity-providers`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6806,6 +7101,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6826,6 +7125,10 @@ export class Api extends HttpClient {
         path: `/v1/system/identity-providers/saml/${path.provider}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6840,6 +7143,13 @@ export class Api extends HttpClient {
         path: `/v1/system/ip-pools`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6854,6 +7164,10 @@ export class Api extends HttpClient {
         path: `/v1/system/ip-pools`,
         method: "POST",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6867,6 +7181,10 @@ export class Api extends HttpClient {
       return this.request<IpPool>({
         path: `/v1/system/ip-pools/${path.pool}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6881,6 +7199,10 @@ export class Api extends HttpClient {
         path: `/v1/system/ip-pools/${path.pool}`,
         method: "PUT",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -6914,6 +7236,12 @@ export class Api extends HttpClient {
         path: `/v1/system/ip-pools/${path.pool}/ranges`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -6928,6 +7256,9 @@ export class Api extends HttpClient {
         path: `/v1/system/ip-pools/${path.pool}/ranges/add`,
         method: "POST",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+        },
         ...params,
       });
     },
@@ -7026,6 +7357,10 @@ export class Api extends HttpClient {
       return this.request<IpPool>({
         path: `/v1/system/ip-pools-service`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7040,6 +7375,12 @@ export class Api extends HttpClient {
         path: `/v1/system/ip-pools-service/ranges`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7054,6 +7395,9 @@ export class Api extends HttpClient {
         path: `/v1/system/ip-pools-service/ranges/add`,
         method: "POST",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+        },
         ...params,
       });
     },
@@ -7085,6 +7429,12 @@ export class Api extends HttpClient {
         path: `/v1/system/metrics/${path.metricName}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.timestamp = new Date(o.timestamp);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7099,6 +7449,13 @@ export class Api extends HttpClient {
         path: `/v1/system/networking/address-lot`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7156,6 +7513,10 @@ export class Api extends HttpClient {
       return this.request<AllowList>({
         path: `/v1/system/networking/allow-list`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7170,6 +7531,10 @@ export class Api extends HttpClient {
         path: `/v1/system/networking/allow-list`,
         method: "PUT",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7222,6 +7587,13 @@ export class Api extends HttpClient {
         path: `/v1/system/networking/bgp`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7236,6 +7608,10 @@ export class Api extends HttpClient {
         path: `/v1/system/networking/bgp`,
         method: "POST",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7278,6 +7654,10 @@ export class Api extends HttpClient {
         path: `/v1/system/networking/bgp-announce-set`,
         method: "PUT",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7407,6 +7787,13 @@ export class Api extends HttpClient {
         path: `/v1/system/networking/switch-port-settings`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7527,6 +7914,13 @@ export class Api extends HttpClient {
         path: `/v1/system/silos`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7538,6 +7932,10 @@ export class Api extends HttpClient {
         path: `/v1/system/silos`,
         method: "POST",
         body,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7551,6 +7949,10 @@ export class Api extends HttpClient {
       return this.request<Silo>({
         path: `/v1/system/silos/${path.silo}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7581,6 +7983,13 @@ export class Api extends HttpClient {
         path: `/v1/system/silos/${path.silo}/ip-pools`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7686,6 +8095,13 @@ export class Api extends HttpClient {
         path: `/v1/system/users-builtin`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7699,6 +8115,10 @@ export class Api extends HttpClient {
       return this.request<UserBuiltin>({
         path: `/v1/system/users-builtin/${path.user}`,
         method: "GET",
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7754,6 +8174,12 @@ export class Api extends HttpClient {
         path: `/v1/timeseries/schema`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.created = new Date(o.created);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7792,6 +8218,13 @@ export class Api extends HttpClient {
         path: `/v1/vpc-firewall-rules`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.rules = o.rules.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7813,6 +8246,13 @@ export class Api extends HttpClient {
         method: "PUT",
         body,
         query,
+        transformResponse: (o) => {
+          o.rules = o.rules.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7827,6 +8267,13 @@ export class Api extends HttpClient {
         path: `/v1/vpc-router-routes`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7845,6 +8292,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7865,6 +8316,10 @@ export class Api extends HttpClient {
         path: `/v1/vpc-router-routes/${path.route}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7888,6 +8343,10 @@ export class Api extends HttpClient {
         method: "PUT",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7922,6 +8381,13 @@ export class Api extends HttpClient {
         path: `/v1/vpc-routers`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -7940,6 +8406,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7957,6 +8427,10 @@ export class Api extends HttpClient {
         path: `/v1/vpc-routers/${path.router}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -7980,6 +8454,10 @@ export class Api extends HttpClient {
         method: "PUT",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -8014,6 +8492,13 @@ export class Api extends HttpClient {
         path: `/v1/vpc-subnets`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -8032,6 +8517,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -8049,6 +8538,10 @@ export class Api extends HttpClient {
         path: `/v1/vpc-subnets/${path.subnet}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -8072,6 +8565,10 @@ export class Api extends HttpClient {
         method: "PUT",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -8112,6 +8609,13 @@ export class Api extends HttpClient {
         path: `/v1/vpc-subnets/${path.subnet}/network-interfaces`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -8126,6 +8630,13 @@ export class Api extends HttpClient {
         path: `/v1/vpcs`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.items = o.items.map((o: any) => {
+            o.time_created = new Date(o.time_created);
+            o.time_modified = new Date(o.time_modified);
+            return o;
+          });
+        },
         ...params,
       });
     },
@@ -8141,6 +8652,10 @@ export class Api extends HttpClient {
         method: "POST",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -8158,6 +8673,10 @@ export class Api extends HttpClient {
         path: `/v1/vpcs/${path.vpc}`,
         method: "GET",
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
@@ -8181,6 +8700,10 @@ export class Api extends HttpClient {
         method: "PUT",
         body,
         query,
+        transformResponse: (o) => {
+          o.time_created = new Date(o.time_created);
+          o.time_modified = new Date(o.time_modified);
+        },
         ...params,
       });
     },
diff --git a/oxide-api/src/http-client.ts b/oxide-api/src/http-client.ts
index b820c3b..00d8c2b 100644
--- a/oxide-api/src/http-client.ts
+++ b/oxide-api/src/http-client.ts
@@ -6,7 +6,7 @@
  * Copyright Oxide Computer Company
  */
 
