fix(zig): two more Zig 0.15 API fixes — callconv(.C) + http response writer

- 22 FFI files: strip `callconv(.C)` from `pub export fn` signatures
  (in Zig 0.15 CallingConvention.C was removed; callconv is implicit on export)
- 4 http FFI files: replace ArrayList.init + response_storage union with
  std.Io.Writer.Allocating + response_writer field
  (Zig 0.15 replaced FetchOptions.response_storage union with response_writer: ?*Writer;
   ArrayList is now unmanaged and has no init; use Io.Writer.Allocating.init instead)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: hyperpolymath

cartridges/aerie-mcp/ffi/aerie_ffi.zig

@@ -6,24 +6,24 @@
 const std = @import("std");
 
 /// List active environment count.
-export fn aerie_list_envs_count() callconv(.C) u32 {
+export fn aerie_list_envs_count() u32 {
     return 0; // Stub
 }
 
 /// Create an environment. Returns env ID or 0 on failure.
-export fn aerie_create_env(name: [*c]const u8, mem_mb: u32) callconv(.C) u32 {
+export fn aerie_create_env(name: [*c]const u8, mem_mb: u32) u32 {
     if (name == null or mem_mb == 0) return 0;
     return 1; // Stub
 }
 
 /// Destroy an environment. Returns 0 on success.
-export fn aerie_destroy_env(env_id: u32) callconv(.C) i32 {
+export fn aerie_destroy_env(env_id: u32) i32 {
     if (env_id == 0) return -1;
     return 0; // Stub
 }
 
 /// Get env status: 0=provisioning, 1=ready, 2=destroying, 3=destroyed, 4=error.
-export fn aerie_get_status(env_id: u32) callconv(.C) u8 {
+export fn aerie_get_status(env_id: u32) u8 {
     if (env_id == 0) return 4; // Error
     return 1; // Stub — ready
 }

cartridges/burble-admin-mcp/ffi/burble_admin_ffi.zig

@@ -32,7 +32,7 @@ pub const PermLevel = enum(i32) {
 
 /// Returns the minimum permission level for an operation.
 /// Matches burble_min_perm in Protocol.idr exactly.
-pub export fn burble_admin_min_perm(op: i32) callconv(.C) i32 {
+pub export fn burble_admin_min_perm(op: i32) i32 {
     return switch (@as(Operation, @enumFromInt(op))) {
         .list_rooms => 0,
         .create_room => 1,
@@ -46,7 +46,7 @@ pub export fn burble_admin_min_perm(op: i32) callconv(.C) i32 {
 
 /// Check if a user with the given permission level can perform the operation.
 /// Returns 1 if allowed, 0 if denied.
-pub export fn burble_admin_check_perm(op: i32, user_perm: i32) callconv(.C) i32 {
+pub export fn burble_admin_check_perm(op: i32, user_perm: i32) i32 {
     const required = burble_admin_min_perm(op);
     return if (user_perm >= required) 1 else 0;
 }
@@ -56,7 +56,7 @@ pub export fn burble_admin_check_perm(op: i32, user_perm: i32) callconv(.C) i32
 // ═══════════════════════════════════════════════════════════════════════
 
 /// Validate room capacity (1-500). Returns clamped value.
-pub export fn burble_admin_clamp_capacity(requested: i32) callconv(.C) i32 {
+pub export fn burble_admin_clamp_capacity(requested: i32) i32 {
     if (requested < 1) return 1;
     if (requested > 500) return 500;
     return requested;

cartridges/civic-connect-mcp/ffi/civic_connect_ffi.zig

@@ -6,18 +6,18 @@
 const std = @import("std");
 
 /// List active channel count.
-export fn civic_connect_list_channels_count() callconv(.C) u32 {
+export fn civic_connect_list_channels_count() u32 {
     return 0; // Stub
 }
 
 /// Send a message to a channel. Returns 0 on success, -1 on error.
-export fn civic_connect_send_message(channel_id: u32, body: [*c]const u8) callconv(.C) i32 {
+export fn civic_connect_send_message(channel_id: u32, body: [*c]const u8) i32 {
     if (channel_id == 0 or body == null) return -1;
     return 0; // Stub
 }
 
