transcript gutter

CHANGELOG.md

@@ -1,12 +1,5 @@
 # Changelog
 
-## [0.28.0](https://github.com/Monadical-SAS/reflector/compare/v0.27.0...v0.28.0) (2026-01-20)
-
-
-### Features
-
-* worker affinity ([#819](https://github.com/Monadical-SAS/reflector/issues/819)) ([3b6540e](https://github.com/Monadical-SAS/reflector/commit/3b6540eae5b597449f98661bdf15483b77be3268))
-
 ## [0.27.0](https://github.com/Monadical-SAS/reflector/compare/v0.26.0...v0.27.0) (2025-12-26)
 
 

docker-compose.yml

@@ -34,7 +34,7 @@ services:
     environment:
       ENTRYPOINT: beat
 
-  hatchet-worker-cpu:
+  hatchet-worker:
     build:
       context: server
     volumes:
@@ -43,20 +43,7 @@ services:
     env_file:
       - ./server/.env
     environment:
-      ENTRYPOINT: hatchet-worker-cpu
-    depends_on:
-      hatchet:
-        condition: service_healthy
-  hatchet-worker-llm:
-    build:
-      context: server
-    volumes:
-      - ./server/:/app/
-      - /app/.venv
-    env_file:
-      - ./server/.env
-    environment:
-      ENTRYPOINT: hatchet-worker-llm
+      ENTRYPOINT: hatchet-worker
     depends_on:
       hatchet:
         condition: service_healthy

gpu/modal_deployments/deploy-all.sh

@@ -131,15 +131,6 @@ if [ -z "$DIARIZER_URL" ]; then
 fi
 echo "  -> $DIARIZER_URL"
 
-echo ""
-echo "Deploying mixdown (CPU audio processing)..."
-MIXDOWN_URL=$(modal deploy reflector_mixdown.py 2>&1 | grep -o 'https://[^ ]*web.modal.run' | head -1)
-if [ -z "$MIXDOWN_URL" ]; then
-    echo "Error: Failed to deploy mixdown. Check Modal dashboard for details."
-    exit 1
-fi
-echo "  -> $MIXDOWN_URL"
-
 # --- Output Configuration ---
 echo ""
 echo "=========================================="
@@ -156,8 +147,4 @@ echo ""
 echo "DIARIZATION_BACKEND=modal"
 echo "DIARIZATION_URL=$DIARIZER_URL"
 echo "DIARIZATION_MODAL_API_KEY=$API_KEY"
-echo ""
-echo "MIXDOWN_BACKEND=modal"
-echo "MIXDOWN_URL=$MIXDOWN_URL"
-echo "MIXDOWN_MODAL_API_KEY=$API_KEY"
 echo "# --- End Modal Configuration ---"

