diff --git a/Dockerfile.full b/Dockerfile.full
index 4539799..a972daf 100755
--- a/Dockerfile.full
+++ b/Dockerfile.full
@@ -4,7 +4,7 @@ ENV DEBIAN_FRONTEND=noninteractive PYTHONUNBUFFERED=1 LC_ALL=C.UTF-8 LANG=C.UTF-
 RUN apt-get update && apt-get install -y --no-install-recommends \
     ca-certificates curl git make emacs-nox python3 python3-pip python3-matplotlib \
     latexmk biber texlive-full && rm -rf /var/lib/apt/lists/*
-RUN useradd -m -u 1000 builder
+RUN useradd -m -s /bin/bash builder || true
 WORKDIR /work
 USER builder
 CMD ["bash", "-lc", "make VENUE=arxiv"]
diff --git a/Dockerfile.tinytex b/Dockerfile.tinytex
index 566f4c2..c768658 100755
--- a/Dockerfile.tinytex
+++ b/Dockerfile.tinytex
@@ -1,14 +1,38 @@
 # syntax=docker/dockerfile:1
 FROM ubuntu:24.04
-ENV DEBIAN_FRONTEND=noninteractive PYTHONUNBUFFERED=1 LC_ALL=C.UTF-8 LANG=C.UTF-8 PATH=/opt/TinyTeX/bin/x86_64-linux:$PATH
+
+ENV DEBIAN_FRONTEND=noninteractive \
+    PYTHONUNBUFFERED=1 \
+    LC_ALL=C.UTF-8 \
+    LANG=C.UTF-8 \
+    TINYTEX_DIR=/opt/TinyTeX \
+    PATH=/opt/TinyTeX/bin/x86_64-linux:$PATH
+
+# Tools that the TinyTeX installer uses (wget, tar, xz) + our stack
 RUN apt-get update && apt-get install -y --no-install-recommends \
-    ca-certificates curl git make emacs-nox python3 python3-pip python3-matplotlib perl && \
-    rm -rf /var/lib/apt/lists/*
-RUN curl -sL https://yihui.org/tinytex/install-unx.sh | sh -s - --admin --no-path && \
-    /opt/TinyTeX/bin/*/tlmgr path add && \
-    tlmgr install latexmk biber latex-bin biblatex hyperref geometry microtype etoolbox enumitem xcolor listings IEEEtran acmart elsarticle && \
-    tlmgr path add
-RUN useradd -m -u 1000 builder
+      ca-certificates \
+      curl wget tar xz-utils \
+      git make \
+      emacs-nox \
+      python3 python3-pip python3-matplotlib \
+      perl \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install TinyTeX *into /opt/TinyTeX* and set up tlmgr on PATH
+# (we call tlmgr via its absolute path once, then rely on the symlinks it creates)
+RUN curl -fsSL https://yihui.org/tinytex/install-unx.sh \
+      | TINYTEX_DIR="$TINYTEX_DIR" sh -s - --admin --no-path \
+ && "$TINYTEX_DIR"/bin/*/tlmgr path add \
+ && "$TINYTEX_DIR"/bin/*/tlmgr option repository http://mirror.ctan.org/systems/texlive/tlnet \
+ && "$TINYTEX_DIR"/bin/*/tlmgr update --self \
+ && "$TINYTEX_DIR"/bin/*/tlmgr install \
+      latexmk biber latex-bin biblatex hyperref geometry microtype etoolbox enumitem \
+      xcolor listings ieeetran acmart elsarticle \
+ && fmtutil-sys --all
+
+# Non-root user (maps nicer to host file perms)
+RUN useradd -m -s /bin/bash builder || true
 WORKDIR /work
 USER builder
+
 CMD ["bash", "-lc", "make VENUE=arxiv"]