-import { camelToSnake, processResponseBody, snakeify, isNotNull } from "./util";
+import { camelToSnake, snakeifyKeys, isNotNull, camelifyKeys } from "./util";
 
 /** Success responses from the API */
 export type ApiSuccess<Data> = {
@@ -62,6 +62,8 @@ function encodeQueryParam(key: string, value: unknown) {
 
 export async function handleResponse<Data>(
   response: Response,
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  transformResponse?: (o: any) => void,
 ): Promise<ApiResult<Data>> {
   const respText = await response.text();
 
@@ -70,8 +72,13 @@ export async function handleResponse<Data>(
   try {
     // don't bother trying to parse empty responses like 204s
     // TODO: is empty object what we want here?
-    respJson =
-      respText.length > 0 ? processResponseBody(JSON.parse(respText)) : {};
+    if (respText.length > 0) {
+      respJson = JSON.parse(respText);
+      transformResponse?.(respJson); // no assignment because this mutates the object
+      respJson = camelifyKeys(respJson);
+    } else {
+      respJson = {};
+    }
   } catch (e) {
     return {
       type: "client_error",
@@ -115,6 +122,8 @@ export interface FullParams extends FetchParams {
   body?: unknown;
   host?: string;
   method?: string;
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  transformResponse?: (o: any) => void;
 }
 
 export interface ApiConfig {
@@ -148,14 +157,15 @@ export class HttpClient {
     path,
     query,
     host,
+    transformResponse,
     ...fetchParams
   }: FullParams): Promise<ApiResult<Data>> {
     const url = (host || this.host) + path + toQueryString(query);
     const init = {
       ...mergeParams(this.baseParams, fetchParams),
-      body: JSON.stringify(snakeify(body), replacer),
+      body: JSON.stringify(snakeifyKeys(body), replacer),
     };
-    return handleResponse(await fetch(url, init));
+    return handleResponse(await fetch(url, init), transformResponse);
   }
 }
 
diff --git a/oxide-api/src/util.ts b/oxide-api/src/util.ts
index a4438bd..5848e34 100644
--- a/oxide-api/src/util.ts
+++ b/oxide-api/src/util.ts
@@ -45,18 +45,9 @@ export const mapObj =
     return newObj;
   };
 
-export const parseIfDate = (k: string | undefined, v: unknown) => {
-  if (typeof v === "string" && (k?.startsWith("time_") || k === "timestamp")) {
-    const d = new Date(v);
-    if (isNaN(d.getTime())) return v;
-    return d;
-  }
-  return v;
-};
+export const snakeifyKeys = mapObj(camelToSnake);
 
