diff --git a/Makefile b/Makefile.in
similarity index 75%
rename from Makefile
rename to Makefile.in
index 19bf062..c16e989 100644
--- a/Makefile
+++ b/Makefile.in
@@ -1,7 +1,7 @@
 C99 = $(CC) -std=c99
-CFLAGS = -g -O3 -DNDEBUG -DDONT_USE_TEST_MAIN
-CPPFLAGS = -g -O3 -fpermissive -DNDEBUG -DDONT_USE_TEST_MAIN
-LDLIBS = -lstdc++ -lz -lm -ltiff
+CFLAGS = -g -O3 -DNDEBUG -DDONT_USE_TEST_MAIN {cflags}
+CPPFLAGS = -g -O3 -fpermissive -DNDEBUG -DDONT_USE_TEST_MAIN {cppflags}
+LDLIBS = -lstdc++ -lz -lm -ltiff {ldflags}
 
 default: bin bin/srtm4 bin/srtm4_which_tile
 
diff --git a/conda-recipe/bld.bat b/conda-recipe/bld.bat
new file mode 100644
index 0000000..cbf296f
--- /dev/null
+++ b/conda-recipe/bld.bat
@@ -0,0 +1 @@
+echo Windows build is not supported
diff --git a/conda-recipe/build.sh b/conda-recipe/build.sh
new file mode 100644
index 0000000..50c8cfb
--- /dev/null
+++ b/conda-recipe/build.sh
@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+python setup.py install --prefix=$PREFIX
diff --git a/conda-recipe/conda_build_config.yaml b/conda-recipe/conda_build_config.yaml
new file mode 100644
index 0000000..e83db0c
--- /dev/null
+++ b/conda-recipe/conda_build_config.yaml
@@ -0,0 +1,12 @@
+python:
+  - 3.6
+  - 3.7
+  - 3.8
+libtiff:
+  - 4.1.0
+
+pin_run_as_build:
+  libtiff:
+    max_pin: x.x
+  python:
+    max_pin: x
diff --git a/conda-recipe/meta.yaml b/conda-recipe/meta.yaml
new file mode 100644
index 0000000..fe6bf98
--- /dev/null
+++ b/conda-recipe/meta.yaml
@@ -0,0 +1,35 @@
+package:
+  name: srtm4
+  version: "1.1.4.dev0"
+
+source:
+  git_rev: sharedlib
+  git_url: https://github.com/yxqd/srtm4
+
+requirements:
+  build:
+    - {{ compiler('cxx') }}  # [linux]
+  host:
+    - python
+    - libtiff
+    - filelock
+    - numpy
+    - requests
+  run:
+    - python
+    - libtiff
+    - filelock
+    - numpy
+    - requests
+
+build:
+  script_env:
+
+test:
+  imports:
+    - srtm4
+
+about:
+  home: 
+  license:
+  license_file:
diff --git a/setup.py b/setup.py
index b0bab4e..fc80922 100644
--- a/setup.py
+++ b/setup.py
@@ -4,6 +4,16 @@
 from setuptools import setup
 from setuptools.command import develop, build_py
 
+def _createMakefile():
+    template = open('Makefile.in').read()
+    cflags = os.environ.get('CFLAGS', '')
+    cppflags = os.environ.get('CPPFLAGS', '')
+    ldflags = os.environ.get('LDFLAGS', '')
+    content = template.format(**locals())
+    open('Makefile', 'wt').write(content)
+    return
+_createMakefile()
+
 
 def readme():
     with open('README.md', 'r', 'utf-8') as f:
diff --git a/srtm4.py b/srtm4.py
index 8b9dd4a..4b43cc5 100644
--- a/srtm4.py
+++ b/srtm4.py
@@ -26,7 +26,9 @@
 if not SRTM_DIR:
     SRTM_DIR = os.path.join(os.path.expanduser('~'), '.srtm')
 
-SRTM_URL = 'http://srtm.csi.cgiar.org/wp-content/uploads/files/srtm_5x5/TIFF'
+SRTM_HTTP_URL = 'http://srtm.csi.cgiar.org/wp-content/uploads/files/srtm_5x5/TIFF'
+SRTM_URL = os.environ.get('SRTM_DATA_URL', SRTM_HTTP_URL)
+if SRTM_URL.endswith('/'): SRTM_URL = SRTM_URL[:-1]
 
 
 def _requests_retry_session(
@@ -51,10 +53,28 @@ def _requests_retry_session(
     session.mount("https://", adapter)
     return session
 
-
 def download(to_file, from_url):
+    '''download a file from the internet
+
+    Args:
+        to_file: path where to store the downloaded file
+        from_url: url of the file to download. could be http or s3
+
+    Raises:
+        RetryError: if the `get` call exceeds the number of retries
+            on 5xx codes
+        ConnectionError: if the `get` call does not return a 200 code
+        NotImplementedError: if the url type is not supported
+    '''
+    if from_url.startswith('http://') or from_url.startswith('https://'):
+        return _download_http(to_file, from_url)
+    if from_url.startswith('s3://'):
+        return _download_s3(to_file, from_url)
+    raise NotImplementedError("{} -> {}".format(from_url, to_file))
+
+def _download_http(to_file, from_url):
     """
-    Download a file from the internet.
+    Download a file from the internet using http.
 
     Args:
         to_file: path where to store the downloaded file
@@ -83,6 +103,11 @@ def download(to_file, from_url):
                 f.write(chunk)
 
 
+def _download_s3(to_file, from_url):
+    import sh
+    sh.aws('s3', 'cp', from_url, to_file)
+    return
+
 def get_srtm_tile(srtm_tile, out_dir):
     """
     Download and unzip an srtm tile from the internet.