Tidy

build-base/Dockerfile.dropshell-build-base

@@ -228,3 +228,19 @@ RUN git clone --recurse-submodules https://github.com/drogonframework/drogon.git
     make -j$(nproc) && \
     make install && \
     cd / && rm -rf /tmp/drogon
+
+# Build nlohmann/json library (header-only, but we'll install it properly)
+ARG NLOHMANN_JSON_VERSION=3.11.3
+WORKDIR /tmp
+RUN curl -LO https://github.com/nlohmann/json/archive/refs/tags/v${NLOHMANN_JSON_VERSION}.tar.gz && \
+    tar xzf v${NLOHMANN_JSON_VERSION}.tar.gz && \
+    cd json-${NLOHMANN_JSON_VERSION} && \
+    mkdir build && cd build && \
+    cmake .. \
+      -DCMAKE_BUILD_TYPE=Release \
+      -DCMAKE_INSTALL_PREFIX=/usr/local \
+      -DJSON_BuildTests=OFF \
+      -DJSON_Install=ON && \
+    make -j$(nproc) && \
+    make install && \
+    cd / && rm -rf /tmp/json-${NLOHMANN_JSON_VERSION} /tmp/v${NLOHMANN_JSON_VERSION}.tar.gz