-export const snakeify = mapObj(camelToSnake);
-
-export const processResponseBody = mapObj(snakeToCamel, parseIfDate);
+export const camelifyKeys = mapObj(snakeToCamel);
 
 export function isNotNull<T>(value: T): value is NonNullable<T> {
   return value != null;
diff --git a/oxide-openapi-gen-ts/src/client/api.test.ts b/oxide-openapi-gen-ts/src/client/api.test.ts
new file mode 100644
index 0000000..2a81ab3
--- /dev/null
+++ b/oxide-openapi-gen-ts/src/client/api.test.ts
@@ -0,0 +1,88 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * Copyright Oxide Computer Company
+ */
+import { describe, expect, it } from "vitest";
+import { genTransformResponse } from "./api";
+import { type OpenAPIV3 } from "openapi-types";
+
+const projectSchema = {
+  description: "View of a Project",
+  type: "object",
+  properties: {
+    description: {
+      description: "human-readable free-form text about a resource",
+      type: "string",
+    },
+    id: {
+      description:
+        "unique, immutable, system-controlled identifier for each resource",
+      type: "string",
+      format: "uuid",
+    },
+    name: {
+      description:
+        "unique, mutable, user-controlled identifier for each resource",
+      allOf: [Array],
+    },
+    time_created: {
+      description: "timestamp when this resource was created",
+      type: "string",
+      format: "date-time",
+    },
+    time_modified: {
+      description: "timestamp when this resource was last modified",
+      type: "string",
+      format: "date-time",
+    },
+  },
+  required: ["description", "id", "name", "time_created", "time_modified"],
+};
+
+// TODO: add array and nested object properties
+const noTransforms = {
+  description: "View of a Project",
+  type: "object",
+  properties: {
+    description: {
+      description: "human-readable free-form text about a resource",
+      type: "string",
+    },
+    id: {
+      description:
+        "unique, immutable, system-controlled identifier for each resource",
+      type: "string",
+      format: "uuid",
+    },
+    name: {
+      description:
+        "unique, mutable, user-controlled identifier for each resource",
+      allOf: [Array],
+    },
+  },
+  required: ["description", "id", "name"],
+};
+
+const spec: OpenAPIV3.Document = {
+  openapi: "",
+  info: { title: "", version: "" },
+  paths: {},
+};
+
+describe("generateTransformFunction", () => {
+  it("handles timestamps at top level", () => {
+    expect(genTransformResponse(spec, projectSchema)).toMatchInlineSnapshot(`
+      "(o) => {
+      o.time_created = new Date(o.time_created)
+      o.time_modified = new Date(o.time_modified)
+      }"
+    `);
+  });
+
+  it("returns null when there are no transforms to make", () => {
+    expect(genTransformResponse(spec, noTransforms)).toEqual(undefined);
+  });
+});
diff --git a/oxide-openapi-gen-ts/src/client/api.ts b/oxide-openapi-gen-ts/src/client/api.ts
index c24ac74..2c0c55e 100644
--- a/oxide-openapi-gen-ts/src/client/api.ts
+++ b/oxide-openapi-gen-ts/src/client/api.ts
@@ -22,7 +22,7 @@ import {
   snakeToPascal,
 } from "../util";
 import { initIO } from "../io";
-import type { Schema } from "../schema/base";
+import { refToSchemaName, type Schema } from "../schema/base";
 import {
   contentRef,
   docComment,
@@ -276,6 +276,18 @@ export function generateApi(spec: OpenAPIV3.Document, destDir: string) {
     if (queryParams.length > 0) {
       w("  query,");
     }
+
+    if (successType) {
+      // insert transformResponse if necessary
+      const schema = spec.components!.schemas![successType];
+      if (schema && "properties" in schema && schema.properties) {
+        const transformResponse = genTransformResponse(spec, schema);
+        if (transformResponse) {
+          w0("transformResponse: " + genTransformResponse(spec, schema) + ",");
+        }
+      }
+    }
+
     w(`  ...params,
          })
       },`);
@@ -336,3 +348,52 @@ export function generateApi(spec: OpenAPIV3.Document, destDir: string) {
    export default Api;`);
   out.end();
 }
+
+// TODO: special case for the common transform function that just does the
+// created and modified timestamps, could save a lot of lines
+export function genTransformResponse(
+  spec: OpenAPIV3.Document,
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  schema: any
+): string | undefined {
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  function recurse(schema: any, path: string): string | undefined {
+    if (schema.type === "object") {
+      const properties = Object.entries(schema.properties || {})
+        .map(([key, propSchema]) => {
+          const propPath = path ? `${path}.${key}` : key;
+          const transformCode = recurse(propSchema, propPath);
+          return transformCode ? `o.${key} = ${transformCode}` : undefined;
+        })
+        .filter((x) => x);
+      if (properties.length === 0) return undefined;
+
+      return properties.join("\n");
+    } else if (schema.type === "array") {
+      const transformCode = recurse(schema.items, "");
+      return transformCode
+        ? `o.${path}.map((o: any) => {
+  ${transformCode}
+  return o
+})`
+        : undefined;
+    } else if (schema.type === "string") {
+      if (schema.format === "date-time") {
+        return `new Date(o.${path})`;
+      } else if (schema.format === "uint128") {
+        return `BigInt(o.${path})`;
+      }
+    } else if ("$ref" in schema) {
+      const schemaName = refToSchemaName(schema.$ref);
+      const _schema = spec.components!.schemas![schemaName];
+      return recurse(_schema, path);
+    }
+    return undefined;
+  }
+
+  const transformCode = recurse(schema, "");
+  if (!transformCode) return undefined;
+  return `(o) => {
+${transformCode}
+}`;
+}
diff --git a/oxide-openapi-gen-ts/src/client/msw-handlers.ts b/oxide-openapi-gen-ts/src/client/msw-handlers.ts
index a28a90d..30c4320 100644
--- a/oxide-openapi-gen-ts/src/client/msw-handlers.ts
+++ b/oxide-openapi-gen-ts/src/client/msw-handlers.ts
@@ -43,7 +43,7 @@ export function generateMSWHandlers(spec: OpenAPIV3.Document, destDir: string) {
     import type { SnakeCasedPropertiesDeep as Snakify, Promisable } from "type-fest";
     import { type ZodSchema } from "zod";
     import type * as Api from "./Api";
-    import { snakeify } from "./util";
+    import { snakeifyKeys } from "./util";
     import * as schema from "./validate";
 
