vanilla: build pinned V 0.5.1 from source (pinned vc bootstrap)

Build V from source at the 0.5.1 tag instead of the prebuilt release zip.
Plain `make` can't build an old tag: its latest_vc step `git pull`s the
newest vlang/vc bootstrap, which no longer matches 0.5.1's vlib (fails with
`unknown ident \`native\``). So pin vc to the commit cut for 0.5.1
(vlang/vc f461dfeb = "[v:master] 0c3183c - V 0.5.1") and run make's own
bootstrap recipe (cc -> v1 -> v2 -> v). Drop curl/unzip from the build deps.

Pinned by tag, not a master commit, because post-0.5.1 master carries a
codegen regression (single-element array push 4-7x slower, vlang/v#27468).
Both backends; verified the source-built compiler serves /json and /pipeline
correctly.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: enghitalo

frameworks/vanilla-epoll/Dockerfile

@@ -2,13 +2,26 @@ FROM debian:stable-slim AS build
 
 RUN apt-get -qq update && \
     apt-get -qy install --no-install-recommends \
-        ca-certificates curl unzip build-essential git libpq-dev liburing-dev && \
+        ca-certificates build-essential git libpq-dev liburing-dev && \
     rm -rf /var/lib/apt/lists/*
 
-# Pinned, reproducible V 0.5.1 (prebuilt release binary — no source build, and it
-# avoids the `git checkout <tag> && make` vc-mismatch problem).
-RUN curl -fsSL https://github.com/vlang/v/releases/download/0.5.1/v_linux.zip -o /tmp/v.zip && \
-    unzip -q /tmp/v.zip -d /opt && rm /tmp/v.zip && \
+# Pinned, reproducible V 0.5.1, built from source. Plain `make` can't build an old
+# tag — its `latest_vc` step `git pull`s the newest vlang/vc bootstrap, which no
+# longer matches 0.5.1's vlib ("unknown ident `native`"). So pin the vc bootstrap
+# to the commit cut for 0.5.1 (vlang/vc f461dfeb = "[v:master] 0c3183c - V 0.5.1")
+# and run make's own bootstrap recipe (cc -> v1 -> v2 -> v). Pinned by tag, not a
+# master commit, because post-0.5.1 master has a codegen regression (single-element
+# array push 4-7x slower, vlang/v#27468).
+RUN git clone --branch 0.5.1 --depth 1 https://github.com/vlang/v /opt/v && \
+    git clone --filter=blob:none --quiet https://github.com/vlang/vc /opt/v/vc && \
+    git -C /opt/v/vc checkout -q f461dfebcdfa && \
+    git clone --filter=blob:none --quiet --branch thirdparty-linux-amd64 \
+        https://github.com/vlang/tccbin /opt/v/thirdparty/tcc && \
+    cd /opt/v && \
+    cc -std=c99 -w -o v1 vc/v.c -lm -lpthread && \
+    ./v1 -no-parallel -o v2 cmd/v && \
+    ./v2 -nocache -o v cmd/v && \
+    rm -f v1 v2 && \
     ln -s /opt/v/v /usr/local/bin/v
 
 # Install the vanilla HTTP server as the `vanilla` module (import vanilla.http_server).

frameworks/vanilla-io_uring/Dockerfile

@@ -2,13 +2,26 @@ FROM debian:stable-slim AS build
 
 RUN apt-get -qq update && \
     apt-get -qy install --no-install-recommends \
-        ca-certificates curl unzip build-essential git libpq-dev liburing-dev && \
+        ca-certificates build-essential git libpq-dev liburing-dev && \
     rm -rf /var/lib/apt/lists/*
 
-# Pinned, reproducible V 0.5.1 (prebuilt release binary — no source build, and it
-# avoids the `git checkout <tag> && make` vc-mismatch problem).
-RUN curl -fsSL https://github.com/vlang/v/releases/download/0.5.1/v_linux.zip -o /tmp/v.zip && \
-    unzip -q /tmp/v.zip -d /opt && rm /tmp/v.zip && \
+# Pinned, reproducible V 0.5.1, built from source. Plain `make` can't build an old
+# tag — its `latest_vc` step `git pull`s the newest vlang/vc bootstrap, which no
+# longer matches 0.5.1's vlib ("unknown ident `native`"). So pin the vc bootstrap
+# to the commit cut for 0.5.1 (vlang/vc f461dfeb = "[v:master] 0c3183c - V 0.5.1")
+# and run make's own bootstrap recipe (cc -> v1 -> v2 -> v). Pinned by tag, not a
+# master commit, because post-0.5.1 master has a codegen regression (single-element
+# array push 4-7x slower, vlang/v#27468).
+RUN git clone --branch 0.5.1 --depth 1 https://github.com/vlang/v /opt/v && \
+    git clone --filter=blob:none --quiet https://github.com/vlang/vc /opt/v/vc && \
+    git -C /opt/v/vc checkout -q f461dfebcdfa && \
+    git clone --filter=blob:none --quiet --branch thirdparty-linux-amd64 \
+        https://github.com/vlang/tccbin /opt/v/thirdparty/tcc && \
+    cd /opt/v && \
+    cc -std=c99 -w -o v1 vc/v.c -lm -lpthread && \
+    ./v1 -no-parallel -o v2 cmd/v && \
+    ./v2 -nocache -o v cmd/v && \
+    rm -f v1 v2 && \
     ln -s /opt/v/v /usr/local/bin/v
 
 # Install the vanilla HTTP server as the `vanilla` module (import vanilla.http_server).