diff --git a/apps/server/src/vcs/VcsProjectConfig.test.ts b/apps/server/src/vcs/VcsProjectConfig.test.ts
index aac4beb7e32..a54ef2541e1 100644
--- a/apps/server/src/vcs/VcsProjectConfig.test.ts
+++ b/apps/server/src/vcs/VcsProjectConfig.test.ts
@@ -41,8 +41,7 @@ describe("VcsProjectConfig", () => {
         yield* fileSystem.makeDirectory(nested, { recursive: true });
         yield* fileSystem.writeFileString(
           path.join(configDir, "vcs.json"),
-          // @effect-diagnostics-next-line preferSchemaOverJson:off
-          JSON.stringify({ vcs: { kind: "jj" } }),
+          '{"vcs":{"kind":"jj"}}',
         );
 
         const config = yield* VcsProjectConfig.VcsProjectConfig;
@@ -53,6 +52,26 @@ describe("VcsProjectConfig", () => {
     );
   });
 
+  it.layer(TestLayer)("ignores malformed .t3code/vcs.json files", (it) => {
+    it.effect("falls back to auto", () =>
+      Effect.gen(function* () {
+        const fileSystem = yield* FileSystem.FileSystem;
+        const path = yield* Path.Path;
+        const root = yield* fileSystem.makeTempDirectoryScoped({
+          prefix: "t3-vcs-config-test-",
+        });
+        const configDir = path.join(root, ".t3code");
+        yield* fileSystem.makeDirectory(configDir, { recursive: true });
+        yield* fileSystem.writeFileString(path.join(configDir, "vcs.json"), "{ not-json");
+
+        const config = yield* VcsProjectConfig.VcsProjectConfig;
+        const kind = yield* config.resolveKind({ cwd: root });
+
+        assert.equal(kind, "auto");
+      }),
+    );
+  });
+
   it.layer(TestLayer)("falls back to auto when no config exists", (it) => {
     it.effect("returns auto", () =>
       Effect.gen(function* () {
diff --git a/apps/server/src/vcs/VcsProjectConfig.ts b/apps/server/src/vcs/VcsProjectConfig.ts
index 3e5ee2347ce..2a6d6513ddf 100644
--- a/apps/server/src/vcs/VcsProjectConfig.ts
+++ b/apps/server/src/vcs/VcsProjectConfig.ts
@@ -2,6 +2,7 @@ import * as Context from "effect/Context";
 import * as Effect from "effect/Effect";
 import * as FileSystem from "effect/FileSystem";
 import * as Layer from "effect/Layer";
+import * as Option from "effect/Option";
 import * as Path from "effect/Path";
 import * as Schema from "effect/Schema";
 
@@ -15,16 +16,10 @@ const ProjectVcsConfig = Schema.Struct({
   ),
   vcsKind: Schema.optional(VcsDriverKind),
 });
-const isProjectVcsConfig = Schema.is(ProjectVcsConfig);
+const ProjectVcsConfigJson = Schema.fromJsonString(ProjectVcsConfig);
+const decodeProjectVcsConfig = Schema.decodeUnknownOption(ProjectVcsConfigJson);
 
-interface ProjectVcsConfigFile {
-  readonly vcs?:
-    | {
-        readonly kind?: VcsDriverKindType | undefined;
-      }
-    | undefined;
-  readonly vcsKind?: VcsDriverKindType | undefined;
-}
+type ProjectVcsConfigFile = Schema.Schema.Type<typeof ProjectVcsConfig>;
 
 export interface VcsProjectConfigResolveInput {
   readonly cwd: string;
@@ -45,13 +40,8 @@ function configuredKind(config: ProjectVcsConfigFile): VcsDriverKindType | "auto
   return config.vcs?.kind ?? config.vcsKind ?? "auto";
 }
 
