diff --git a/.gitignore b/.gitignore
index ff52df5..a5b58bb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -138,4 +138,4 @@ dmypy.json
 cython_debug/
 
 # VS Code configuration
-.vscode
\ No newline at end of file
+.vscode
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 35aef4a..0907e1e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
 # Changelog
 
+## UNRELEASED
+- [#52](https://github.com/crypto-com/pystarport/pull/52) support jsonnet as config language
+
 *Feb 18, 2022*
 
 ## v0.2.4
diff --git a/README.md b/README.md
index 58c628c..3eb1d11 100644
--- a/README.md
+++ b/README.md
@@ -251,6 +251,13 @@ Remember to run `poetry env info` after `poetry install` and update this `python
 }
 ```
 
+## Test
+### Install jsonnet
+More about [jsonnet](https://jsonnet.org).
+```
+make test
+```
+
 
 ## FAQ
 
diff --git a/poetry.lock b/poetry.lock
index 9d14be9..4a306fd 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -195,6 +195,14 @@ python-versions = "*"
 [package.dependencies]
 jsonschema = "*"
 
+[[package]]
+name = "jsonnet"
+version = "0.18.0"
+description = "Python bindings for Jsonnet - The data templating language"
+category = "dev"
+optional = false
+python-versions = "*"
+
 [[package]]
 name = "jsonschema"
 version = "3.2.0"
@@ -511,7 +519,7 @@ six = "*"
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.8"
-content-hash = "c2935da305fc294d57633c7822acd89de94ca2d1ffa322d7fc2d32aeb5ab488b"
+content-hash = "efa956449bf81ed2943e0187e12995e54ca4bdd088295ee4be0be55232be5a70"
 
 [metadata.files]
 atomicwrites = [
@@ -579,6 +587,9 @@ isort = [
 jsonmerge = [
     {file = "jsonmerge-1.8.0.tar.gz", hash = "sha256:a86bfc44f32f6a28b749743df8960a4ce1930666b3b73882513825f845cb9558"},
 ]
+jsonnet = [
+    {file = "jsonnet-0.18.0.tar.gz", hash = "sha256:4ccd13427e9097b6b7d6d38f78f638a55ab8b452a257639e8e9af2178ec235d4"},
+]
 jsonschema = [
     {file = "jsonschema-3.2.0-py2.py3-none-any.whl", hash = "sha256:4e5b3cf8216f577bee9ce139cbe72eca3ea4f292ec60928ff24758ce626cd163"},
     {file = "jsonschema-3.2.0.tar.gz", hash = "sha256:c8a85b28d377cc7737e46e2d9f2b4f44ee3c0e1deac6bf46ddefc7187d30797a"},
diff --git a/pyproject.toml b/pyproject.toml
index b62495a..4e4b5f2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,6 +30,7 @@ deepdiff = "^5.6.0"
 flake8 = "^4.0.1"
 black = "^21.12b0"
 isort = "^5.10.1"
+jsonnet = "^0.18.0"
 
 [tool.poetry.scripts]
 pystarport = "pystarport.cli:main"
diff --git a/pystarport/cluster.py b/pystarport/cluster.py
index 85ce6b3..9a79f82 100644
--- a/pystarport/cluster.py
+++ b/pystarport/cluster.py
@@ -24,7 +24,7 @@
 from . import ports
 from .app import CHAIN, IMAGE, SUPERVISOR_CONFIG_FILE
 from .cosmoscli import ChainCommand, CosmosCLI, ModuleAccount, module_address
-from .expansion import expand_yaml
+from .expansion import expand_jsonnet, expand_yaml
 from .ledger import ZEMU_BUTTON_PORT, ZEMU_HOST
 from .utils import format_doc_string, interact, write_ini
 
@@ -924,7 +924,11 @@ def init_cluster(
     cmd=None,
     gen_compose_file=False,
 ):
-    config = expand_yaml(config_path, dotenv)
+    extension = Path(config_path).suffix
+    if extension == ".jsonnet":
+        config = expand_jsonnet(config_path, dotenv)
+    else:
+        config = expand_yaml(config_path, dotenv)
 
     relayer_config = config.pop("relayer", {})
     for chain_id, cfg in config.items():
diff --git a/pystarport/expansion.py b/pystarport/expansion.py
index 854a57a..d881639 100644
--- a/pystarport/expansion.py
+++ b/pystarport/expansion.py
@@ -1,7 +1,9 @@