gpu/modal_deployments/reflector_mixdown.py

@@ -1,379 +0,0 @@
-"""
-Reflector GPU backend - audio mixdown
-======================================
-
-CPU-intensive audio mixdown service for combining multiple audio tracks.
-Uses PyAV filter graph (amix) for high-quality audio mixing.
-"""
-
-import os
-import tempfile
-import time
-from fractions import Fraction
-
-import modal
-
-MIXDOWN_TIMEOUT = 900  # 15 minutes
-SCALEDOWN_WINDOW = 60  # 1 minute idle before shutdown
-
-app = modal.App("reflector-mixdown")
-
-# CPU-based image (no GPU needed for audio processing)
-image = (
-    modal.Image.debian_slim(python_version="3.12")
-    .apt_install("ffmpeg")  # Required by PyAV
-    .pip_install(
-        "av==13.1.0",  # PyAV for audio processing
-        "requests==2.32.3",  # HTTP for presigned URL downloads/uploads
-        "fastapi==0.115.12",  # API framework
-    )
-)
-
-
-@app.function(
-    cpu=4.0,  # 4 CPU cores for audio processing
-    timeout=MIXDOWN_TIMEOUT,
-    scaledown_window=SCALEDOWN_WINDOW,
-    secrets=[modal.Secret.from_name("reflector-gpu")],
-    image=image,
-)
-@modal.concurrent(max_inputs=10)
-@modal.asgi_app()
-def web():
-    import logging
-    import secrets
-    import shutil
-
-    import av
-    import requests
-    from av.audio.resampler import AudioResampler
-    from fastapi import Depends, FastAPI, HTTPException, status
-    from fastapi.security import OAuth2PasswordBearer
-    from pydantic import BaseModel
-
-    # Setup logging
-    logging.basicConfig(
-        level=logging.INFO, format="%(asctime)s - %(levelname)s - %(message)s"
-    )
-    logger = logging.getLogger(__name__)
-
-    app = FastAPI()
-    oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")
-
-    # Validate API key exists at startup
-    API_KEY = os.environ.get("REFLECTOR_GPU_APIKEY")
-    if not API_KEY:
-        raise RuntimeError("REFLECTOR_GPU_APIKEY not configured in Modal secrets")
-
-    def apikey_auth(apikey: str = Depends(oauth2_scheme)):
-        # Use constant-time comparison to prevent timing attacks
-        if secrets.compare_digest(apikey, API_KEY):
-            return
-        raise HTTPException(
-            status_code=status.HTTP_401_UNAUTHORIZED,
-            detail="Invalid API key",
-            headers={"WWW-Authenticate": "Bearer"},
-        )
-
-    class MixdownRequest(BaseModel):
-        track_urls: list[str]
-        output_url: str
-        target_sample_rate: int = 48000
-        expected_duration_sec: float | None = None
-
-    class MixdownResponse(BaseModel):
-        duration_ms: float
-        tracks_mixed: int
-        audio_uploaded: bool
-
-    def download_track(url: str, temp_dir: str, index: int) -> str:
-        """Download track from presigned URL to temp file using streaming."""
-        logger.info(f"Downloading track {index + 1}")
-        response = requests.get(url, stream=True, timeout=300)
-
-        if response.status_code == 404:
-            raise HTTPException(status_code=404, detail=f"Track {index} not found")
-        if response.status_code == 403:
-            raise HTTPException(
-                status_code=403, detail=f"Track {index} presigned URL expired"
-            )
-
-        response.raise_for_status()
-
-        temp_path = os.path.join(temp_dir, f"track_{index}.webm")
-        total_bytes = 0
-        with open(temp_path, "wb") as f:
-            for chunk in response.iter_content(chunk_size=8192):
-                if chunk:
-                    f.write(chunk)
-                    total_bytes += len(chunk)
-
-        logger.info(f"Track {index + 1} downloaded: {total_bytes} bytes")
-        return temp_path
-
-    def mixdown_tracks_modal(
-        track_paths: list[str],
-        output_path: str,
-        target_sample_rate: int,
-        expected_duration_sec: float | None,
-        logger,
-    ) -> float:
-        """Mix multiple audio tracks using PyAV filter graph.
-
-        Args:
-            track_paths: List of local file paths to audio tracks
-            output_path: Local path for output MP3 file
-            target_sample_rate: Sample rate for output (Hz)
-            expected_duration_sec: Optional fallback duration if container metadata unavailable
-            logger: Logger instance for progress tracking
-
-        Returns:
-            Duration in milliseconds
-        """
-        logger.info(f"Starting mixdown of {len(track_paths)} tracks")
-
-        # Build PyAV filter graph: N abuffer -> amix -> aformat -> sink
-        graph = av.filter.Graph()
-        inputs = []
-
-        for idx in range(len(track_paths)):
-            args = (
-                f"time_base=1/{target_sample_rate}:"
-                f"sample_rate={target_sample_rate}:"
-                f"sample_fmt=s32:"
-                f"channel_layout=stereo"
-            )
-            in_ctx = graph.add("abuffer", args=args, name=f"in{idx}")
-            inputs.append(in_ctx)
-
-        mixer = graph.add("amix", args=f"inputs={len(inputs)}:normalize=0", name="mix")
-        fmt = graph.add(
-            "aformat",
-            args=f"sample_fmts=s32:channel_layouts=stereo:sample_rates={target_sample_rate}",
-            name="fmt",
-        )
-        sink = graph.add("abuffersink", name="out")
-
-        # Connect inputs to mixer (no delays for Modal implementation)
-        for idx, in_ctx in enumerate(inputs):
-            in_ctx.link_to(mixer, 0, idx)
-
-        mixer.link_to(fmt)
-        fmt.link_to(sink)
-        graph.configure()
-
-        # Open all containers
-        containers = []
-        try:
-            for i, path in enumerate(track_paths):
-                try:
-                    c = av.open(path)
-                    containers.append(c)
-                except Exception as e:
-                    logger.warning(
-                        f"Failed to open container {i}: {e}",
-                    )
-
-            if not containers:
-                raise ValueError("Could not open any track containers")
-
-            # Calculate total duration for progress reporting
-            max_duration_sec = 0.0
-            for c in containers:
-                if c.duration is not None:
-                    dur_sec = c.duration / av.time_base
-                    max_duration_sec = max(max_duration_sec, dur_sec)
-            if max_duration_sec == 0.0 and expected_duration_sec:
-                max_duration_sec = expected_duration_sec
-
-            # Setup output container
-            out_container = av.open(output_path, "w", format="mp3")
-            out_stream = out_container.add_stream("libmp3lame", rate=target_sample_rate)
-
-            decoders = [c.decode(audio=0) for c in containers]
-            active = [True] * len(decoders)
-            resamplers = [
-                AudioResampler(format="s32", layout="stereo", rate=target_sample_rate)
-                for _ in decoders
-            ]
-
-            current_max_time = 0.0
-            last_log_time = time.monotonic()
-            start_time = time.monotonic()
-
-            total_duration = 0
-
-            while any(active):
-                for i, (dec, is_active) in enumerate(zip(decoders, active)):
-                    if not is_active:
-                        continue
-                    try:
-                        frame = next(dec)
-                    except StopIteration:
-                        active[i] = False
-                        inputs[i].push(None)  # Signal end of stream
-                        continue
-
-                    if frame.sample_rate != target_sample_rate:
-                        continue
-
-                    # Progress logging (every 5 seconds)
-                    if frame.time is not None:
-                        current_max_time = max(current_max_time, frame.time)
-                        now = time.monotonic()
-                        if now - last_log_time >= 5.0:
-                            elapsed = now - start_time
-                            if max_duration_sec > 0:
-                                progress_pct = min(
-                                    100.0, (current_max_time / max_duration_sec) * 100
-                                )
-                                logger.info(
-                                    f"Mixdown progress: {progress_pct:.1f}% @ {current_max_time:.1f}s (elapsed: {elapsed:.1f}s)"
-                                )
-                            else:
-                                logger.info(
-                                    f"Mixdown progress: @ {current_max_time:.1f}s (elapsed: {elapsed:.1f}s)"
-                                )
-                            last_log_time = now
-
-                    out_frames = resamplers[i].resample(frame) or []
-                    for rf in out_frames:
-                        rf.sample_rate = target_sample_rate
-                        rf.time_base = Fraction(1, target_sample_rate)
-                        inputs[i].push(rf)
-
-                    # Pull mixed frames from sink and encode
-                    while True:
-                        try:
-                            mixed = sink.pull()
-                        except Exception:
-                            break
-                        mixed.sample_rate = target_sample_rate
-                        mixed.time_base = Fraction(1, target_sample_rate)
-
-                        # Encode and mux
-                        for packet in out_stream.encode(mixed):
-                            out_container.mux(packet)
-                            total_duration += packet.duration
-
-            # Flush remaining frames from filter graph
-            while True:
-                try:
-                    mixed = sink.pull()
-                except Exception:
-                    break
-                mixed.sample_rate = target_sample_rate
-                mixed.time_base = Fraction(1, target_sample_rate)
-
-                for packet in out_stream.encode(mixed):
-                    out_container.mux(packet)
-                    total_duration += packet.duration
-
-            # Flush encoder
-            for packet in out_stream.encode():
-                out_container.mux(packet)
-                total_duration += packet.duration
-
-            # Calculate duration in milliseconds
-            if total_duration > 0:
-                # Use the same calculation as AudioFileWriterProcessor
-                duration_ms = round(
-                    float(total_duration * out_stream.time_base * 1000), 2
-                )
-            else:
-                duration_ms = 0.0
-
-            out_container.close()
-            logger.info(f"Mixdown complete: duration={duration_ms}ms")
-
-        finally:
-            # Cleanup all containers
-            for c in containers:
-                if c is not None:
-                    try:
-                        c.close()
-                    except Exception:
-                        pass
-
-        return duration_ms
-
-    @app.post("/v1/audio/mixdown", dependencies=[Depends(apikey_auth)])
-    def mixdown(request: MixdownRequest) -> MixdownResponse:
-        """Mix multiple audio tracks into a single MP3 file.
-
-        Tracks are downloaded from presigned S3 URLs, mixed using PyAV,
-        and uploaded to a presigned S3 PUT URL.
-        """
-        if not request.track_urls:
-            raise HTTPException(status_code=400, detail="No track URLs provided")
-
-        logger.info(f"Mixdown request: {len(request.track_urls)} tracks")
-
-        temp_dir = tempfile.mkdtemp()
-        temp_files = []
-        output_mp3_path = None
-
-        try:
-            # Download all tracks
-            for i, url in enumerate(request.track_urls):
-                temp_path = download_track(url, temp_dir, i)
-                temp_files.append(temp_path)
-
-            # Mix tracks
-            output_mp3_path = os.path.join(temp_dir, "mixed.mp3")
-            duration_ms = mixdown_tracks_modal(
-                temp_files,
-                output_mp3_path,
-                request.target_sample_rate,
-                request.expected_duration_sec,
-                logger,
-            )
-
-            # Upload result to S3
-            logger.info("Uploading result to S3")
-            file_size = os.path.getsize(output_mp3_path)
-            with open(output_mp3_path, "rb") as f:
-                upload_response = requests.put(
-                    request.output_url, data=f, timeout=300
-                )
-
-            if upload_response.status_code == 403:
-                raise HTTPException(
-                    status_code=403, detail="Output presigned URL expired"
-                )
-
-            upload_response.raise_for_status()
-            logger.info(f"Upload complete: {file_size} bytes")
-
-            return MixdownResponse(
-                duration_ms=duration_ms,
-                tracks_mixed=len(request.track_urls),
-                audio_uploaded=True,
-            )
-
-        except HTTPException:
-            raise
-        except Exception as e:
-            logger.error(f"Mixdown failed: {e}", exc_info=True)
-            raise HTTPException(status_code=500, detail=f"Mixdown failed: {str(e)}")
-
-        finally:
-            # Cleanup temp files
-            for temp_path in temp_files:
-                try:
-                    os.unlink(temp_path)
-                except Exception as e:
-                    logger.warning(f"Failed to cleanup temp file {temp_path}: {e}")
-
-            if output_mp3_path and os.path.exists(output_mp3_path):
-                try:
-                    os.unlink(output_mp3_path)
-                except Exception as e:
-                    logger.warning(f"Failed to cleanup output file {output_mp3_path}: {e}")
-
-            try:
-                shutil.rmtree(temp_dir)
-            except Exception as e:
-                logger.warning(f"Failed to cleanup temp directory {temp_dir}: {e}")
-
-    return app

