diff --git a/generate-modulemd.py b/generate-modulemd.py
new file mode 100755
index 0000000..572532c
--- /dev/null
+++ b/generate-modulemd.py
@@ -0,0 +1,267 @@
+#!/usr/bin/python3
+# Author: Mikolaj Izdebski <mizdebsk@redhat.com>
+
+import os
+import re
+import logging
+import koji
+import hawkey
+
+from koschei import config
+from koschei.backend import koji_util, repo_util, depsolve, repo_cache
+
+log = logging.getLogger('')
+
+bootstrap = False
+
+api = ['maven']
+profiles = {'default': ['maven']}
+includes = ['python-lxml', 'byaccj']
+excludes = ['java-1.7.0-openjdk', 'java-1.8.0-openjdk']
+
+macros = {
+    '_with_xmvn_javadoc': 1,
+    '_without_asciidoc': 1,
+    '_without_avalon': 1,
+    '_without_bouncycastle': 1,
+    '_without_cython': 1,
+    '_without_dafsa': 1,
+    '_without_desktop': 1,
+    '_without_doxygen': 1,
+    '_without_dtd': 1,
+    '_without_eclipse': 1,
+    '_without_ehcache': 1,
+    '_without_emacs': 1,
+    '_without_equinox': 1,
+    '_without_fop': 1,
+    '_without_ftp': 1,
+    '_without_gradle': 1,
+    '_without_groovy': 1,
+    '_without_hadoop': 1,
+    '_without_hsqldb': 1,
+    '_without_itext': 1,
+    '_without_jmh': 1,
+    '_without_jna': 1,
+    '_without_jpa': 1,
+    '_without_logback': 1,
+    '_without_markdown': 1,
+    '_without_memcached': 1,
+    '_without_memoryfilesystem': 1,
+    '_without_obr': 1,
+    '_without_python': 1,
+    '_without_reporting': 1,
+    '_without_scm': 1,
+    '_without_snappy': 1,
+    '_without_spring': 1,
+    '_without_ssh': 1,
+    '_without_testlib': 1,
+}
+
+config.load_config(['koschei.cfg'], ignore_env=True)
+ks = koji_util.KojiSession()
+
+tag_name = config.get_koji_config('primary', 'tag_name')
+repo_id = ks.getRepo(tag_name, state=koji.REPO_READY)['id']
+repo_descriptor = repo_util.KojiRepoDescriptor('primary', tag_name, repo_id)
+
+
+# Parse RPM name - split it into NVRA dict
+def parse_nvra(str):
+    m = re.match(r'^(.+)-([^-]+)-([^-]+)\.([^-.]+).rpm$', str)
+    return {'name': m.group(1), 'version': m.group(2),
+            'release': m.group(3), 'arch': m.group(4)}
+
+
+# Get RPM name
+def name(rpm):
+    return parse_nvra(rpm)['name']
+
+
+# Try to heuristically guess whether given hawkey package is Java package and
+# should be part of maven module, or not. Explicit includes and excludes always
+# have preference over heuristic.
+def is_maven_pkg(pkg):
+    if name(pkg.sourcerpm) in includes:
+        return True
+    if name(pkg.sourcerpm) in excludes:
+        return False
+    for file in pkg.files:
+        if file.startswith('/usr/share/maven-metadata/'):
+            return True
+        if file.startswith('/usr/share/java/'):
+            return True
+        if file.startswith('/usr/lib/java/'):
+            return True
+    return False
+
+
+# Simulate installation of given dependencies.
+def resolve_deps(sack, deps):
+    log.info('Resolving deps...')
+    resolved, problems, installs = depsolve.run_goal(sack, deps, [])
+    if not resolved:
+        installs = set()
+        for pkg in deps:
+            resolved, problems, pkg_installs = \
+                depsolve.run_goal(sack, [pkg], [])
+            if resolved:
+                installs.update(pkg_installs)
+            else:
+                log.warning('Dependency problems for {}:\n{}'
+                            .format(pkg, '\n'.join(problems)))
+    java = {pkg.sourcerpm for pkg in installs if is_maven_pkg(pkg)}
+    return java, set(installs)
+
+
+# Input: BuildRequires string
+# Output: matched hawkey packages
+def resolve_builddep(sack, br):
+    return depsolve._get_builddep_selector(sack, br).matches()
+
+
+# Input: hawkey reldep
+# Output: matched hawkey packages
+def resolve_reldep(sack, reldep):
+    return hawkey.Query(sack).filter(provides=reldep)
+
+
+# Get build-requires of given SRPMs from Koji.
+def get_build_requires(srpms):
+    log.info('Getting build-requires from Koji...')
+    return koji_util.get_rpm_requires(ks, [parse_nvra(srpm) for srpm in srpms])
+
+
+# Do the main work. Recursively resolve requires and build-requires, starting
+# from initial list of seed packages.