 /// Get poll results. Returns total vote count, or 0 if poll not found.
-export fn civic_connect_get_poll(poll_id: u32) callconv(.C) u32 {
+export fn civic_connect_get_poll(poll_id: u32) u32 {
     if (poll_id == 0) return 0;
     return 0; // Stub
 }

cartridges/conflow-mcp/ffi/conflow_ffi.zig

@@ -6,25 +6,25 @@
 const std = @import("std");
 
 /// Get a config value by key. Returns 0 if found, -1 if missing.
-export fn conflow_get_config(key: [*c]const u8) callconv(.C) i32 {
+export fn conflow_get_config(key: [*c]const u8) i32 {
     if (key == null) return -1;
     return 0; // Stub
 }
 
 /// Apply a config blob. Returns number of entries applied, or -1 on error.
-export fn conflow_apply_config(blob: [*c]const u8) callconv(.C) i32 {
+export fn conflow_apply_config(blob: [*c]const u8) i32 {
     if (blob == null) return -1;
     return 0; // Stub
 }
 
 /// Validate a config blob. Returns 0 if valid, error count otherwise.
-export fn conflow_validate_config(blob: [*c]const u8) callconv(.C) i32 {
+export fn conflow_validate_config(blob: [*c]const u8) i32 {
     if (blob == null) return -1;
     return 0; // Stub — valid
 }
 
 /// Diff two config blobs. Returns number of differences.
-export fn conflow_diff_config(a: [*c]const u8, b: [*c]const u8) callconv(.C) u32 {
+export fn conflow_diff_config(a: [*c]const u8, b: [*c]const u8) u32 {
     if (a == null or b == null) return 0;
     return 0; // Stub
 }

cartridges/dns-shield-mcp/ffi/dns_shield_ffi.zig

@@ -57,7 +57,7 @@ export fn dns_shield_resolve_doq(
     domain: [*:0]const u8,
     record_type: RecordType,
     result: *DnsResult,
-) callconv(.C) i32 {
+) i32 {
     return resolve_encrypted(domain, record_type, .doq, result);
 }
 
@@ -66,7 +66,7 @@ export fn dns_shield_resolve_doh(
     domain: [*:0]const u8,
     record_type: RecordType,
     result: *DnsResult,
-) callconv(.C) i32 {
+) i32 {
     return resolve_encrypted(domain, record_type, .doh, result);
 }
 
@@ -75,7 +75,7 @@ export fn dns_shield_resolve_doh(
 export fn dns_shield_validate_dnssec(
     domain: [*:0]const u8,
     record_type: RecordType,
-) callconv(.C) DnssecState {
+) DnssecState {
     // DNSSEC validation requires checking RRSIG + DNSKEY chain.
     // For now, delegate to the system resolver's DNSSEC support
     // (most modern resolvers like systemd-resolved, Unbound, or
@@ -90,7 +90,7 @@ export fn dns_shield_validate_dnssec(
 export fn dns_shield_check_caa(
     domain: [*:0]const u8,
     ca_domain: [*:0]const u8,
-) callconv(.C) i32 {
+) i32 {
     _ = domain;
     _ = ca_domain;
     // CAA check: resolve CAA records, compare with ca_domain.
@@ -99,12 +99,12 @@ export fn dns_shield_check_caa(
 }
 
 /// Flush the DNS cache for all encrypted resolvers.
-export fn dns_shield_flush_cache() callconv(.C) void {
+export fn dns_shield_flush_cache() void {
     // Clear any cached DoQ/DoH responses.
 }
 
 /// Get the DNS Shield cartridge version.
-export fn dns_shield_version() callconv(.C) [*:0]const u8 {
+export fn dns_shield_version() [*:0]const u8 {
     return "0.5.0";
 }
 

cartridges/game-admin-mcp/ffi/game_admin_ffi.zig

@@ -22,7 +22,7 @@ pub const PermLevel = enum(i32) {
     admin = 2,
 };
 
-pub export fn game_admin_min_perm(op: i32) callconv(.C) i32 {
+pub export fn game_admin_min_perm(op: i32) i32 {
     return switch (@as(Operation, @enumFromInt(op))) {
         .list_servers => 0,
         .get_server_status => 0,
@@ -35,12 +35,12 @@ pub export fn game_admin_min_perm(op: i32) callconv(.C) i32 {
     };
 }
 