+import json
 import os
 from pathlib import Path
 from typing import Any, Mapping, Optional, Text
 
+import _jsonnet
 import jsonmerge
 import yaml
 from dotenv import dotenv_values, load_dotenv
@@ -44,12 +46,34 @@ def _expand(value, variables):
     return "".join([str(atom.resolve(variables)) for atom in atoms])
 
 
+def expand(config, dotenv, path):
+    config_vars = dict(os.environ)  # load system env
+
+    if dotenv is not None:
+        if "dotenv" in config:
+            _ = config.pop("dotenv", {})  # remove dotenv field if exists
+    elif "dotenv" in config:
+        dotenv = config.pop("dotenv", {})  # pop dotenv field if exists
+
+    if dotenv:
+        if not isinstance(dotenv, str):
+            raise ValueError(f"Invalid value passed to dotenv: {dotenv}")
+        env_path = path.parent / dotenv
+        if not env_path.is_file():
+            raise ValueError(
+                f"Dotenv specified in config but not found at path: {env_path}"
+            )
+        config_vars.update(dotenv_values(dotenv_path=env_path))  # type: ignore
+        load_dotenv(dotenv_path=env_path)
+
+    return expand_posix_vars(config, config_vars)
+
+
 def expand_yaml(config_path, dotenv):
     path = Path(config_path)
-    parent = path.parent
     YamlIncludeConstructor.add_to_loader_class(
         loader_class=yaml.FullLoader,
-        base_dir=parent,
+        base_dir=path.parent,
     )
 
     with open(path) as f:
@@ -59,26 +83,12 @@ def expand_yaml(config_path, dotenv):
     if include:
         config = jsonmerge.merge(include, config)
 
-    def expand(dotenv):
-        if not isinstance(dotenv, str):
-            raise ValueError(f"Invalid value passed to dotenv: {dotenv}")
-        config_vars = dict(os.environ)  # load system env
-        env_path = parent.joinpath(dotenv)
-        if not env_path.is_file():
-            raise ValueError(
-                f"Dotenv specified in config but not found at path: {env_path}"
-            )
-        config_vars.update(dotenv_values(dotenv_path=env_path))  # type: ignore
-        load_dotenv(dotenv_path=env_path)
-        return expand_posix_vars(config, config_vars)
+    config = expand(config, dotenv, path)
+    return config
 
-    if dotenv is not None:
-        if "dotenv" in config:
-            _ = config.pop("dotenv", {})  # remove dotenv field if exists
-        dotenv_path = dotenv
-        config = expand(dotenv_path)
-    elif "dotenv" in config:
-        dotenv_path = config.pop("dotenv", {})  # pop dotenv field if exists
-        config = expand(dotenv_path)
 
+def expand_jsonnet(config_path, dotenv):
+    path = Path(config_path)
+    config = json.loads(_jsonnet.evaluate_file(str(config_path)))
+    config = expand(config, dotenv, path)
     return config
diff --git a/pystarport/tests/test_expansion/base.jsonnet b/pystarport/tests/test_expansion/base.jsonnet
new file mode 100644
index 0000000..55f02be
--- /dev/null
+++ b/pystarport/tests/test_expansion/base.jsonnet
@@ -0,0 +1 @@
+import './default.jsonnet'
diff --git a/pystarport/tests/test_expansion/base_yaml.jsonnet b/pystarport/tests/test_expansion/base_yaml.jsonnet
new file mode 100644
index 0000000..63ba1e3
--- /dev/null
+++ b/pystarport/tests/test_expansion/base_yaml.jsonnet
@@ -0,0 +1 @@
+std.manifestYamlDoc(import './base.jsonnet', true, false)
diff --git a/pystarport/tests/test_expansion/cronos_has_dotenv.jsonnet b/pystarport/tests/test_expansion/cronos_has_dotenv.jsonnet
new file mode 100644
index 0000000..9b37245
--- /dev/null
