diff --git a/.dockerignore b/.dockerignore
index 9e5635b..f446d9e 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -13,4 +13,3 @@ tests
 .ruff_cache
 .idea
 .vscode
-README.md
diff --git a/.gitignore b/.gitignore
index cb79ced..7a836be 100644
--- a/.gitignore
+++ b/.gitignore
@@ -19,3 +19,7 @@ data/work/*
 !data/work/.gitkeep
 *.log
 .DS_Store
+
+# local preview launch config
+frontend/.claude/
+.claude/launch.json
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 59b5b1e..bd0883a 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -6,8 +6,19 @@ ENV PYTHONUNBUFFERED=1 \
     PIP_DISABLE_PIP_VERSION_CHECK=1 \
     DEBIAN_FRONTEND=noninteractive
 
+# Switch apt to a faster mirror (Yandex) before installing. The default
+# deb.debian.org Cloudflare CDN throttles to ~150 kB/s from some networks,
+# stalling the build on gcc-12/cpp-12; Yandex serves consistently faster.
+RUN sed -i 's|deb.debian.org|mirror.yandex.ru|g' /etc/apt/sources.list.d/debian.sources 2>/dev/null \
+ || sed -i 's|deb.debian.org|mirror.yandex.ru|g' /etc/apt/sources.list 2>/dev/null \
+ || true
+
 # System deps for OCRmyPDF + Tesseract (rus+eng) + Ghostscript + qpdf + image libs
-RUN apt-get update && apt-get install -y --no-install-recommends \
+RUN apt-get update \
+ && apt-get install -y --no-install-recommends \
+        --fix-missing -o Acquire::Retries=10 \
+        -o Acquire::http::Timeout=180 \
+        -o Acquire::https::Timeout=180 \
         build-essential \
         curl \
         ca-certificates \
@@ -33,14 +44,15 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 
 WORKDIR /app
 
-COPY pyproject.toml /app/pyproject.toml
-
-RUN pip install --upgrade pip wheel setuptools && \
-    pip install -e .
-
+# Copy the metadata + package payload BEFORE pip install. hatchling validates
+# README.md and the [packages] entries (app, scripts) at editable-install time;
+# missing files cause `Readme file does not exist` even with `pip install -e .`.
+COPY pyproject.toml README.md alembic.ini /app/
 COPY app /app/app
 COPY scripts /app/scripts
-COPY alembic.ini /app/alembic.ini
+
+RUN pip install --upgrade pip wheel setuptools \
+ && pip install -e .
 
 RUN mkdir -p /data/input /data/work