server/reflector/hatchet/run_workers.py

@@ -0,0 +1,77 @@
+"""
+Run Hatchet workers for the multitrack pipeline.
+Runs as a separate process, just like Celery workers.
+
+Usage:
+    uv run -m reflector.hatchet.run_workers
+
+    # Or via docker:
+    docker compose exec server uv run -m reflector.hatchet.run_workers
+"""
+
+import signal
+import sys
+
+from hatchet_sdk.rate_limit import RateLimitDuration
+
+from reflector.hatchet.constants import LLM_RATE_LIMIT_KEY, LLM_RATE_LIMIT_PER_SECOND
+from reflector.logger import logger
+from reflector.settings import settings
+
+
+def main() -> None:
+    """Start Hatchet worker polling."""
+    if not settings.HATCHET_ENABLED:
+        logger.error("HATCHET_ENABLED is False, not starting workers")
+        sys.exit(1)
+
+    if not settings.HATCHET_CLIENT_TOKEN:
+        logger.error("HATCHET_CLIENT_TOKEN is not set")
+        sys.exit(1)
+
+    logger.info(
+        "Starting Hatchet workers",
+        debug=settings.HATCHET_DEBUG,
+    )
+
+    # Import here (not top-level) - workflow modules call HatchetClientManager.get_client()
+    # at module level because Hatchet SDK decorators (@workflow.task) bind at import time.
+    # Can't use lazy init: decorators need the client object when function is defined.
+    from reflector.hatchet.client import HatchetClientManager  # noqa: PLC0415
+    from reflector.hatchet.workflows import (  # noqa: PLC0415
+        daily_multitrack_pipeline,
+        subject_workflow,
+        topic_chunk_workflow,
+        track_workflow,
+    )
+
+    hatchet = HatchetClientManager.get_client()
+
+    hatchet.rate_limits.put(
+        LLM_RATE_LIMIT_KEY, LLM_RATE_LIMIT_PER_SECOND, RateLimitDuration.SECOND
+    )
+
+    worker = hatchet.worker(
+        "reflector-pipeline-worker",
+        workflows=[
+            daily_multitrack_pipeline,
+            subject_workflow,
+            topic_chunk_workflow,
+            track_workflow,
+        ],
+    )
+
+    def shutdown_handler(signum: int, frame) -> None:
+        logger.info("Received shutdown signal, stopping workers...")
+        # Worker cleanup happens automatically on exit
+        sys.exit(0)
+
+    signal.signal(signal.SIGINT, shutdown_handler)
+    signal.signal(signal.SIGTERM, shutdown_handler)
+
+    logger.info("Starting Hatchet worker polling...")
+    worker.start()
+
+
+if __name__ == "__main__":
+    main()

server/reflector/hatchet/run_workers_cpu.py

@@ -1,48 +0,0 @@
-"""
-CPU-heavy worker pool for audio processing tasks.
-Handles ONLY: mixdown_tracks
-
-Configuration:
-- slots=1: Only mixdown (already serialized globally with max_runs=1)
-- Worker affinity: pool=cpu-heavy
-"""
-
-from reflector.hatchet.client import HatchetClientManager
-from reflector.hatchet.workflows.daily_multitrack_pipeline import (
-    daily_multitrack_pipeline,
-)
-from reflector.logger import logger
-from reflector.settings import settings
-
-
-def main():
-    if not settings.HATCHET_ENABLED:
-        logger.error("HATCHET_ENABLED is False, not starting CPU workers")
-        return
-
-    hatchet = HatchetClientManager.get_client()
-
-    logger.info(
-        "Starting Hatchet CPU worker pool (mixdown only)",
-        worker_name="cpu-worker-pool",
-        slots=1,
-        labels={"pool": "cpu-heavy"},
-    )
-
-    cpu_worker = hatchet.worker(
-        "cpu-worker-pool",
-        slots=1,  # Only 1 mixdown at a time (already serialized globally)
-        labels={
-            "pool": "cpu-heavy",
-        },
-        workflows=[daily_multitrack_pipeline],
-    )
-
-    try:
-        cpu_worker.start()
-    except KeyboardInterrupt:
-        logger.info("Received shutdown signal, stopping CPU workers...")
-
-
-if __name__ == "__main__":
-    main()

server/reflector/hatchet/run_workers_llm.py

@@ -1,56 +0,0 @@
-"""
-LLM/I/O worker pool for all non-CPU tasks.
-Handles: all tasks except mixdown_tracks (transcription, LLM inference, orchestration)
-"""
-
-from reflector.hatchet.client import HatchetClientManager
-from reflector.hatchet.workflows.daily_multitrack_pipeline import (
-    daily_multitrack_pipeline,
-)
-from reflector.hatchet.workflows.subject_processing import subject_workflow
-from reflector.hatchet.workflows.topic_chunk_processing import topic_chunk_workflow
-from reflector.hatchet.workflows.track_processing import track_workflow
-from reflector.logger import logger
-from reflector.settings import settings
-
-SLOTS = 10
-WORKER_NAME = "llm-worker-pool"
-POOL = "llm-io"
-
-
-def main():
-    if not settings.HATCHET_ENABLED:
-        logger.error("HATCHET_ENABLED is False, not starting LLM workers")
-        return
-
-    hatchet = HatchetClientManager.get_client()
-
-    logger.info(
-        "Starting Hatchet LLM worker pool (all tasks except mixdown)",
-        worker_name=WORKER_NAME,
-        slots=SLOTS,
-        labels={"pool": POOL},
-    )
-
-    llm_worker = hatchet.worker(
-        WORKER_NAME,
-        slots=SLOTS,  # not all slots are probably used
-        labels={
-            "pool": POOL,
-        },
-        workflows=[
-            daily_multitrack_pipeline,
-            topic_chunk_workflow,
-            subject_workflow,
-            track_workflow,
-        ],
-    )
-
-    try:
-        llm_worker.start()
-    except KeyboardInterrupt:
-        logger.info("Received shutdown signal, stopping LLM workers...")
-
-
-if __name__ == "__main__":
-    main()

