diff --git a/.github/workflows/update_backend_version.py b/.github/workflows/update_backend_version.py
index 5a000201..696da9f5 100644
--- a/.github/workflows/update_backend_version.py
+++ b/.github/workflows/update_backend_version.py
@@ -20,7 +20,7 @@
 major, minor, patch, *dev = pyproject_data["project"]["version"].split(".")
 pyproject_data["project"]["version"] = f"{major}.{minor}.{int(patch)+1}"
 
-juliapkg_data["packages"]["SymbolicRegression"]["rev"] = f"v{new_backend_version}"
+juliapkg_data["packages"]["SymbolicRegression"]["version"] = f"={new_backend_version}"
 
 with open(pyproject_toml, "w") as toml_file:
     toml_file.write(tomlkit.dumps(pyproject_data))
diff --git a/pyproject.toml b/pyproject.toml
index 9577862a..1ba9d492 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "pysr"
-version = "0.18.0"
+version = "0.18.1"
 authors = [
     {name = "Miles Cranmer", email = "miles.cranmer@gmail.com"},
 ]
diff --git a/pysr/juliapkg.json b/pysr/juliapkg.json
index 60ded254..ee8d2c02 100644
--- a/pysr/juliapkg.json
+++ b/pysr/juliapkg.json
@@ -3,8 +3,7 @@
     "packages": {
         "SymbolicRegression": {
             "uuid": "8254be44-1295-4e6a-a16d-46603ac705cb",
-            "url": "https://github.com/MilesCranmer/SymbolicRegression.jl",
-            "rev": "v0.24.1"
+            "version": "=0.24.1"
         },
         "Serialization": {
             "uuid": "9e88b42a-f829-5b0c-bbe9-9e923198166b",
diff --git a/pysr/test/generate_dev_juliapkg.py b/pysr/test/generate_dev_juliapkg.py
index ac4f6b29..6059cfc9 100644
--- a/pysr/test/generate_dev_juliapkg.py
+++ b/pysr/test/generate_dev_juliapkg.py
@@ -9,11 +9,9 @@
 with open(juliapkg_json, "r") as f:
     juliapkg = json.load(f)
 
-juliapkg["packages"]["SymbolicRegression"] = {
-    "uuid": juliapkg["packages"]["SymbolicRegression"]["uuid"],
-    "path": path_to_srjl,
-    "dev": True,
-}
+del juliapkg["packages"]["SymbolicRegression"]["version"]
+juliapkg["packages"]["SymbolicRegression"]["path"] = path_to_srjl
+juliapkg["packages"]["SymbolicRegression"]["dev"] = True
 
 with open(juliapkg_json, "w") as f:
     json.dump(juliapkg, f, indent=4)
diff --git a/pysr/test/test_dev_pysr.dockerfile b/pysr/test/test_dev_pysr.dockerfile
index 3470a7fa..b49df455 100644
--- a/pysr/test/test_dev_pysr.dockerfile
+++ b/pysr/test/test_dev_pysr.dockerfile
@@ -33,12 +33,14 @@ ADD ./pysr/_cli/*.py /pysr/pysr/_cli/
 
 RUN mkdir /pysr/pysr/test
 
+RUN pip3 install --no-cache-dir .
+
 # Now, we create a custom version of SymbolicRegression.jl
 # First, we get the version from juliapkg.json:
-RUN python3 -c 'import json; print(json.load(open("/pysr/pysr/juliapkg.json", "r"))["packages"]["SymbolicRegression"]["rev"])' > /pysr/sr_version
+RUN python3 -c 'import json; print(json.load(open("/pysr/pysr/juliapkg.json", "r"))["packages"]["SymbolicRegression"]["version"])' > /pysr/sr_version
 
-# Remove v from the version:
-RUN cat /pysr/sr_version | sed 's/^v//g' > /pysr/sr_version_processed
+# Remove any = or ^ or ~ from the version:
+RUN cat /pysr/sr_version | sed 's/[\^=~]//g' > /pysr/sr_version_processed
 
 # Now, we check out the version of SymbolicRegression.jl that PySR is using:
 RUN git clone -b "v$(cat /pysr/sr_version_processed)" --single-branch https://github.com/MilesCranmer/SymbolicRegression.jl /srjl
@@ -51,5 +53,5 @@ RUN sed -i 's/module SymbolicRegression/module SymbolicRegression\n__test_functi
 ADD ./pysr/test/generate_dev_juliapkg.py /generate_dev_juliapkg.py
 RUN python3 /generate_dev_juliapkg.py /pysr/pysr/juliapkg.json /srjl
 
-# Install and pre-compile
-RUN pip3 install --no-cache-dir . && python3 -c 'import pysr'
+# Precompile
+RUN python3 -c 'import pysr'