v0.7.8 - Fully static builds implemented with musl-gcc

Dockerfile.alpine-musl

@@ -28,7 +28,7 @@ RUN apk add --no-cache \
 # Set working directory
 WORKDIR /build
 
-# Build libsecp256k1 static
+# Build libsecp256k1 static (cached layer - only rebuilds if Alpine version changes)
 RUN cd /tmp && \
     git clone https://github.com/bitcoin-core/secp256k1.git && \
     cd secp256k1 && \
@@ -39,7 +39,7 @@ RUN cd /tmp && \
     make install && \
     rm -rf /tmp/secp256k1
 
-# Build libwebsockets static with minimal features
+# Build libwebsockets static with minimal features (cached layer)
 RUN cd /tmp && \
     git clone --depth 1 --branch v4.3.3 https://github.com/warmcat/libwebsockets.git && \
     cd libwebsockets && \
@@ -63,23 +63,33 @@ RUN cd /tmp && \
     make install && \
     rm -rf /tmp/libwebsockets
 
-# Copy c-relay source
-COPY . /build/
+# Copy only submodule configuration and git directory
+COPY .gitmodules /build/.gitmodules
+COPY .git /build/.git
 
 # Clean up any stale submodule references (nips directory is not a submodule)
 RUN git rm --cached nips 2>/dev/null || true
 
-# Initialize submodules and build nostr_core_lib with required NIPs
+# Initialize submodules (cached unless .gitmodules changes)
+RUN git submodule update --init --recursive
+
+# Copy nostr_core_lib source files (cached unless nostr_core_lib changes)
+COPY nostr_core_lib /build/nostr_core_lib/
+
+# Build nostr_core_lib with required NIPs (cached unless nostr_core_lib changes)
 # Disable fortification in build.sh to prevent __*_chk symbol issues
 # NIPs: 001(Basic), 006(Keys), 013(PoW), 017(DMs), 019(Bech32), 044(Encryption), 059(Gift Wrap - required by NIP-17)
-RUN git submodule update --init --recursive && \
-    cd nostr_core_lib && \
+RUN cd nostr_core_lib && \
     chmod +x build.sh && \
     sed -i 's/CFLAGS="-Wall -Wextra -std=c99 -fPIC -O2"/CFLAGS="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=0 -Wall -Wextra -std=c99 -fPIC -O2"/' build.sh && \
     rm -f *.o *.a 2>/dev/null || true && \
     ./build.sh --nips=1,6,13,17,19,44,59
 
-# Build c-relay with full static linking
+# Copy c-relay source files LAST (only this layer rebuilds on source changes)
+COPY src/ /build/src/
+COPY Makefile /build/Makefile
+
+# Build c-relay with full static linking (only rebuilds when src/ changes)
 # Disable fortification to avoid __*_chk symbols that don't exist in MUSL
 RUN gcc -static -O2 -Wall -Wextra -std=c99 \
     -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=0 \