     type HandlerResult<T> = Json<T> | StrictResponse<Json<T>>;
@@ -90,10 +90,10 @@ export function generateMSWHandlers(spec: OpenAPIV3.Document, destDir: string) {
         ? `body: Json<Api.${bodyType}>,`
         : "";
     const pathParams = conf.parameters?.filter(
-      (param) => "name" in param && param.schema && param.in === "path",
+      (param) => "name" in param && param.schema && param.in === "path"
     );
     const queryParams = conf.parameters?.filter(
-      (param) => "name" in param && param.schema && param.in === "query",
+      (param) => "name" in param && param.schema && param.in === "query"
     );
     const pathParamsType = pathParams?.length
       ? `path: Api.${snakeToPascal(opId)}PathParams,`
@@ -159,7 +159,7 @@ export function generateMSWHandlers(spec: OpenAPIV3.Document, destDir: string) {
         let body = undefined
         if (bodySchema) {
           const rawBody = await req.json()
-          const result = bodySchema.transform(snakeify).safeParse(rawBody);
+          const result = bodySchema.transform(snakeifyKeys).safeParse(rawBody);
           if (!result.success) {
             const message = 'Zod error for body: ' + JSON.stringify(result.error)
             return json({ error_code: 'InvalidRequest', message }, { status: 400 })
@@ -222,8 +222,8 @@ export function generateMSWHandlers(spec: OpenAPIV3.Document, destDir: string) {
 
     w(
       `http.${method}('${formatPath(
-        path,
-      )}', handler(handlers['${handler}'], ${paramSchema}, ${bodySchema})),`,
+        path
+      )}', handler(handlers['${handler}'], ${paramSchema}, ${bodySchema})),`
     );
   }
   w(`]}`);
diff --git a/oxide-openapi-gen-ts/src/client/static/http-client.test.ts b/oxide-openapi-gen-ts/src/client/static/http-client.test.ts
index ae75d50..4a01945 100644
--- a/oxide-openapi-gen-ts/src/client/static/http-client.test.ts
+++ b/oxide-openapi-gen-ts/src/client/static/http-client.test.ts
@@ -52,9 +52,11 @@ describe("handleResponse", () => {
     expect(response.headers.get("Content-Type")).toBe("application/json");
   });
 