+def work(sack):
+    srpms_done = set()
+    br_map = {}
+    srpms_todo, pkgs = resolve_deps(sack, api)
+
+    def add(map, key, val):
+        _set = map.get(key, set())
+        map[key] = _set
+        _set.add(val)
+
+    while srpms_todo:
+        log.info('Round: {} packages'.format(len(srpms_todo)))
+        srpms_todo = {srpm for srpm in srpms_todo
+                      if name(srpm) not in excludes}
+        srpms_done |= srpms_todo
+        combined_br = set()
+        for srpm, build_requires in zip(srpms_todo, get_build_requires(srpms_todo)):
+            combined_br |= set(build_requires)
+            for br in build_requires:
+                add(br_map, br, srpm)
+        java, all = resolve_deps(sack, combined_br)
+        srpms_todo |= java
+        srpms_todo -= srpms_done
+        pkgs |= all
+
+    def our(pkgs):
+        return (pkg for pkg in pkgs if pkg.sourcerpm in srpms_done)
+
+    api_srpms = {pkg.sourcerpm for pkg in pkgs if pkg.name in api}
+
+    build_deps = {}
+    for br, srpms in br_map.items():
+        for dep in our(resolve_builddep(sack, br)):
+            for srpm in srpms:
+                add(build_deps, dep.sourcerpm, srpm)
+
+    runtime_deps = {}
+    for pkg in our(pkgs):
+        for reldep in pkg.requires:
+            for dep in resolve_reldep(sack, reldep):
+                if dep.sourcerpm != pkg.sourcerpm:
+                    add(runtime_deps, dep.sourcerpm, pkg.sourcerpm)
+
+    yaml = list()
+    yaml.append('---')
+    yaml.append('document: modulemd')
+    yaml.append('version: 1')
+    yaml.append('data:')
+    yaml.append('    summary: Java project management and project comprehension tool')
+    yaml.append('    description: >-')
+    yaml.append('        Maven is a software project management and comprehension tool.')
+    yaml.append('        Based on the concept of a project object model (POM), Maven')
+    yaml.append('        can manage a project\'s build, reporting and documentation from')
+    yaml.append('        a central piece of information.')
+    yaml.append('    license:')
+    yaml.append('        module:')
+    yaml.append('            - MIT')
+    yaml.append('    dependencies:')
+    yaml.append('        buildrequires:')
+    if bootstrap:
+        yaml.append('            bootstrap: master')
+    else:
+        yaml.append('            maven: master')
+        yaml.append('            java: master')
+        yaml.append('            platform: master')
+        yaml.append('            # R of hawtjni')
+        yaml.append('            autotools: master')
+        yaml.append('            # BR of python-lxml')
+        yaml.append('            python2: master')
+        yaml.append('            python3: master')
+        yaml.append('            # BR of xml-stylebook')
+        yaml.append('            fonts: master')
+    yaml.append('        requires:')
+    yaml.append('            java: master')
+    yaml.append('            platform: master')
+    yaml.append('    profiles:')
+    for k, v in profiles.items():
+        yaml.append('        {}:'.format(k))
+        yaml.append('            rpms:')
+        for p in sorted(v):
+            yaml.append('                - {}'.format(p))
+    yaml.append('    api:')
+    yaml.append('        rpms:')
+    for p in sorted(api):
+        yaml.append('            - {}'.format(p))
+    yaml.append('    filter:')
+    yaml.append('        rpms:')
+    yaml.append('            - python2-lxml')
+    yaml.append('    buildopts:')
+    yaml.append('        rpms:')
+    yaml.append('            macros: |')
+    for k, v in macros.items():
+        yaml.append('                %{} {}'.format(k, v))
+    yaml.append('    components:')
+    yaml.append('        rpms:')
+
+    def format_rationale(type, srpms):
+        rt = '                    {} of'.format(type)
+        for srpm in sorted(srpms):
+            r = name(srpm)
+            if len(rt + ' ' + r + ',') >= 80:
+                yaml.append(rt)
+                rt = '                        '
+            rt += ' ' + r + ','
+        rt = rt[:-1] + '.'
+        yaml.append(rt)
+
+    for srpm in sorted(srpms_done):
+        yaml.append('            {}:'.format(name(srpm)))
+        yaml.append('                rationale: >')
+        if srpm in api_srpms:
+            yaml.append('                    Module API.')
+        if srpm in runtime_deps:
+            format_rationale('Runtime dependency', runtime_deps[srpm])
+        if srpm in build_deps:
+            format_rationale('Build dependency', build_deps[srpm])
+
+    with open('maven.yaml', 'w') as f:
+        for line in yaml:
+            print(line, file=f)
+
+
+def main():
+    if not os.path.exists('/tmp/maven-modulemd-gen/repodata'):
+        os.makedirs('/tmp/maven-modulemd-gen/repodata')
+    log.info('Loading sack...')
+    with repo_cache.RepoCache().get_sack(repo_descriptor) as sack:
+        work(sack)
+
+
+if __name__ == '__main__':
+    main()
diff --git a/koschei.cfg b/koschei.cfg
new file mode 100644
index 0000000..b87ce9a
--- /dev/null
+++ b/koschei.cfg
@@ -0,0 +1,34 @@
+# -*- python -*-
+# vim: ft=python
+config = {
+    "koji_config": {
+        "server": "https://koji.lbzip2.org/kojihub",
+        "topurl": "https://koji.lbzip2.org/kojifiles",
+        "multicall_chunk_size": 1000,
+        "tag_name": "maven",
+    },
+    "dependency": {
+        "repo_arch": "x86_64",
+        "resolve_for_arch": "x86_64",
+        "ignore_weak_deps": True,
+        "cache_l2_capacity": 2,
+    },
+    "directories": {
+        "cachedir": "/tmp/maven-modulemd-gen",
+    },
+    "logging": {
+        "version": 1,
+        "loggers": {
+            "": {
+                "level": "INFO",
+                "handlers": ["stderr"],
+            },
+        },
+        "handlers": {
+            "stderr": {
+                "class": "logging.StreamHandler",
+                "stream": "ext://sys.stderr"
+            },
+        },
+    },
+}