getsentry · dcramer · May 9, 2026
diff --git a/AGENTS.md b/AGENTS.md
@@ -79,6 +79,7 @@ Co-Authored-By: (agent model name) <email>
 - Do not add mutable runtime behavior globals or test-only singleton mutation APIs (`set*ForTests`, `reset*ForTests`, observer globals for core behavior).
 - Prefer small consumer-owned service interfaces over broad deps bags or service locators.
 - Do not leak third-party SDK types across chat subsystem boundaries when a small local interface will do; keep vendor SDKs inside infrastructure modules.
+- Service modules must depend on small injected ports for Slack behavior, not import Slack infrastructure directly.
 - `runtime/` orchestrates turns and turn-scoped formatting, `services/` do domain work (reply policy, delivery planning, channel intent, attachment validation), `state/` persists by concern, `ingress/` only normalizes/routes.
 - **Feature-based colocation**: group files by domain feature, not by technical role. Within a module, create subdirectories for each feature domain (e.g., `tools/slack/`, `tools/web/`, `tools/sandbox/`, `tools/skill/`). Shared contracts and cross-cutting utilities live at the module root. Only extract to a shared location when 2+ features need the same code.
 - Do not use barrel `index.ts` re-exports inside feature subdirectories — import directly from the source file. A module-root `index.ts` is acceptable as a composition root that wires features together.

diff --git a/packages/junior/.dependency-cruiser.mjs b/packages/junior/.dependency-cruiser.mjs
@@ -24,6 +24,18 @@ export default {
         path: "^src/chat/runtime/",
       },
     },
+    {
+      name: "no-chat-services-to-slack",
+      comment:
+        "Service modules must depend on small injected ports, not Slack infrastructure.",
+      severity: "error",
+      from: {
+        path: "^src/chat/services/",
+      },
+      to: {
+        path: "^src/chat/slack/",
+      },
+    },
     {
       name: "no-chat-state-to-runtime",
       comment: "State modules must not depend on runtime orchestration.",

diff --git a/packages/junior/src/chat/app/services.ts b/packages/junior/src/chat/app/services.ts
@@ -45,9 +45,8 @@ export function createJuniorRuntimeServices(
     completeText: overrides.visionContext?.completeText ?? completeText,
     listThreadReplies:
       overrides.visionContext?.listThreadReplies ?? listThreadReplies,
-    downloadPrivateSlackFile:
-      overrides.visionContext?.downloadPrivateSlackFile ??
-      downloadPrivateSlackFile,
+    downloadFile:
+      overrides.visionContext?.downloadFile ?? downloadPrivateSlackFile,
   });
 
   return {

diff --git a/packages/junior/src/chat/runtime/reply-executor.ts b/packages/junior/src/chat/runtime/reply-executor.ts
@@ -35,7 +35,7 @@ import {
 import { completeAuthPauseTurn } from "@/chat/runtime/auth-pause-state";
 import type { PreparedTurnState } from "@/chat/runtime/turn-preparation";
 import {
-  generateThreadTitle,
+  type ConversationMemoryService,
   markConversationMessage,
   normalizeConversationText,
   upsertConversationMessage,
@@ -68,7 +68,7 @@ import {
 
 export interface ReplyExecutorServices {
   generateAssistantReply: typeof generateAssistantReplyImpl;
-  generateThreadTitle: typeof generateThreadTitle;
+  generateThreadTitle: ConversationMemoryService["generateThreadTitle"];
   lookupSlackUser: typeof lookupSlackUser;
   scheduleTurnTimeoutResume: (
     request: TurnTimeoutResumeRequest,

diff --git a/packages/junior/src/chat/runtime/turn-preparation.ts b/packages/junior/src/chat/runtime/turn-preparation.ts
@@ -13,22 +13,22 @@ import {
   type ThreadArtifactsState,
 } from "@/chat/state/artifacts";
 import {
-  compactConversationIfNeeded,
   buildConversationContext,
   isHumanConversationMessage,
   normalizeConversationText,
-  seedConversationBackfill,
+  updateConversationStats,
   upsertConversationMessage,
 } from "@/chat/services/conversation-memory";
 import {
   countPotentialImageAttachments,
   hasPotentialImageAttachment,
-  hydrateConversationVisionContext,
   isVisionEnabled,
 } from "@/chat/services/vision-context";
 import { getChannelConfigurationService } from "@/chat/runtime/thread-state";
 import type { ChannelConfigurationService } from "@/chat/configuration/types";
 