server/reflector/hatchet/workflows/daily_multitrack_pipeline.py

@@ -23,12 +23,7 @@ from pathlib import Path
 from typing import Any, Callable, Coroutine, Protocol, TypeVar
 
 import httpx
-from hatchet_sdk import (
-    ConcurrencyExpression,
-    ConcurrencyLimitStrategy,
-    Context,
-)
-from hatchet_sdk.labels import DesiredWorkerLabel
+from hatchet_sdk import Context
 from pydantic import BaseModel
 
 from reflector.dailyco_api.client import DailyApiClient
@@ -472,24 +467,10 @@ async def process_tracks(input: PipelineInput, ctx: Context) -> ProcessTracksRes
     parents=[process_tracks],
     execution_timeout=timedelta(seconds=TIMEOUT_AUDIO),
     retries=3,
-    desired_worker_labels={
-        "pool": DesiredWorkerLabel(
-            value="cpu-heavy",
-            required=True,
-            weight=100,
-        ),
-    },
-    concurrency=[
-        ConcurrencyExpression(
-            expression="'mixdown-global'",
-            max_runs=1,  # serialize mixdown to prevent resource contention
-            limit_strategy=ConcurrencyLimitStrategy.GROUP_ROUND_ROBIN,  # Queue
-        )
-    ],
 )
 @with_error_handling(TaskName.MIXDOWN_TRACKS)
 async def mixdown_tracks(input: PipelineInput, ctx: Context) -> MixdownResult:
-    """Mix all padded tracks into single audio file using PyAV or Modal backend."""
+    """Mix all padded tracks into single audio file using PyAV (same as Celery)."""
     ctx.log("mixdown_tracks: mixing padded tracks into single audio file")
 
     track_result = ctx.task_output(process_tracks)
@@ -513,7 +494,7 @@ async def mixdown_tracks(input: PipelineInput, ctx: Context) -> MixdownResult:
 
     storage = _spawn_storage()
 
-    # Presign URLs for padded tracks (same expiration for both backends)
+    # Presign URLs on demand (avoids stale URLs on workflow replay)
     padded_urls = []
     for track_info in padded_tracks:
         if track_info.key:
@@ -534,79 +515,13 @@ async def mixdown_tracks(input: PipelineInput, ctx: Context) -> MixdownResult:
         logger.error("Mixdown failed - no decodable audio frames found")
         raise ValueError("No decodable audio frames in any track")
 
-    output_key = f"{input.transcript_id}/audio.mp3"
-
-    # Conditional: Modal or local backend
-    if settings.MIXDOWN_BACKEND == "modal":
-        ctx.log("mixdown_tracks: using Modal backend")
-
-        # Presign PUT URL for output (Modal will upload directly)
-        output_url = await storage.get_file_url(
-            output_key,
-            operation="put_object",
-            expires_in=PRESIGNED_URL_EXPIRATION_SECONDS,
-        )
-
-        from reflector.processors.audio_mixdown_modal import (  # noqa: PLC0415
-            AudioMixdownModalProcessor,
-        )
-
-        try:
-            processor = AudioMixdownModalProcessor()
-            result = await processor.mixdown(
-                track_urls=valid_urls,
-                output_url=output_url,
-                target_sample_rate=target_sample_rate,
-                expected_duration_sec=recording_duration
-                if recording_duration > 0
-                else None,
-            )
-            duration_ms = result.duration_ms
-            tracks_mixed = result.tracks_mixed
-
-            ctx.log(
-                f"mixdown_tracks: Modal returned duration={duration_ms}ms, tracks={tracks_mixed}"
-            )
-        except httpx.HTTPStatusError as e:
-            error_detail = e.response.text if hasattr(e.response, "text") else str(e)
-            logger.error(
-                "[Hatchet] Modal mixdown HTTP error",
-                transcript_id=input.transcript_id,
-                status_code=e.response.status_code if hasattr(e, "response") else None,
-                error=error_detail,
-            )
-            raise RuntimeError(
-                f"Modal mixdown failed with HTTP {e.response.status_code}: {error_detail}"
-            )
-        except httpx.TimeoutException:
-            logger.error(
-                "[Hatchet] Modal mixdown timeout",
-                transcript_id=input.transcript_id,
-                timeout=settings.MIXDOWN_TIMEOUT,
-            )
-            raise RuntimeError(
-                f"Modal mixdown timeout after {settings.MIXDOWN_TIMEOUT}s"
-            )
-        except ValueError as e:
-            logger.error(
-                "[Hatchet] Modal mixdown validation error",
-                transcript_id=input.transcript_id,
-                error=str(e),
-            )
-            raise
-    else:
-        ctx.log("mixdown_tracks: using local backend")
-
-        # Existing local implementation
     output_path = tempfile.mktemp(suffix=".mp3")
     duration_ms_callback_capture_container = [0.0]
 
     async def capture_duration(d):
         duration_ms_callback_capture_container[0] = d
 
-        writer = AudioFileWriterProcessor(
-            path=output_path, on_duration=capture_duration
-        )
+    writer = AudioFileWriterProcessor(path=output_path, on_duration=capture_duration)
 
     await mixdown_tracks_pyav(
         valid_urls,
@@ -615,23 +530,18 @@ async def mixdown_tracks(input: PipelineInput, ctx: Context) -> MixdownResult:
         offsets_seconds=None,
         logger=logger,
         progress_callback=make_audio_progress_logger(ctx, TaskName.MIXDOWN_TRACKS),
-            expected_duration_sec=recording_duration
-            if recording_duration > 0
-            else None,
+        expected_duration_sec=recording_duration if recording_duration > 0 else None,
     )
     await writer.flush()
 
     file_size = Path(output_path).stat().st_size
+    storage_path = f"{input.transcript_id}/audio.mp3"
+
     with open(output_path, "rb") as mixed_file:
-            await storage.put_file(output_key, mixed_file)
+        await storage.put_file(storage_path, mixed_file)
 