+++ b/pystarport/tests/test_expansion/cronos_has_dotenv.jsonnet
@@ -0,0 +1,40 @@
+local config = import './default.jsonnet';
+local Utils = import 'utils.jsonnet';
+
+config {
+  dotenv+: 'dotenv',
+  'cronos_777-1'+: {
+    validators: [
+      Utils.validator('${VALIDATOR1_MNEMONIC}'),
+      Utils.validator('${VALIDATOR2_MNEMONIC}'),
+    ],
+    accounts: [
+      Utils.account(
+        'community',
+        '10000000000000000000000basetcro',
+        '${COMMUNITY_MNEMONIC}',
+      ),
+      Utils.account(
+        'signer1',
+        '20000000000000000000000basetcro',
+        '${SIGNER1_MNEMONIC}',
+      ),
+      Utils.account(
+        'signer2',
+        '30000000000000000000000basetcro',
+        '${SIGNER2_MNEMONIC}',
+      ),
+    ],
+    genesis+: {
+      app_state+: {
+        cronos: {
+          params: {
+            cronos_admin: '${CRONOS_ADMIN}',
+            enable_auto_deployment: true,
+            ibc_cro_denom: '${IBC_CRO_DENOM}',
+          },
+        },
+      },
+    },
+  },
+}
diff --git a/pystarport/tests/test_expansion/cronos_has_dotenv_yaml.jsonnet b/pystarport/tests/test_expansion/cronos_has_dotenv_yaml.jsonnet
new file mode 100644
index 0000000..beb7aa0
--- /dev/null
+++ b/pystarport/tests/test_expansion/cronos_has_dotenv_yaml.jsonnet
@@ -0,0 +1 @@
+std.manifestYamlDoc(import './cronos_has_dotenv.jsonnet', true, false)
diff --git a/pystarport/tests/test_expansion/cronos_has_posix_no_dotenv.jsonnet b/pystarport/tests/test_expansion/cronos_has_posix_no_dotenv.jsonnet
new file mode 100644
index 0000000..be53a5b
--- /dev/null
+++ b/pystarport/tests/test_expansion/cronos_has_posix_no_dotenv.jsonnet
@@ -0,0 +1,39 @@
+local config = import './default.jsonnet';
+local Utils = import 'utils.jsonnet';
+
+config {
+  'cronos_777-1'+: {
+    validators: [
+      Utils.validator('${VALIDATOR1_MNEMONIC}'),
+      Utils.validator('${VALIDATOR2_MNEMONIC}'),
+    ],
+    accounts: [
+      Utils.account(
+        'community',
+        '10000000000000000000000basetcro',
+        '${COMMUNITY_MNEMONIC}',
+      ),
+      Utils.account(
+        'signer1',
+        '20000000000000000000000basetcro',
+        '${SIGNER1_MNEMONIC}',
+      ),
+      Utils.account(
+        'signer2',
+        '30000000000000000000000basetcro',
+        '${SIGNER2_MNEMONIC}',
+      ),
+    ],
+    genesis+: {
+      app_state+: {
+        cronos: {
+          params: {
+            cronos_admin: '${CRONOS_ADMIN}',
+            enable_auto_deployment: true,
+            ibc_cro_denom: '${IBC_CRO_DENOM}',
+          },
+        },
+      },
+    },
+  },
+}
diff --git a/pystarport/tests/test_expansion/cronos_has_posix_no_dotenv_yaml.jsonnet b/pystarport/tests/test_expansion/cronos_has_posix_no_dotenv_yaml.jsonnet
new file mode 100644
index 0000000..4a8288a
--- /dev/null
+++ b/pystarport/tests/test_expansion/cronos_has_posix_no_dotenv_yaml.jsonnet
@@ -0,0 +1 @@
+std.manifestYamlDoc(import './cronos_has_posix_no_dotenv.jsonnet', true, false)
diff --git a/pystarport/tests/test_expansion/cronos_no_dotenv.jsonnet b/pystarport/tests/test_expansion/cronos_no_dotenv.jsonnet
new file mode 100644
index 0000000..55f02be
--- /dev/null
+++ b/pystarport/tests/test_expansion/cronos_no_dotenv.jsonnet
@@ -0,0 +1 @@
+import './default.jsonnet'
diff --git a/pystarport/tests/test_expansion/cronos_no_dotenv_yaml.jsonnet b/pystarport/tests/test_expansion/cronos_no_dotenv_yaml.jsonnet
new file mode 100644
index 0000000..5467581
--- /dev/null
+++ b/pystarport/tests/test_expansion/cronos_no_dotenv_yaml.jsonnet
