diff --git a/Dockerfile b/Dockerfile
index 095d567..19c16fa 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -4,6 +4,7 @@
 ARG PG_VERSION=17
 ARG PGVECTOR_VERSION=0.8.0
 ARG POSTGIS_VERSION=3.5.1
+ARG PG_TEXTSEARCH_VERSION=0.2.0
 ARG PGSODIUM_VERSION=3.1.9
 
 #############################################
@@ -13,6 +14,7 @@ FROM postgres:${PG_VERSION}-alpine AS builder
 
 ARG PGVECTOR_VERSION
 ARG POSTGIS_VERSION
+ARG PG_TEXTSEARCH_VERSION
 ARG PGSODIUM_VERSION
 
 RUN apk add --no-cache \
@@ -30,7 +32,11 @@ RUN apk add --no-cache \
     protobuf-c-dev \
     libxml2-dev \
     pcre2-dev \
-    libsodium-dev
+    libsodium-dev \
+    # PostGIS build tools
+    perl \
+    flex \
+    bison
 
 WORKDIR /build
 
@@ -51,8 +57,10 @@ RUN curl -L https://download.osgeo.org/postgis/source/postgis-${POSTGIS_VERSION}
     make install
 
 # pg_textsearch (BM25)
-RUN git clone --depth 1 https://github.com/timescale/pg_textsearch.git && \
+RUN git clone --branch v${PG_TEXTSEARCH_VERSION} --depth 1 https://github.com/timescale/pg_textsearch.git && \
     cd pg_textsearch && \
+    # Fix missing math.h include (upstream bug)
+    sed -i '1i #include <math.h>' src/am/build.c && \
     make -j$(nproc) && \
     make install