     Path(output_path).unlink(missing_ok=True)
-        duration_ms = duration_ms_callback_capture_container[0]
-        tracks_mixed = len(valid_urls)
 
-        ctx.log(f"mixdown_tracks: local mixdown uploaded {file_size} bytes")
-
-    # Update DB (same for both backends)
     async with fresh_db_connection():
         from reflector.db.transcripts import transcripts_controller  # noqa: PLC0415
 
@@ -641,12 +551,12 @@ async def mixdown_tracks(input: PipelineInput, ctx: Context) -> MixdownResult:
                 transcript, {"audio_location": "storage"}
             )
 
-    ctx.log(f"mixdown_tracks complete: uploaded to {output_key}")
+    ctx.log(f"mixdown_tracks complete: uploaded {file_size} bytes to {storage_path}")
 
     return MixdownResult(
-        audio_key=output_key,
-        duration=duration_ms,
-        tracks_mixed=tracks_mixed,
+        audio_key=storage_path,
+        duration=duration_ms_callback_capture_container[0],
+        tracks_mixed=len(valid_urls),
     )
 
 

server/reflector/hatchet/workflows/topic_chunk_processing.py

@@ -7,11 +7,7 @@ Spawned dynamically by detect_topics via aio_run_many() for parallel processing.
 
 from datetime import timedelta
 
-from hatchet_sdk import (
-    ConcurrencyExpression,
-    ConcurrencyLimitStrategy,
-    Context,
-)
+from hatchet_sdk import ConcurrencyExpression, ConcurrencyLimitStrategy, Context
 from hatchet_sdk.rate_limit import RateLimit
 from pydantic import BaseModel
 
@@ -38,13 +34,11 @@ hatchet = HatchetClientManager.get_client()
 topic_chunk_workflow = hatchet.workflow(
     name="TopicChunkProcessing",
     input_validator=TopicChunkInput,
-    concurrency=[
-        ConcurrencyExpression(
+    concurrency=ConcurrencyExpression(
         expression="'global'",  # constant string = global limit across all runs
         max_runs=20,
         limit_strategy=ConcurrencyLimitStrategy.GROUP_ROUND_ROBIN,
-        )
-    ],
+    ),
 )
 
 

server/reflector/processors/audio_mixdown_modal.py

@@ -1,89 +0,0 @@
-"""
-Modal.com backend for audio mixdown.
-
-Uses Modal's CPU containers to offload audio mixing from Hatchet workers.
-Communicates via presigned S3 URLs for both input and output.
-"""
-
-import httpx
-from pydantic import BaseModel
-
-from reflector.settings import settings
-
-
-class MixdownResponse(BaseModel):
-    """Response from Modal mixdown endpoint."""
-
-    duration_ms: float
-    tracks_mixed: int
-    audio_uploaded: bool
-
-
-class AudioMixdownModalProcessor:
-    """Audio mixdown processor using Modal.com CPU backend.
-
-    Sends track URLs (presigned GET) and output URL (presigned PUT) to Modal.
-    Modal handles download, mixdown via PyAV, and upload.
-    """
-
-    def __init__(self, modal_api_key: str | None = None):
-        if not settings.MIXDOWN_URL:
-            raise ValueError("MIXDOWN_URL required to use AudioMixdownModalProcessor")
-
-        self.mixdown_url = settings.MIXDOWN_URL + "/v1"
-        self.timeout = settings.MIXDOWN_TIMEOUT
-        self.modal_api_key = modal_api_key or settings.MIXDOWN_MODAL_API_KEY
-
-        if not self.modal_api_key:
-            raise ValueError(
-                "MIXDOWN_MODAL_API_KEY required to use AudioMixdownModalProcessor"
-            )
-
-    async def mixdown(
-        self,
-        track_urls: list[str],
-        output_url: str,
-        target_sample_rate: int,
-        expected_duration_sec: float | None = None,
-    ) -> MixdownResponse:
-        """Mix multiple audio tracks via Modal backend.
-
-        Args:
-            track_urls: List of presigned GET URLs for audio tracks (non-empty)
-            output_url: Presigned PUT URL for output MP3
-            target_sample_rate: Sample rate for output (Hz, must be positive)
-            expected_duration_sec: Optional fallback duration if container metadata unavailable
-
-        Returns:
-            MixdownResponse with duration_ms, tracks_mixed, audio_uploaded
-
-        Raises:
-            ValueError: If track_urls is empty or target_sample_rate invalid
-            httpx.HTTPStatusError: On HTTP errors (404, 403, 500, etc.)
-            httpx.TimeoutException: On timeout
-        """
-        # Validate inputs
-        if not track_urls:
-            raise ValueError("track_urls cannot be empty")
-        if target_sample_rate <= 0:
-            raise ValueError(
-                f"target_sample_rate must be positive, got {target_sample_rate}"
-            )
-        if expected_duration_sec is not None and expected_duration_sec < 0:
-            raise ValueError(
-                f"expected_duration_sec cannot be negative, got {expected_duration_sec}"
-            )
-
-        async with httpx.AsyncClient(timeout=self.timeout) as client:
-            response = await client.post(
-                f"{self.mixdown_url}/audio/mixdown",
-                headers={"Authorization": f"Bearer {self.modal_api_key}"},
-                json={
-                    "track_urls": track_urls,
-                    "output_url": output_url,
-                    "target_sample_rate": target_sample_rate,
-                    "expected_duration_sec": expected_duration_sec,
-                },
-            )
-            response.raise_for_status()
-            return MixdownResponse(**response.json())

server/reflector/settings.py

@@ -98,17 +98,6 @@ class Settings(BaseSettings):
     # Diarization: local pyannote.audio
     DIARIZATION_PYANNOTE_AUTH_TOKEN: str | None = None
 
-    # Audio Mixdown
-    # backends:
-    #   - local: in-process PyAV mixdown (runs in same process as Hatchet worker)
-    #   - modal: HTTP API client to Modal.com CPU container
-    MIXDOWN_BACKEND: str = "local"
-    MIXDOWN_URL: str | None = None
-    MIXDOWN_TIMEOUT: int = 900  # 15 minutes
-
-    # Mixdown: modal backend
-    MIXDOWN_MODAL_API_KEY: str | None = None
-
     # Sentry
     SENTRY_DSN: str | None = None
 

server/runserver.sh

@@ -7,10 +7,8 @@ elif [ "${ENTRYPOINT}" = "worker" ]; then
     uv run celery -A reflector.worker.app worker --loglevel=info
 elif [ "${ENTRYPOINT}" = "beat" ]; then
     uv run celery -A reflector.worker.app beat --loglevel=info
-elif [ "${ENTRYPOINT}" = "hatchet-worker-cpu" ]; then
-    uv run python -m reflector.hatchet.run_workers_cpu
-elif [ "${ENTRYPOINT}" = "hatchet-worker-llm" ]; then
-    uv run python -m reflector.hatchet.run_workers_llm
+elif [ "${ENTRYPOINT}" = "hatchet-worker" ]; then
+    uv run python -m reflector.hatchet.run_workers
 else
     echo "Unknown command"
 fi

