diff --git a/packages/cli/src/commands/conventions.integration.spec.ts b/packages/cli/src/commands/conventions.integration.spec.ts
index 4e44325..ab7faa2 100644
--- a/packages/cli/src/commands/conventions.integration.spec.ts
+++ b/packages/cli/src/commands/conventions.integration.spec.ts
@@ -134,7 +134,7 @@ describe("architecture and practices facets integration", () => {
     // Facet order: process (select), architecture (select), practices (multiselect)
     vi.mocked(clack.select)
       .mockResolvedValueOnce("native-agents-md") // process
-      .mockResolvedValueOnce("__skip__"); // architecture: skip
+      .mockResolvedValueOnce("other"); // architecture: other
     vi.mocked(clack.multiselect)
       .mockResolvedValueOnce(["conventional-commits", "tdd-london"]) // practices
       .mockResolvedValueOnce(["claude-code"]); // harnesses
@@ -182,7 +182,7 @@ describe("architecture and practices facets integration", () => {
     // Facet order: process (select), architecture (select), practices (multiselect)
     vi.mocked(clack.select)
       .mockResolvedValueOnce("native-agents-md") // process
-      .mockResolvedValueOnce("__skip__"); // architecture: skip
+      .mockResolvedValueOnce("other"); // architecture: other
     vi.mocked(clack.multiselect)
       .mockResolvedValueOnce(["adr-nygard"])
       .mockResolvedValueOnce(["claude-code"]); // harnesses
@@ -199,13 +199,13 @@ describe("architecture and practices facets integration", () => {
     expect(adr).toContain("## Consequences");
   });
 
-  it("skips both architecture and practices when none selected", async () => {
+  it("writes no .ade directory when architecture is other and no practices selected", async () => {
     const catalog = getDefaultCatalog();
 
     // Facet order: process (select), architecture (select), practices (multiselect)
     vi.mocked(clack.select)
       .mockResolvedValueOnce("native-agents-md") // process
-      .mockResolvedValueOnce("__skip__"); // architecture: skip
+      .mockResolvedValueOnce("other"); // architecture: other
     vi.mocked(clack.multiselect)
       .mockResolvedValueOnce([]) // practices: none
       .mockResolvedValueOnce(["claude-code"]); // harnesses
@@ -215,9 +215,9 @@ describe("architecture and practices facets integration", () => {
     // No .ade directory should exist
     await expect(access(join(dir, ".ade"))).rejects.toThrow();
 
-    // config.yaml should not have architecture or practices keys
+    // config.yaml should have architecture: "other" but no practices key
     const config = await readUserConfig(dir);
-    expect(config!.choices).not.toHaveProperty("architecture");
+    expect(config!.choices).toHaveProperty("architecture", "other");
     expect(config!.choices).not.toHaveProperty("practices");
   });
 
@@ -227,7 +227,7 @@ describe("architecture and practices facets integration", () => {
     // Facet order: process (select), architecture (select), practices (multiselect)
     vi.mocked(clack.select)
       .mockResolvedValueOnce("native-agents-md") // process
-      .mockResolvedValueOnce("__skip__"); // architecture: skip
+      .mockResolvedValueOnce("other"); // architecture: other
     vi.mocked(clack.multiselect)
       .mockResolvedValueOnce(["tdd-london"])
       .mockResolvedValueOnce(["claude-code"]); // harnesses
diff --git a/packages/cli/src/commands/install.integration.spec.ts b/packages/cli/src/commands/install.integration.spec.ts
index c56d0da..c8c3579 100644
--- a/packages/cli/src/commands/install.integration.spec.ts
+++ b/packages/cli/src/commands/install.integration.spec.ts
@@ -46,7 +46,7 @@ describe("install integration (real temp dir)", () => {
     // Step 1: Run setup to create config.yaml + config.lock.yaml
     vi.mocked(clack.select)
       .mockResolvedValueOnce("codemcp-workflows") // process
-      .mockResolvedValueOnce("__skip__"); // architecture
+      .mockResolvedValueOnce("other"); // architecture
     vi.mocked(clack.multiselect).mockResolvedValueOnce([]); // practices: none
     await runSetup(dir, catalog);
 
@@ -73,7 +73,7 @@ describe("install integration (real temp dir)", () => {
     // Setup first
     vi.mocked(clack.select)
       .mockResolvedValueOnce("codemcp-workflows") // process
-      .mockResolvedValueOnce("__skip__"); // architecture
+      .mockResolvedValueOnce("other"); // architecture
     vi.mocked(clack.multiselect).mockResolvedValueOnce([]); // practices: none
     await runSetup(dir, catalog);
 