-  it("parses dates and converts to camel case", async () => {
+  it("parses dates and applies transformResponse", async () => {
     const resp = json({ time_created: "2022-05-01" });
-    const { response, ...rest } = await handleResponse(resp);
+    const { response, ...rest } = await handleResponse(resp, (o) => {
+      o.time_created = new Date(o.time_created);
+    });
     expect(rest).toMatchObject({
       type: "success",
       data: {
@@ -64,7 +66,7 @@ describe("handleResponse", () => {
     expect(response.headers.get("Content-Type")).toBe("application/json");
   });
 
-  it("leaves unparseable dates alone", async () => {
+  it("doesn't try to parse dates if there is no transformResponse", async () => {
     const resp = json({ time_created: "abc" });
     const { response, ...rest } = await handleResponse(resp);
     expect(rest).toMatchObject({
diff --git a/oxide-openapi-gen-ts/src/client/static/http-client.ts b/oxide-openapi-gen-ts/src/client/static/http-client.ts
index 4cf3a72..5fcc332 100644
--- a/oxide-openapi-gen-ts/src/client/static/http-client.ts
+++ b/oxide-openapi-gen-ts/src/client/static/http-client.ts
@@ -6,7 +6,7 @@
  * Copyright Oxide Computer Company
  */
 
-import { camelToSnake, processResponseBody, snakeify, isNotNull } from "./util";
+import { camelToSnake, snakeifyKeys, isNotNull, camelifyKeys } from "./util";
 
 /** Success responses from the API */
 export type ApiSuccess<Data> = {
@@ -61,7 +61,9 @@ function encodeQueryParam(key: string, value: unknown) {
 }
 
 export async function handleResponse<Data>(
-  response: Response
+  response: Response,
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  transformResponse?: (o: any) => void
 ): Promise<ApiResult<Data>> {
   const respText = await response.text();
 
@@ -70,8 +72,13 @@ export async function handleResponse<Data>(
   try {
     // don't bother trying to parse empty responses like 204s
     // TODO: is empty object what we want here?
-    respJson =
-      respText.length > 0 ? processResponseBody(JSON.parse(respText)) : {};
+    if (respText.length > 0) {
+      respJson = JSON.parse(respText);
+      transformResponse?.(respJson); // no assignment because this mutates the object
+      respJson = camelifyKeys(respJson);
+    } else {
+      respJson = {};
+    }
   } catch (e) {
     return {
       type: "client_error",
@@ -115,6 +122,8 @@ export interface FullParams extends FetchParams {
   body?: unknown;
   host?: string;
   method?: string;
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  transformResponse?: (o: any) => void;
 }
 
 export interface ApiConfig {
@@ -148,14 +157,15 @@ export class HttpClient {
     path,
     query,
     host,
+    transformResponse,
     ...fetchParams
   }: FullParams): Promise<ApiResult<Data>> {
     const url = (host || this.host) + path + toQueryString(query);
     const init = {
       ...mergeParams(this.baseParams, fetchParams),
-      body: JSON.stringify(snakeify(body), replacer),
+      body: JSON.stringify(snakeifyKeys(body), replacer),
     };
-    return handleResponse(await fetch(url, init));
+    return handleResponse(await fetch(url, init), transformResponse);
   }
 }
 
diff --git a/oxide-openapi-gen-ts/src/client/static/util.test.ts b/oxide-openapi-gen-ts/src/client/static/util.test.ts
index 9a1f1ff..8de8995 100644
--- a/oxide-openapi-gen-ts/src/client/static/util.test.ts
+++ b/oxide-openapi-gen-ts/src/client/static/util.test.ts
@@ -7,12 +7,11 @@
  */
 
 import {
+  camelifyKeys,
   camelToSnake,
   isObjectOrArray,
   mapObj,
-  parseIfDate,
-  processResponseBody,
-  snakeify,
+  snakeifyKeys,
   snakeToCamel,
   uniqueItems,
 } from "./util";
@@ -60,8 +59,8 @@ describe("mapObj", () => {
   });
 });
 
-test("processResponseBody", () => {
-  expect(processResponseBody({})).toEqual({});
+test("camelifyKeys", () => {
+  expect(camelifyKeys({})).toEqual({});
 
   const date = new Date();
   const dateStr = date.toISOString();
@@ -70,45 +69,14 @@ test("processResponseBody", () => {
     another_prop: "abc",
     time_created: dateStr,
   };
-  expect(processResponseBody(resp)).toMatchObject({
+  expect(camelifyKeys(resp)).toMatchObject({
     id: "big-uuid",
     anotherProp: "abc",
-    timeCreated: expect.any(Date),
+    timeCreated: dateStr,
   });
 });
 