-pub export fn game_admin_check_perm(op: i32, user_perm: i32) callconv(.C) i32 {
+pub export fn game_admin_check_perm(op: i32, user_perm: i32) i32 {
     const required = game_admin_min_perm(op);
     return if (user_perm >= required) 1 else 0;
 }
 
-pub export fn game_admin_is_readonly(op: i32) callconv(.C) i32 {
+pub export fn game_admin_is_readonly(op: i32) i32 {
     return switch (@as(Operation, @enumFromInt(op))) {
         .list_servers, .get_server_status, .get_logs, .probe_health => 1,
         else => 0,

cartridges/github-api-mcp/ffi/github_api_mcp_ffi.zig

@@ -377,15 +377,15 @@ fn doHttpRequest(
     const http_method = parseHttpMethod(method);
 
     // Fetch the request (Zig 0.15 API — replaces open/send/wait)
-    var response_storage = std.ArrayList(u8).init(allocator);
-    defer response_storage.deinit();
+    var aw: std.Io.Writer.Allocating = .init(allocator);
+    defer aw.deinit();
 
     const fetch_result = client.fetch(.{
         .method = http_method,
         .location = .{ .uri = uri },
         .extra_headers = &headers_buf,
         .payload = body,
-        .response_storage = .{ .dynamic = &response_storage },
+        .response_writer = &aw.writer,
     }) catch return -5;
 
     // Handle rate limiting (HTTP 429 or 403 with depleted budget)
@@ -402,8 +402,9 @@ fn doHttpRequest(
     }
 
     // Copy response body into the caller's output buffer
-    const to_copy = @min(response_storage.items.len, out_cap);
-    @memcpy(out_buf[0..to_copy], response_storage.items[0..to_copy]);
+    const response_bytes = aw.writer.buffered();
+    const to_copy = @min(response_bytes.len, out_cap);
+    @memcpy(out_buf[0..to_copy], response_bytes[0..to_copy]);
     return @intCast(to_copy);
 }
 

cartridges/gitlab-api-mcp/ffi/gitlab_api_mcp_ffi.zig

@@ -330,15 +330,15 @@ pub export fn gitlab_api_mcp_request(
     } else null;
 
     // Fetch the request (Zig 0.15 API — replaces open/send/wait)
-    var response_storage = std.ArrayList(u8).init(allocator);
-    defer response_storage.deinit();
+    var aw: std.Io.Writer.Allocating = .init(allocator);
+    defer aw.deinit();
 
     const fetch_result = client.fetch(.{
         .method = http_method,
         .location = .{ .uri = uri },
         .extra_headers = &headers_buf,
         .payload = body_slice,
-        .response_storage = .{ .dynamic = &response_storage },
+        .response_writer = &aw.writer,
     }) catch return -4;
 
     // Handle rate limiting (HTTP 429)
@@ -350,8 +350,9 @@ pub export fn gitlab_api_mcp_request(
     }
 
     // Handle server errors
-    const bytes_read = @min(response_storage.items.len, cap);
-    @memcpy(out_buf[0..bytes_read], response_storage.items[0..bytes_read]);
+    const response_bytes = aw.writer.buffered();
+    const bytes_read = @min(response_bytes.len, cap);
+    @memcpy(out_buf[0..bytes_read], response_bytes[0..bytes_read]);
     out_len.* = @intCast(bytes_read);
 
     if (status_code >= 500) {
@@ -436,15 +437,15 @@ pub export fn gitlab_api_mcp_graphql(
     };
 
     // Fetch the request (Zig 0.15 API — replaces open/send/wait)
-    var response_storage = std.ArrayList(u8).init(allocator);
-    defer response_storage.deinit();
+    var aw: std.Io.Writer.Allocating = .init(allocator);
+    defer aw.deinit();
 
     const fetch_result = client.fetch(.{
         .method = .POST,
         .location = .{ .uri = uri },
         .extra_headers = &headers_buf,
         .payload = gql_body,
-        .response_storage = .{ .dynamic = &response_storage },
+        .response_writer = &aw.writer,
     }) catch return -4;
 
     const status_code = @intFromEnum(fetch_result.status);
@@ -454,8 +455,9 @@ pub export fn gitlab_api_mcp_graphql(
         return -3;
     }
 