@@ -102,7 +102,7 @@ describe("install integration (real temp dir)", () => {
     // Setup with native-agents-md
     vi.mocked(clack.select)
       .mockResolvedValueOnce("native-agents-md") // process
-      .mockResolvedValueOnce("__skip__"); // architecture
+      .mockResolvedValueOnce("other"); // architecture
     vi.mocked(clack.multiselect).mockResolvedValueOnce([]); // practices: none
     await runSetup(dir, catalog);
 
diff --git a/packages/cli/src/commands/knowledge.integration.spec.ts b/packages/cli/src/commands/knowledge.integration.spec.ts
index e36a9aa..1ec7b49 100644
--- a/packages/cli/src/commands/knowledge.integration.spec.ts
+++ b/packages/cli/src/commands/knowledge.integration.spec.ts
@@ -95,7 +95,7 @@ describe("knowledge integration", () => {
 
     vi.mocked(clack.select)
       .mockResolvedValueOnce("native-agents-md") // process
-      .mockResolvedValueOnce("__skip__"); // architecture: skip
+      .mockResolvedValueOnce("other"); // architecture: other
     vi.mocked(clack.multiselect).mockResolvedValueOnce(["tdd-london"]); // practices: tdd-london has no docsets
 
     await runSetup(dir, catalog);
diff --git a/packages/cli/src/commands/setup.integration.spec.ts b/packages/cli/src/commands/setup.integration.spec.ts
index f381f14..0c9011c 100644
--- a/packages/cli/src/commands/setup.integration.spec.ts
+++ b/packages/cli/src/commands/setup.integration.spec.ts
@@ -45,7 +45,7 @@ describe("setup integration (real temp dir)", () => {
 
     vi.mocked(clack.select)
       .mockResolvedValueOnce("codemcp-workflows") // process
-      .mockResolvedValueOnce("__skip__"); // architecture
+      .mockResolvedValueOnce("other"); // architecture
     vi.mocked(clack.multiselect).mockResolvedValueOnce([]); // practices: none
 
     await runSetup(dir, catalog);
@@ -53,7 +53,10 @@ describe("setup integration (real temp dir)", () => {
     // ── config.yaml ──────────────────────────────────────────────────────
     const config = await readUserConfig(dir);
     expect(config).not.toBeNull();
-    expect(config!.choices).toEqual({ process: "codemcp-workflows" });
+    expect(config!.choices).toEqual({
+      process: "codemcp-workflows",
+      architecture: "other"
+    });
     // harnesses must NOT be in config.yaml — setup no longer selects them
     expect(config).not.toHaveProperty("harnesses");
 
@@ -61,7 +64,10 @@ describe("setup integration (real temp dir)", () => {
     const lock = await readLockFile(dir);
     expect(lock).not.toBeNull();
     expect(lock!.version).toBe(1);
-    expect(lock!.choices).toEqual({ process: "codemcp-workflows" });
+    expect(lock!.choices).toEqual({
+      process: "codemcp-workflows",
+      architecture: "other"
+    });
     expect(lock!.generated_at).toBeTruthy();
     // harnesses must NOT be in the lock file
     expect(lock).not.toHaveProperty("harnesses");
@@ -78,16 +84,22 @@ describe("setup integration (real temp dir)", () => {
 
     vi.mocked(clack.select)
       .mockResolvedValueOnce("native-agents-md") // process
-      .mockResolvedValueOnce("__skip__"); // architecture
+      .mockResolvedValueOnce("other"); // architecture
     vi.mocked(clack.multiselect).mockResolvedValueOnce([]); // practices: none
 
     await runSetup(dir, catalog);
 
     const config = await readUserConfig(dir);
-    expect(config!.choices).toEqual({ process: "native-agents-md" });
+    expect(config!.choices).toEqual({
+      process: "native-agents-md",
+      architecture: "other"
+    });
 
     const lock = await readLockFile(dir);
-    expect(lock!.choices).toEqual({ process: "native-agents-md" });
+    expect(lock!.choices).toEqual({
+      process: "native-agents-md",
+      architecture: "other"
+    });
     expect(lock!.logical_config.instructions.length).toBeGreaterThan(0);
   });
 
@@ -112,7 +124,7 @@ describe("setup integration (real temp dir)", () => {
 
     vi.mocked(clack.select)
       .mockResolvedValueOnce("codemcp-workflows") // process
-      .mockResolvedValueOnce("__skip__"); // architecture
+      .mockResolvedValueOnce("other"); // architecture
     vi.mocked(clack.multiselect).mockResolvedValueOnce([]); // practices: none
 
     await runSetup(dir, catalog);
diff --git a/packages/cli/src/commands/setup.ts b/packages/cli/src/commands/setup.ts
index 0ab1ffa..ded77cf 100644
--- a/packages/cli/src/commands/setup.ts
+++ b/packages/cli/src/commands/setup.ts
@@ -194,7 +194,7 @@ function promptSelect(
     hint: o.description
   }));
 
-  if (!facet.required) {
+  if (!facet.required && !facet.options.some((o) => o.id === "other")) {
     options.push({ value: "__skip__", label: "Skip", hint: "" });
   }
 
diff --git a/packages/core/src/catalog/facets/architecture.ts b/packages/core/src/catalog/facets/architecture.ts
index f1647b6..2b5149f 100644
--- a/packages/core/src/catalog/facets/architecture.ts
+++ b/packages/core/src/catalog/facets/architecture.ts
@@ -464,6 +464,13 @@ export const architectureFacet: Facet = {
           }
         }
       ]
+    },
+    {
+      id: "other",
+      label: "Other",
+      description:
+        "Custom or unlisted architecture — no conventions will be applied",
+      recipe: []
     }
   ]
 };