www/app/(app)/transcripts/[transcriptId]/_components/TopicList.tsx

@@ -1,12 +1,12 @@
 import React, { useState, useEffect } from "react";
 import ScrollToBottom from "../../scrollToBottom";
 import { Topic } from "../../webSocketTypes";
-import useParticipants from "../../useParticipants";
-import { Box, Flex, Text, Accordion } from "@chakra-ui/react";
-import { TopicItem } from "./TopicItem";
+import { Box, Flex, Text } from "@chakra-ui/react";
+import { formatTime } from "../../../../lib/time";
+import { getTopicColor } from "../../../../lib/topicColors";
 import { TranscriptStatus } from "../../../../lib/transcript";
-
 import { featureEnabled } from "../../../../lib/features";
+import { TOPICS_SCROLL_DIV_ID } from "./constants";
 
 type TopicListProps = {
   topics: Topic[];
@@ -18,6 +18,7 @@ type TopicListProps = {
   transcriptId: string;
   status: TranscriptStatus | null;
   currentTranscriptText: any;
+  onTopicClick?: (topicId: string) => void;
 };
 
 export function TopicList({
@@ -27,30 +28,13 @@ export function TopicList({
   transcriptId,
   status,
   currentTranscriptText,
+  onTopicClick,
 }: TopicListProps) {
   const [activeTopic, setActiveTopic] = useActiveTopic;
+  const [hoveredTopicId, setHoveredTopicId] = useState<string | null>(null);
   const [autoscrollEnabled, setAutoscrollEnabled] = useState<boolean>(true);
-  const participants = useParticipants(transcriptId);
 
-  const scrollToTopic = () => {
-    const topicDiv = document.getElementById(`topic-${activeTopic?.id}`);
-
-    setTimeout(() => {
-      topicDiv?.scrollIntoView({
-        behavior: "smooth",
-        block: "start",
-        inline: "nearest",
-      });
-    }, 200);
-  };
-
-  useEffect(() => {
-    if (activeTopic && autoscroll) scrollToTopic();
-  }, [activeTopic, autoscroll]);
-
-  // scroll top is not rounded, heights are, so exact match won't work.
-  // https://developer.mozilla.org/en-US/docs/Web/API/Element/scrollHeight#determine_if_an_element_has_been_totally_scrolled
-  const toggleScroll = (element) => {
+  const toggleScroll = (element: HTMLElement) => {
     const bottom =
       Math.abs(
         element.scrollHeight - element.clientHeight - element.scrollTop,
@@ -61,14 +45,19 @@ export function TopicList({
       setAutoscrollEnabled(true);
     }
   };
-  const handleScroll = (e) => {
-    toggleScroll(e.target);
+
+  const handleScroll = (e: React.UIEvent<HTMLDivElement>) => {
+    toggleScroll(e.target as HTMLElement);
+  };
+
+  const scrollToBottom = () => {
+    const topicsDiv = document.getElementById(TOPICS_SCROLL_DIV_ID);
+    if (topicsDiv) topicsDiv.scrollTop = topicsDiv.scrollHeight;
   };
 
   useEffect(() => {
     if (autoscroll) {
-      const topicsDiv = document.getElementById("scroll-div");
-
+      const topicsDiv = document.getElementById(TOPICS_SCROLL_DIV_ID);
       topicsDiv && toggleScroll(topicsDiv);
     }
   }, [activeTopic, autoscroll]);
@@ -77,37 +66,41 @@ export function TopicList({
     if (autoscroll && autoscrollEnabled) scrollToBottom();
   }, [topics.length, currentTranscriptText]);
 
-  const scrollToBottom = () => {
-    const topicsDiv = document.getElementById("scroll-div");
-
-    if (topicsDiv) topicsDiv.scrollTop = topicsDiv.scrollHeight;
-  };
-
-  const getSpeakerName = (speakerNumber: number) => {
-    if (!participants.response) return;
-    return (
-      participants.response.find(
-        (participant) => participant.speaker == speakerNumber,
-      )?.name || `Speaker ${speakerNumber}`
-    );
-  };
-
-  const requireLogin = featureEnabled("requireLogin");
-
   useEffect(() => {
     if (autoscroll) {
       setActiveTopic(topics[topics.length - 1]);
     }
   }, [topics, autoscroll]);
 
+  const handleTopicClick = (topic: Topic) => {
+    setActiveTopic(topic);
+    if (onTopicClick) {
+      onTopicClick(topic.id);
+    }
+  };
+
+  const handleTopicMouseEnter = (topic: Topic) => {
+    setHoveredTopicId(topic.id);
+    // If already active, toggle off when mousing over
+    if (activeTopic?.id === topic.id) {
+      setActiveTopic(null);
+    } else {
+      setActiveTopic(topic);
+    }
+  };
+
+  const handleTopicMouseLeave = () => {
+    setHoveredTopicId(null);
+  };
+
+  const requireLogin = featureEnabled("requireLogin");
+
   return (
     <Flex
-      position={"relative"}
-      w={"100%"}
-      h={"95%"}
-      flexDirection={"column"}
-      justify={"center"}
-      align={"center"}
+      position="relative"
+      w="full"
+      h="200px"
+      flexDirection="column"
       flexShrink={0}
     >
       {autoscroll && (
@@ -118,45 +111,71 @@ export function TopicList({
       )}
 
       <Box
-        id="scroll-div"
-        overflowY={"auto"}
-        h={"100%"}
+        id={TOPICS_SCROLL_DIV_ID}
+        overflowY="auto"
+        h="full"
         onScroll={handleScroll}
         width="full"
       >
         {topics.length > 0 && (
-          <Accordion.Root
-            multiple={false}
-            collapsible={true}
-            value={activeTopic ? [activeTopic.id] : []}
-            onValueChange={(details) => {
-              const selectedTopicId = details.value[0];
-              const selectedTopic = selectedTopicId
-                ? topics.find((t) => t.id === selectedTopicId)
-                : null;
-              setActiveTopic(selectedTopic || null);
-            }}
-          >
-            {topics.map((topic) => (
-              <TopicItem
+          <Flex direction="column" gap={1} p={2}>
+            {topics.map((topic, index) => {
+              const color = getTopicColor(index);
+              const isActive = activeTopic?.id === topic.id;
+              const isHovered = hoveredTopicId === topic.id;
+
+              return (
+                <Flex
                   key={topic.id}
-                topic={topic}
-                isActive={activeTopic?.id === topic.id}
-                getSpeakerName={getSpeakerName}
+                  id={`topic-${topic.id}`}
+                  gap={2}
+                  align="center"
+                  py={1}
+                  px={2}
+                  cursor="pointer"
+                  bg={isActive || isHovered ? "gray.100" : "transparent"}
+                  _hover={{ bg: "gray.50" }}
+                  onClick={() => handleTopicClick(topic)}
+                  onMouseEnter={() => handleTopicMouseEnter(topic)}
+                  onMouseLeave={handleTopicMouseLeave}
+                >
+                  {/* Color indicator */}
+                  <Box
+                    w="12px"
+                    h="12px"
+                    borderRadius="full"
+                    bg={color}
+                    flexShrink={0}
                   />
-            ))}
-          </Accordion.Root>
+
+                  {/* Topic title */}
+                  <Text
+                    flex={1}
+                    fontSize="sm"
+                    fontWeight={isActive ? "semibold" : "normal"}
+                  >
+                    {topic.title}
+                  </Text>
+
+                  {/* Timestamp */}
+                  <Text as="span" color="gray.500" fontSize="xs" flexShrink={0}>
+                    {formatTime(topic.timestamp)}
+                  </Text>
+                </Flex>
+              );
+            })}
+          </Flex>
         )}
 