-function parseConfig(raw: string): ProjectVcsConfigFile | null {
-  try {
-    const parsed = JSON.parse(raw) as unknown;
-    return isProjectVcsConfig(parsed) ? parsed : null;
-  } catch {
-    return null;
-  }
+function parseConfig(raw: string): Option.Option<ProjectVcsConfigFile> {
+  return decodeProjectVcsConfig(raw);
 }
 
 export const make = Effect.fn("makeVcsProjectConfig")(function* () {
@@ -63,12 +53,12 @@ export const make = Effect.fn("makeVcsProjectConfig")(function* () {
     while (true) {
       const candidate = path.join(current, ".t3code", "vcs.json");
       if (yield* fileSystem.exists(candidate).pipe(Effect.orElseSucceed(() => false))) {
-        return candidate;
+        return Option.some(candidate);
       }
 
       const parent = path.dirname(current);
       if (parent === current) {
-        return null;
+        return Option.none<string>();
       }
       current = parent;
     }
@@ -78,26 +68,27 @@ export const make = Effect.fn("makeVcsProjectConfig")(function* () {
     configPath: string,
   ) {
     const raw = yield* fileSystem.readFileString(configPath).pipe(
+      Effect.map(Option.some),
       Effect.catch((error) =>
         Effect.logWarning("failed to read VCS project config", {
           configPath,
           error,
-        }).pipe(Effect.as(null)),
+        }).pipe(Effect.as(Option.none<string>())),
       ),
     );
-    if (raw === null) {
+    if (Option.isNone(raw)) {
       return "auto" as const;
     }
 
-    const parsed = parseConfig(raw);
-    if (parsed === null) {
+    const parsed = parseConfig(raw.value);
+    if (Option.isNone(parsed)) {
       yield* Effect.logWarning("invalid VCS project config", {
         configPath,
       });
       return "auto" as const;
     }
 
-    return configuredKind(parsed);
+    return configuredKind(parsed.value);
   });
 
   const resolveKind: VcsProjectConfigShape["resolveKind"] = Effect.fn(
@@ -108,11 +99,11 @@ export const make = Effect.fn("makeVcsProjectConfig")(function* () {
     }
 
     const configPath = yield* findConfigPath(input.cwd);
-    if (configPath === null) {
+    if (Option.isNone(configPath)) {
       return "auto";
     }
 
-    return yield* readConfiguredKind(configPath);
+    return yield* readConfiguredKind(configPath.value);
   });
 
   return VcsProjectConfig.of({
diff --git a/apps/server/src/workspace/Layers/WorkspaceEntries.ts b/apps/server/src/workspace/Layers/WorkspaceEntries.ts
index 0c0ab638207..235bd717bbe 100644
--- a/apps/server/src/workspace/Layers/WorkspaceEntries.ts
+++ b/apps/server/src/workspace/Layers/WorkspaceEntries.ts
@@ -29,7 +29,7 @@ import {
 } from "../Services/WorkspaceEntries.ts";
 import { WorkspacePaths } from "../Services/WorkspacePaths.ts";
 
-const WORKSPACE_CACHE_TTL_MS = 15_000;
+const WORKSPACE_CACHE_TTL = Duration.seconds(15);
 const WORKSPACE_CACHE_MAX_KEYS = 4;
 const WORKSPACE_INDEX_MAX_ENTRIES = 25_000;
 const WORKSPACE_SCAN_READDIR_CONCURRENCY = 32;
@@ -402,8 +402,7 @@ export const makeWorkspaceEntries = Effect.gen(function* () {
     buildWorkspaceIndex,
     {
       capacity: WORKSPACE_CACHE_MAX_KEYS,
-      timeToLive: (exit) =>
-        Exit.isSuccess(exit) ? Duration.millis(WORKSPACE_CACHE_TTL_MS) : Duration.zero,
+      timeToLive: (exit) => (Exit.isSuccess(exit) ? WORKSPACE_CACHE_TTL : Duration.zero),
     },
   );