@@ -0,0 +1 @@
+std.manifestYamlDoc(import './cronos_no_dotenv.jsonnet', true, false)
diff --git a/pystarport/tests/test_expansion/default.jsonnet b/pystarport/tests/test_expansion/default.jsonnet
new file mode 100644
index 0000000..7f79248
--- /dev/null
+++ b/pystarport/tests/test_expansion/default.jsonnet
@@ -0,0 +1,78 @@
+local Utils = import "utils.jsonnet";
+
+{
+  'cronos_777-1': {
+    cmd: 'cronosd',
+    'start-flags': '--trace',
+    'app-config': {
+      'minimum-gas-prices': '5000000000000basetcro',
+      'json-rpc': {
+        address: '0.0.0.0:{EVMRPC_PORT}',
+        'ws-address': '0.0.0.0:{EVMRPC_PORT_WS}',
+      },
+    },
+    validators: [
+      Utils.validator('visit craft resemble online window solution west chuckle music diesel vital settle comic tribe project blame bulb armed flower region sausage mercy arrive release'),
+      Utils.validator('direct travel shrug hand twice agent sail sell jump phone velvet pilot mango charge usual multiply orient garment bleak virtual action mention panda vast'),
+    ],
+    accounts: [
+      Utils.account(
+        'community',
+        '10000000000000000000000basetcro',
+        'notable error gospel wave pair ugly measure elite toddler cost various fly make eye ketchup despair slab throw tribe swarm word fruit into inmate',
+      ),
+      Utils.account(
+        'signer1',
+        '20000000000000000000000basetcro',
+        'shed crumble dismiss loyal latin million oblige gesture shrug still oxygen custom remove ribbon disorder palace addict again blanket sad flock consider obey popular',
+      ),
+      Utils.account(
+        'signer2',
+        '30000000000000000000000basetcro',
+        'night renew tonight dinner shaft scheme domain oppose echo summer broccoli agent face guitar surface belt veteran siren poem alcohol menu custom crunch index',
+      ),
+    ],
+    genesis: {
+      consensus_params: {
+        block: {
+          max_bytes: '1048576',
+          max_gas: '81500000',
+        },
+      },
+      app_state: {
+        evm: {
+          params: {
+            evm_denom: 'basetcro',
+          },
+        },
+        cronos: {
+          params: {
+            cronos_admin: 'crc12luku6uxehhak02py4rcz65zu0swh7wjsrw0pp',
+            enable_auto_deployment: true,
+            ibc_cro_denom: 'ibc/6411AE2ADA1E73DB59DB151A8988F9B7D5E7E233D8414DB6817F8F1A01611F86',
+          },
+        },
+        gov: {
+          voting_params: {
+            voting_period: '10s',
+          },
+          deposit_params: {
+            max_deposit_period: '10s',
+            min_deposit: [
+              {
+                denom: 'basetcro',
+                amount: '1',
+              },
+            ],
+          },
+        },
+        transfer: {
+          params: {
+            receive_enabled: true,
+            send_enabled: true,
+          },
+        },
+      },
+    },
+  },
+}
diff --git a/pystarport/tests/test_expansion/generate-test-yamls b/pystarport/tests/test_expansion/generate-test-yamls
new file mode 100755
index 0000000..4c15a39
--- /dev/null
+++ b/pystarport/tests/test_expansion/generate-test-yamls
@@ -0,0 +1,15 @@
+#!/bin/bash
+
+set +e
+cd "$(dirname "$0")"
+
+# explicitly set a short TMPDIR to prevent path too long issue on macosx
+export TMPDIR=/tmp
+
+files=("base" "cronos_has_dotenv" "cronos_has_posix_no_dotenv" "cronos_no_dotenv")
+length=${#files[@]}
+for (( i=0; i<${length}; i++ ))
+do
+    echo "generating "${files[$i]}".yaml"