+const BACKFILL_MESSAGE_LIMIT = 80;
+
 export interface PreparedTurnState {
   artifacts: ThreadArtifactsState;
   configuration?: Record<string, unknown>;
@@ -42,8 +42,25 @@ export interface PreparedTurnState {
 }
 
 export interface PrepareTurnStateDeps {
-  compactConversationIfNeeded: typeof compactConversationIfNeeded;
-  hydrateConversationVisionContext: typeof hydrateConversationVisionContext;
+  compactConversationIfNeeded: (
+    conversation: ThreadConversationState,
+    context: {
+      threadId?: string;
+      channelId?: string;
+      requesterId?: string;
+      runId?: string;
+    },
+  ) => Promise<void>;
+  hydrateConversationVisionContext: (
+    conversation: ThreadConversationState,
+    context: {
+      threadId?: string;
+      channelId?: string;
+      requesterId?: string;
+      runId?: string;
+      threadTs?: string;
+    },
+  ) => Promise<void>;
 }
 
 function hasPendingImageHydration(
@@ -55,6 +72,117 @@ function hasPendingImageHydration(
   );
 }
 
+function createConversationMessageFromSdkMessage(
+  entry: Message,
+): ConversationMessage | null {
+  const rawText = normalizeConversationText(entry.text);
+  if (!rawText) {
+    return null;
+  }
+
+  return {
+    id: entry.id,
+    role: entry.author.isMe ? "assistant" : "user",
+    text: rawText,
+    createdAtMs: entry.metadata.dateSent.getTime(),
+    author: {
+      userId: entry.author.userId,
+      userName: entry.author.userName,
+      fullName: entry.author.fullName,
+      isBot:
+        typeof entry.author.isBot === "boolean"
+          ? entry.author.isBot
+          : undefined,
+    },
+    meta: {
+      slackTs: getSlackMessageTs(entry),
+    },
+  };
+}
+
+async function seedConversationBackfill(
+  thread: Thread,
+  conversation: ThreadConversationState,
+  currentTurn: {
+    messageId: string;
+    messageCreatedAtMs: number;
+  },
+): Promise<void> {
+  if (conversation.backfill.completedAtMs) {
+    return;
+  }
+  if (conversation.messages.length > 0 || conversation.compactions.length > 0) {
+    conversation.backfill = {
+      completedAtMs: Date.now(),
+      source: "recent_messages",
+    };
+    updateConversationStats(conversation);
+    return;
+  }
+
+  const seeded: ConversationMessage[] = [];
+  let source: "recent_messages" | "thread_fetch" = "recent_messages";
+
+  try {
+    const fetchedNewestFirst: Message[] = [];
+    for await (const entry of thread.messages) {
+      fetchedNewestFirst.push(entry);
+      if (fetchedNewestFirst.length >= BACKFILL_MESSAGE_LIMIT) {
+        break;
+      }
+    }
+    fetchedNewestFirst.reverse();
+    for (const entry of fetchedNewestFirst) {
+      const message = createConversationMessageFromSdkMessage(entry);
+      if (message) {
+        seeded.push(message);
+      }
+    }
+    if (seeded.length > 0) {
+      source = "thread_fetch";
+    }
+  } catch {}
+
+  if (seeded.length === 0) {
+    try {
+      await thread.refresh();
+    } catch {}
+
+    const fromRecent = thread.recentMessages.slice(-BACKFILL_MESSAGE_LIMIT);
+    for (const entry of fromRecent) {
+      const message = createConversationMessageFromSdkMessage(entry);
+      if (message) {
+        seeded.push(message);
+      }
+    }
+    source = "recent_messages";
+  }
+
+  for (const message of seeded) {
+    if (
+      message.id !== currentTurn.messageId &&
+      message.createdAtMs > currentTurn.messageCreatedAtMs
+    ) {
+      continue;
+    }
+    if (
+      message.id !== currentTurn.messageId &&
+      message.createdAtMs === currentTurn.messageCreatedAtMs &&
+      message.id > currentTurn.messageId
+    ) {
+      continue;
+    }
+    upsertConversationMessage(conversation, message);
+  }
+
+  conversation.backfill = {
+    completedAtMs: Date.now(),
+    source,
+  };
+  updateConversationStats(conversation);
+}
+
+/** Build the turn-state preparer from injected conversation services. */
 export function createPrepareTurnState(deps: PrepareTurnStateDeps) {
   return async function prepareTurnState(args: {
     explicitMention: boolean;