         {status == "recording" && (
-          <Box textAlign={"center"}>
+          <Box textAlign="center">
             <Text>{currentTranscriptText}</Text>
           </Box>
         )}
         {(status == "recording" || status == "idle") &&
           currentTranscriptText.length == 0 &&
           topics.length == 0 && (
-            <Box textAlign={"center"} color="gray">
+            <Box textAlign="center" color="gray">
               <Text>
                 Full discussion transcript will appear here after you start
                 recording.
@@ -167,7 +186,7 @@ export function TopicList({
             </Box>
           )}
         {status == "processing" && (
-          <Box textAlign={"center"} color="gray">
+          <Box textAlign="center" color="gray">
             <Text>We are processing the recording, please wait.</Text>
             {!requireLogin && (
               <span>
@@ -177,12 +196,12 @@ export function TopicList({
           </Box>
         )}
         {status == "ended" && topics.length == 0 && (
-          <Box textAlign={"center"} color="gray">
+          <Box textAlign="center" color="gray">
             <Text>Recording has ended without topics being found.</Text>
           </Box>
         )}
         {status == "error" && (
-          <Box textAlign={"center"} color="gray">
+          <Box textAlign="center" color="gray">
             <Text>There was an error processing your recording</Text>
           </Box>
         )}

www/app/(app)/transcripts/[transcriptId]/_components/TranscriptWithGutter.tsx

@@ -0,0 +1,106 @@
+import { Box, Text, IconButton } from "@chakra-ui/react";
+import { ChevronUp } from "lucide-react";
+import { Topic } from "../../webSocketTypes";
+import { getTopicColor } from "../../../../lib/topicColors";
+import { TOPICS_SCROLL_DIV_ID } from "./constants";
+
+interface TranscriptWithGutterProps {
+  topics: Topic[];
+  getSpeakerName: (speakerNumber: number) => string | undefined;
+  onGutterClick: (topicId: string) => void;
+}
+
+export function TranscriptWithGutter({
+  topics,
+  getSpeakerName,
+  onGutterClick,
+}: TranscriptWithGutterProps) {
+  const scrollToTopics = () => {
+    // Scroll to the topic list at the top
+    const topicList = document.getElementById(TOPICS_SCROLL_DIV_ID);
+    if (topicList) {
+      topicList.scrollIntoView({
+        behavior: "smooth",
+        block: "start",
+      });
+    }
+  };
+
+  return (
+    <Box>
+      {topics.map((topic, topicIndex) => {
+        const color = getTopicColor(topicIndex);
+
+        return (
+          <Box key={topic.id} position="relative">
+            {/* Topic Header with Up Button */}
+            <Box
+              py={3}
+              px={4}
+              fontWeight="semibold"
+              fontSize="lg"
+              display="flex"
+              alignItems="center"
+              justifyContent="space-between"
+            >
+              <Text>{topic.title}</Text>
+              <IconButton
+                aria-label="Scroll to topics"
+                size="sm"
+                variant="ghost"
+                onClick={scrollToTopics}
+              >
+                <ChevronUp size={16} />
+              </IconButton>
+            </Box>
+
+            {/* Segments container with single gutter */}
+            <Box position="relative">
+              {/* Single continuous gutter for entire topic */}
+              <Box
+                className="topic-gutter"
+                position="absolute"
+                left={0}
+                top={0}
+                bottom={0}
+                width="4px"
+                bg={color}
+                cursor="pointer"
+                transition="all 0.2s"
+                _hover={{
+                  filter: "brightness(1.2)",
+                  width: "6px",
+                }}
+                onClick={() => onGutterClick(topic.id)}
+              />
+
+              {/* Segments */}
+              {topic.segments?.map((segment, segmentIndex) => (
+                <Box
+                  key={segmentIndex}
+                  id={`segment-${topic.id}-${segmentIndex}`}
+                  py={2}
+                  px={4}
+                  pl={12}
+                  _hover={{
+                    bg: "gray.50",
+                  }}
+                >
+                  {/* Segment Content */}
+                  <Text fontSize="sm">
+                    <Text as="span" fontWeight="semibold" color="gray.700">
+                      {getSpeakerName(segment.speaker) ||
+                        `Speaker ${segment.speaker}`}
+                      :
+                    </Text>{" "}
+                    {segment.text}
+                  </Text>
+                </Box>
+              ))}
+            </Box>
+          </Box>
+        );
+      })}
+    </Box>
+  );
+}

www/app/(app)/transcripts/[transcriptId]/_components/constants.ts

@@ -0,0 +1 @@
+export const TOPICS_SCROLL_DIV_ID = "topics-scroll-div";

www/app/(app)/transcripts/[transcriptId]/page.tsx

@@ -3,7 +3,9 @@ import Modal from "../modal";
 import useTopics from "../useTopics";
 import useWaveform from "../useWaveform";
 import useMp3 from "../useMp3";
+import useParticipants from "../useParticipants";
 import { TopicList } from "./_components/TopicList";
+import { TranscriptWithGutter } from "./_components/TranscriptWithGutter";
 import { Topic } from "../webSocketTypes";
 import React, { useEffect, useState, use } from "react";
 import FinalSummary from "./finalSummary";
@@ -45,14 +47,91 @@ export default function TranscriptDetails(details: TranscriptDetails) {
 
   const mp3 = useMp3(transcriptId, waiting);
   const topics = useTopics(transcriptId);
+  const participants = useParticipants(transcriptId);
   const waveform = useWaveform(
     transcriptId,
     waiting || mp3.audioDeleted === true,
   );
   const useActiveTopic = useState<Topic | null>(null);
+  const [activeTopic, setActiveTopic] = useActiveTopic;
   const [finalSummaryElement, setFinalSummaryElement] =
     useState<HTMLDivElement | null>(null);
 