+    jsonnet -S ${files[$i]}"_yaml".jsonnet -o ${files[$i]}.yaml
+done
diff --git a/pystarport/tests/test_expansion/test_expansion.py b/pystarport/tests/test_expansion/test_expansion.py
index 234c14b..0f408d1 100644
--- a/pystarport/tests/test_expansion/test_expansion.py
+++ b/pystarport/tests/test_expansion/test_expansion.py
@@ -1,34 +1,45 @@
 import os
 from pathlib import Path
 
+import pytest
 import yaml
 from deepdiff import DeepDiff
 
-from pystarport.expansion import expand_yaml
+from pystarport.expansion import expand_jsonnet, expand_yaml
 
 
-def test_expansion():
-    parent = Path(__file__).parent
-    base = parent / "base.yaml"
-    cronos_has_dotenv = parent / "cronos_has_dotenv.yaml"
-    cronos_no_dotenv = parent / "cronos_no_dotenv.yaml"
-    cronos_has_posix_no_dotenv = parent / "cronos_has_posix_no_dotenv.yaml"
+def _get_base_config():
+    return yaml.safe_load(open(Path(__file__).parent / "base.yaml"))
+
 
-    baseConfig = yaml.safe_load(open(base))
+@pytest.mark.parametrize(
+    "type, func",
+    [(".yaml", expand_yaml), (".jsonnet", expand_jsonnet)],
+)
+def test_expansion(type, func):
+    parent = Path(__file__).parent
+    cronos_has_dotenv = parent / ("cronos_has_dotenv" + type)
+    cronos_no_dotenv = parent / ("cronos_no_dotenv" + type)
+    cronos_has_posix_no_dotenv = parent / ("cronos_no_dotenv" + type)
+    baseConfig = _get_base_config()
     # `expand_yaml` is backward compatible, not expanded, and no diff
-    assert baseConfig == expand_yaml(cronos_no_dotenv, None)
+    config = func(cronos_no_dotenv, None)
+    assert baseConfig == config
 
     # `expand_yaml` is expanded but no diff
+    config = func(cronos_has_dotenv, None)
     assert not DeepDiff(
         baseConfig,
-        expand_yaml(cronos_has_dotenv, None),
+        config,
         ignore_order=True,
     )
 
     # overriding dotenv with relative path is expanded and has diff)
+    dotenv = "dotenv1"
+    config = func(cronos_has_dotenv, dotenv)
     assert DeepDiff(
         baseConfig,
-        expand_yaml(cronos_has_dotenv, "dotenv1"),
+        config,
         ignore_order=True,
     ) == {
         "values_changed": {
@@ -42,9 +53,11 @@ def test_expansion():
     }
 
     # overriding dotenv with absolute path is expanded and has diff
+    dotenv = os.path.abspath("test_expansion/dotenv1")
+    config = func(cronos_has_dotenv, dotenv)
     assert DeepDiff(
         baseConfig,
-        expand_yaml(cronos_has_dotenv, os.path.abspath("test_expansion/dotenv1")),
+        config,
         ignore_order=True,
     ) == {
         "values_changed": {
@@ -58,10 +71,10 @@ def test_expansion():
     }
 
     # overriding dotenv with absolute path is expanded and no diff
+    dotenv = os.path.abspath("test_expansion/dotenv")
+    config = func(cronos_has_posix_no_dotenv, dotenv)
     assert not DeepDiff(
         baseConfig,
-        expand_yaml(
-            cronos_has_posix_no_dotenv, os.path.abspath("test_expansion/dotenv")
-        ),
+        config,
         ignore_order=True,
     )
diff --git a/pystarport/tests/test_expansion/utils.jsonnet b/pystarport/tests/test_expansion/utils.jsonnet
new file mode 100644
index 0000000..c844e4e
--- /dev/null
+++ b/pystarport/tests/test_expansion/utils.jsonnet
@@ -0,0 +1,12 @@
+{
+  validator(mnemonic):: {
+    coins: '1000000000000000000stake,10000000000000000000000basetcro',
+    staked: '1000000000000000000stake',
+    mnemonic: mnemonic,
+  },
+  account(name, coins, mnemonic):: {
+    name: name,
+    coins: coins,
+    mnemonic: mnemonic,
+  },
+}