-describe("parseIfDate", () => {
-  it("passes through non-date values", () => {
-    expect(parseIfDate("abc", 123)).toEqual(123);
-    expect(parseIfDate("abc", "def")).toEqual("def");
-  });
-
-  const timestamp = 1643092429315;
-  const dateStr = new Date(timestamp).toISOString();
-
-  it("doesn't parse dates if key doesn't start with time_", () => {
-    expect(parseIfDate("abc", dateStr)).toEqual(dateStr);
-  });
-
-  it("parses dates if key starts with time_", () => {
-    const value = parseIfDate("time_whatever", dateStr);
-    expect(value).toBeInstanceOf(Date);
-    expect((value as Date).getTime()).toEqual(timestamp);
-  });
-
-  it("parses dates if key = 'timestamp'", () => {
-    const value = parseIfDate("timestamp", dateStr);
-    expect(value).toBeInstanceOf(Date);
-    expect((value as Date).getTime()).toEqual(timestamp);
-  });
-
-  it("passes through values that fail to parse as dates", () => {
-    const value = parseIfDate("time_whatever", "blah");
-    expect(value).toEqual("blah");
-  });
-});
-
-test("snakeify", () => {
+test("snakeifyKeys", () => {
   const obj = {
     id: "vpc-id",
     timeCreated: new Date(Date.UTC(2021, 0, 1)).toISOString(),
@@ -119,7 +87,7 @@ test("snakeify", () => {
       weAreSerious: "xyz",
     },
   };
-  expect(snakeify(obj)).toMatchInlineSnapshot(`
+  expect(snakeifyKeys(obj)).toMatchInlineSnapshot(`
     {
       "id": "vpc-id",
       "nested_obj": {
diff --git a/oxide-openapi-gen-ts/src/client/static/util.ts b/oxide-openapi-gen-ts/src/client/static/util.ts
index 21cf097..e9014ee 100644
--- a/oxide-openapi-gen-ts/src/client/static/util.ts
+++ b/oxide-openapi-gen-ts/src/client/static/util.ts
@@ -45,18 +45,9 @@ export const mapObj =
     return newObj;
   };
 
-export const parseIfDate = (k: string | undefined, v: unknown) => {
-  if (typeof v === "string" && (k?.startsWith("time_") || k === "timestamp")) {
-    const d = new Date(v);
-    if (isNaN(d.getTime())) return v;
-    return d;
-  }
-  return v;
-};
+export const snakeifyKeys = mapObj(camelToSnake);
 
-export const snakeify = mapObj(camelToSnake);
-
-export const processResponseBody = mapObj(snakeToCamel, parseIfDate);
+export const camelifyKeys = mapObj(snakeToCamel);
 
 export function isNotNull<T>(value: T): value is NonNullable<T> {
   return value != null;
diff --git a/oxide-openapi-gen-ts/src/client/zodValidators.ts b/oxide-openapi-gen-ts/src/client/zodValidators.ts
index 51ba3f8..c983816 100644
--- a/oxide-openapi-gen-ts/src/client/zodValidators.ts
+++ b/oxide-openapi-gen-ts/src/client/zodValidators.ts
@@ -38,7 +38,7 @@ export function generateZodValidators(
    */
 
   import { z, ZodType } from 'zod';
-  import { processResponseBody, uniqueItems } from './util';
+  import { camelifyKeys, uniqueItems } from './util';
 
   /**
    * Zod only supports string enums at the moment. A previous issue was opened
@@ -62,7 +62,7 @@ export function generateZodValidators(
       docComment(extractDoc(schema), schemaNames, io);
     }
 
-    w0(`export const ${schemaName} = z.preprocess(processResponseBody,`);
+    w0(`export const ${schemaName} = z.preprocess(camelifyKeys,`);
     schemaToZod(schema, io);
     w(")\n");
   }
@@ -76,9 +76,7 @@ export function generateZodValidators(
 
       const opName = snakeToPascal(conf.operationId);
       const params = conf.parameters;
-      w(
-        `export const ${opName}Params = z.preprocess(processResponseBody, z.object({`
-      );
+      w(`export const ${opName}Params = z.preprocess(camelifyKeys, z.object({`);
 
       w("  path: z.object({");
       for (const param of params || []) {