+  // IntersectionObserver for active topic detection based on scroll position
+  useEffect(() => {
+    if (!topics.topics || topics.topics.length === 0) return;
+
+    const observer = new IntersectionObserver(
+      (entries) => {
+        // Find the most visible segment
+        let mostVisibleEntry: IntersectionObserverEntry | null = null;
+        let maxRatio = 0;
+
+        entries.forEach((entry) => {
+          if (entry.isIntersecting && entry.intersectionRatio > maxRatio) {
+            maxRatio = entry.intersectionRatio;
+            mostVisibleEntry = entry;
+          }
+        });
+
+        if (mostVisibleEntry) {
+          // Extract topicId from segment id (format: "segment-{topicId}-{idx}")
+          const segmentId = mostVisibleEntry.target.id;
+          const match = segmentId.match(/^segment-([^-]+)-/);
+          if (match) {
+            const topicId = match[1];
+            const topic = topics.topics?.find((t) => t.id === topicId);
+            if (topic && activeTopic?.id !== topic.id) {
+              setActiveTopic(topic);
+            }
+          }
+        }
+      },
+      {
+        threshold: [0, 0.25, 0.5, 0.75, 1],
+        rootMargin: "-20% 0px -20% 0px",
+      },
+    );
+
+    // Observe all segment elements
+    const segments = document.querySelectorAll('[id^="segment-"]');
+    segments.forEach((segment) => observer.observe(segment));
+
+    return () => observer.disconnect();
+  }, [topics.topics, activeTopic?.id, setActiveTopic]);
+
+  // Scroll handlers for bidirectional navigation
+  const handleTopicClick = (topicId: string) => {
+    // Scroll to first segment of this topic in transcript
+    const firstSegment = document.querySelector(`[id^="segment-${topicId}-"]`);
+    if (firstSegment) {
+      firstSegment.scrollIntoView({
+        behavior: "smooth",
+        block: "center",
+      });
+    }
+  };
+
+  const handleGutterClick = (topicId: string) => {
+    // Scroll to topic in list
+    const topicChip = document.getElementById(`topic-${topicId}`);
+    if (topicChip) {
+      topicChip.scrollIntoView({
+        behavior: "smooth",
+        block: "center",
+      });
+    }
+  };
+
+  const getSpeakerName = (speakerNumber: number) => {
+    if (!participants.response) return `Speaker ${speakerNumber}`;
+    return (
+      participants.response.find(
+        (participant) => participant.speaker == speakerNumber,
+      )?.name || `Speaker ${speakerNumber}`
+    );
+  };
+
   useEffect(() => {
     if (!waiting || !transcript.data) return;
 
@@ -121,7 +200,7 @@ export default function TranscriptDetails(details: TranscriptDetails) {
     <>
       <Grid
         templateColumns="1fr"
-        templateRows="auto minmax(0, 1fr)"
+        templateRows="auto auto"
         gap={4}
         mt={4}
         mb={4}
@@ -153,18 +232,18 @@ export default function TranscriptDetails(details: TranscriptDetails) {
         <Grid
           templateColumns={{ base: "minmax(0, 1fr)", md: "repeat(2, 1fr)" }}
           templateRows={{
-            base: "auto minmax(0, 1fr) minmax(0, 1fr)",
-            md: "auto minmax(0, 1fr)",
+            base: "auto auto auto",
+            md: "auto auto",
           }}
           gap={4}
           gridRowGap={2}
           padding={4}
-          paddingBottom={0}
           background="gray.bg"
           border={"2px solid"}
           borderColor={"gray.bg"}
           borderRadius={8}
         >
+          {/* Title */}
           <GridItem colSpan={{ base: 1, md: 2 }}>
             <Flex direction="column" gap={0}>
               <Flex alignItems="center" gap={2}>
@@ -187,6 +266,9 @@ export default function TranscriptDetails(details: TranscriptDetails) {
               )}
             </Flex>
           </GridItem>
+
+          {/* Left column: Topics List */}
+          <GridItem display="flex" flexDirection="column" gap={4} h="100%">
             <TopicList
               topics={topics.topics || []}
               useActiveTopic={useActiveTopic}
@@ -194,9 +276,43 @@ export default function TranscriptDetails(details: TranscriptDetails) {
               transcriptId={transcriptId}
               status={transcript.data?.status || null}
               currentTranscriptText=""
+              onTopicClick={handleTopicClick}
             />
+
+            {/* Transcript with colored gutter (scrollable) */}
+            {topics.topics && topics.topics.length > 0 && (
+              <Box
+                overflowY="auto"
+                flex={1}
+                minH="0"
+                pr={2}
+                css={{
+                  "&::-webkit-scrollbar": {
+                    width: "8px",
+                  },
+                  "&::-webkit-scrollbar-track": {
+                    background: "transparent",
+                  },
+                  "&::-webkit-scrollbar-thumb": {
+                    background: "#CBD5E0",
+                    borderRadius: "4px",
+                  },
+                  "&::-webkit-scrollbar-thumb:hover": {
+                    background: "#A0AEC0",
+                  },
+                }}
+              >
+                <TranscriptWithGutter
+                  topics={topics.topics}
+                  getSpeakerName={getSpeakerName}
+                  onGutterClick={handleGutterClick}
+                />
+              </Box>
+            )}
+          </GridItem>
+
+          {/* Right column: Final Summary */}
           {transcript.data && topics.topics ? (
-            <>
             <FinalSummary
               transcript={transcript.data}
               topics={topics.topics}
@@ -205,10 +321,9 @@ export default function TranscriptDetails(details: TranscriptDetails) {
               }}
               finalSummaryRef={setFinalSummaryElement}
             />
-            </>
           ) : (
-            <Flex justify={"center"} alignItems={"center"} h={"100%"}>
-              <div className="flex flex-col h-full justify-center content-center">
+            <Flex justify="center" alignItems="center" h="100%">
+              <Flex direction="column" h="full" justify="center" align="center">
                 {transcript?.data?.status == "processing" ? (
                   <Text>Loading Transcript</Text>
                 ) : (
@@ -217,7 +332,7 @@ export default function TranscriptDetails(details: TranscriptDetails) {
                     back later
                   </Text>
                 )}
-              </div>
+              </Flex>
             </Flex>
           )}
         </Grid>

www/app/lib/topicColors.ts

@@ -0,0 +1,18 @@
+// Predefined color palette for topics
+// Colors chosen for good contrast and visual distinction
+export const TOPIC_COLORS = [
+  "#3B82F6", // blue
+  "#10B981", // green
+  "#F59E0B", // amber
+  "#EF4444", // red
+  "#8B5CF6", // violet
+  "#EC4899", // pink
+  "#14B8A6", // teal
+  "#F97316", // orange
+  "#6366F1", // indigo
+  "#84CC16", // lime
+] as const;
+
+export function getTopicColor(topicIndex: number): string {
+  return TOPIC_COLORS[topicIndex % TOPIC_COLORS.length];
+}