diff --git a/packages/junior/src/chat/services/conversation-memory.ts b/packages/junior/src/chat/services/conversation-memory.ts
@@ -1,7 +1,5 @@
-import type { Message, Thread } from "chat";
 import { botConfig } from "@/chat/config";
-import { completeText } from "@/chat/pi/client";
-import { getSlackMessageTs } from "@/chat/slack/message";
+import type { completeText } from "@/chat/pi/client";
 import type {
   ConversationCompaction,
   ConversationMessage,
@@ -17,7 +15,6 @@ const CONTEXT_MIN_LIVE_MESSAGES = 12;
 const CONTEXT_COMPACTION_BATCH_SIZE = 24;
 const CONTEXT_MAX_COMPACTIONS = 16;
 const CONTEXT_MAX_MESSAGE_CHARS = 3200;
-const BACKFILL_MESSAGE_LIMIT = 80;
 
 export interface ConversationMemoryDeps {
   completeText: typeof completeText;
@@ -417,6 +414,7 @@ async function compactConversationIfNeededWithDeps(
   }
 }
 
+/** Build the service that owns durable conversation memory compaction and titles. */
 export function createConversationMemoryService(
   deps: ConversationMemoryDeps,
 ): ConversationMemoryService {
@@ -428,125 +426,6 @@ export function createConversationMemoryService(
   };
 }
 
-const defaultConversationMemoryService = createConversationMemoryService({
-  completeText,
-});
-
-export const compactConversationIfNeeded =
-  defaultConversationMemoryService.compactConversationIfNeeded;
-export const generateThreadTitle =
-  defaultConversationMemoryService.generateThreadTitle;
-
-function createConversationMessageFromSdkMessage(
-  entry: Message,
-): ConversationMessage | null {
-  const rawText = normalizeConversationText(entry.text);
-  if (!rawText) {
-    return null;
-  }
-
-  return {
-    id: entry.id,
-    role: entry.author.isMe ? "assistant" : "user",
-    text: rawText,
-    createdAtMs: entry.metadata.dateSent.getTime(),
-    author: {
-      userId: entry.author.userId,
-      userName: entry.author.userName,
-      fullName: entry.author.fullName,
-      isBot:
-        typeof entry.author.isBot === "boolean"
-          ? entry.author.isBot
-          : undefined,
-    },
-    meta: {
-      slackTs: getSlackMessageTs(entry),
-    },
-  };
-}
-
-export async function seedConversationBackfill(
-  thread: Thread,
-  conversation: ThreadConversationState,
-  currentTurn: {
-    messageId: string;
-    messageCreatedAtMs: number;
-  },
-): Promise<void> {
-  if (conversation.backfill.completedAtMs) {
-    return;
-  }
-  if (conversation.messages.length > 0 || conversation.compactions.length > 0) {
-    conversation.backfill = {
-      completedAtMs: Date.now(),
-      source: "recent_messages",
-    };
-    updateConversationStats(conversation);
-    return;
-  }
-
-  const seeded: ConversationMessage[] = [];
-  let source: "recent_messages" | "thread_fetch" = "recent_messages";
-
-  try {
-    const fetchedNewestFirst: Message[] = [];
-    for await (const entry of thread.messages) {
-      fetchedNewestFirst.push(entry);
-      if (fetchedNewestFirst.length >= BACKFILL_MESSAGE_LIMIT) {
-        break;
-      }
-    }
-    fetchedNewestFirst.reverse();
-    for (const entry of fetchedNewestFirst) {
-      const message = createConversationMessageFromSdkMessage(entry);
-      if (message) {
-        seeded.push(message);
-      }
-    }
-    if (seeded.length > 0) {
-      source = "thread_fetch";
-    }
-  } catch {}
-
-  if (seeded.length === 0) {
-    try {
-      await thread.refresh();
-    } catch {}
-
-    const fromRecent = thread.recentMessages.slice(-BACKFILL_MESSAGE_LIMIT);
-    for (const entry of fromRecent) {
-      const message = createConversationMessageFromSdkMessage(entry);
-      if (message) {
-        seeded.push(message);
-      }
-    }
-    source = "recent_messages";
-  }
-
-  for (const message of seeded) {
-    if (
-      message.id !== currentTurn.messageId &&
-      message.createdAtMs > currentTurn.messageCreatedAtMs
-    ) {
-      continue;
-    }
-    if (
-      message.id !== currentTurn.messageId &&
-      message.createdAtMs === currentTurn.messageCreatedAtMs &&
-      message.id > currentTurn.messageId
-    ) {
-      continue;
-    }
-    upsertConversationMessage(conversation, message);
-  }
-
-  conversation.backfill = {
-    completedAtMs: Date.now(),
-    source,
-  };
-  updateConversationStats(conversation);
-}
-
 export function isHumanConversationMessage(
   message: ConversationMessage,
 ): boolean {