-    const bytes_read = @min(response_storage.items.len, cap);
-    @memcpy(out_buf[0..bytes_read], response_storage.items[0..bytes_read]);
+    const response_bytes = aw.writer.buffered();
+    const bytes_read = @min(response_bytes.len, cap);
+    @memcpy(out_buf[0..bytes_read], response_bytes[0..bytes_read]);
     out_len.* = @intCast(bytes_read);
     return 0;
 }
@@ -528,15 +530,15 @@ pub export fn gitlab_api_mcp_setup_mirror(
     };
 
     // Fetch the request (Zig 0.15 API — replaces open/send/wait)
-    var response_storage = std.ArrayList(u8).init(allocator);
-    defer response_storage.deinit();
+    var aw: std.Io.Writer.Allocating = .init(allocator);
+    defer aw.deinit();
 
     const fetch_result = client.fetch(.{
         .method = .POST,
         .location = .{ .uri = uri },
         .extra_headers = &headers_buf_mirror,
         .payload = mirror_body,
-        .response_storage = .{ .dynamic = &response_storage },
+        .response_writer = &aw.writer,
     }) catch return -4;
 
     const status_code = @intFromEnum(fetch_result.status);
@@ -546,8 +548,9 @@ pub export fn gitlab_api_mcp_setup_mirror(
         return -3;
     }
 
-    const bytes_read = @min(response_storage.items.len, cap);
-    @memcpy(out_buf[0..bytes_read], response_storage.items[0..bytes_read]);
+    const response_bytes = aw.writer.buffered();
+    const bytes_read = @min(response_bytes.len, cap);
+    @memcpy(out_buf[0..bytes_read], response_bytes[0..bytes_read]);
     out_len.* = @intCast(bytes_read);
     return 0;
 }

cartridges/gossamer-mcp/ffi/gossamer_ffi.zig

@@ -9,26 +9,26 @@ const std = @import("std");
 pub const WindowHandle = u32;
 
 /// Create a new webview window. Returns handle or 0 on failure.
-export fn gossamer_create_window(width: u32, height: u32) callconv(.C) WindowHandle {
+export fn gossamer_create_window(width: u32, height: u32) WindowHandle {
     if (width == 0 or height == 0) return 0;
     // Stub: real impl delegates to libgossamer
     return 1;
 }
 
 /// Load a panel by URI into a window. Returns 0 on success, -1 on error.
-export fn gossamer_load_panel(handle: WindowHandle, uri: [*c]const u8) callconv(.C) i32 {
+export fn gossamer_load_panel(handle: WindowHandle, uri: [*c]const u8) i32 {
     if (handle == 0 or uri == null) return -1;
     return 0;
 }
 
 /// Evaluate JavaScript in a window context. Returns 0 on success.
-export fn gossamer_eval_js(handle: WindowHandle, script: [*c]const u8) callconv(.C) i32 {
+export fn gossamer_eval_js(handle: WindowHandle, script: [*c]const u8) i32 {
     if (handle == 0 or script == null) return -1;
     return 0;
 }
 
 /// Get runtime version. Returns packed major.minor.patch.
-export fn gossamer_get_version() callconv(.C) u32 {
+export fn gossamer_get_version() u32 {
     return (0 << 16) | (1 << 8) | 0; // 0.1.0
 }
 

cartridges/hypatia-mcp/ffi/hypatia_ffi.zig

@@ -6,25 +6,25 @@
 const std = @import("std");
 
 /// Scan a repository path. Returns scan ID or 0 on failure.
-export fn hypatia_scan_repo(path: [*c]const u8) callconv(.C) u32 {
+export fn hypatia_scan_repo(path: [*c]const u8) u32 {
     if (path == null) return 0;
     return 1; // Stub
 }
 
 /// Begin model training. Returns 0 on success.
-export fn hypatia_train_model(model_name: [*c]const u8) callconv(.C) i32 {
+export fn hypatia_train_model(model_name: [*c]const u8) i32 {
     if (model_name == null) return -1;
     return 0; // Stub
 }
 
 /// Get the score for a completed scan (0-100).
-export fn hypatia_get_score(scan_id: u32) callconv(.C) u8 {
+export fn hypatia_get_score(scan_id: u32) u8 {
     if (scan_id == 0) return 0;
     return 85; // Stub
 }
 
 /// Get active rule count.
-export fn hypatia_get_rule_count() callconv(.C) u32 {
+export fn hypatia_get_rule_count() u32 {
     return 17; // Stub — matches standard workflow set
 }