Helm3 workaround for pulumi, see https://github.com/pulumi/pulumi-kubernetes/issues/1335. Doens't support arrays and requires manual escaping / marshaling.

helm3.ts

import * as child_process from "child_process";
import * as pulumi from "@pulumi/pulumi";
import * as k8s from "@pulumi/kubernetes";

const SPAWN_PROCESS_BUFFER_SIZE = 104857600;

export const repos = {
  stable: "https://kubernetes-charts.storage.googleapis.com",
  prometheus: "https://prometheus-community.github.io/helm-charts",
  jetstack: "https://charts.jetstack.io",
  ingress: "https://kubernetes.github.io/ingress-nginx",
  banzaicloud: "https://kubernetes-charts.banzaicloud.com"
};

export interface Helm3Args {
  repos?: { [keyof: string]: string },
  fetchOpts: {
    repo: string
  }
  version: string,
  values?: pulumi.Inputs,
  namespace?: pulumi.Input<string>,
  chart: string
}

function jsonToHelmSetValues(values: { [keyof: string]: any }): string[] {
  // TODO: arrays
  return Object.keys(values).map(key => {
    const value = values[key];
    if (value instanceof Object) {
      const nextValues = jsonToHelmSetValues(value);
      return nextValues.map(v => `${key}.${v.toString()}`)
    } else {
      return [`${key}=${value.toString()}`];
    }
  }).flat();
}

export function helm3(name: string, args: Helm3Args, opts?: pulumi.ComponentResourceOptions) {
  const setArgs =
    jsonToHelmSetValues(args.values || {})
      .map(value => `--set ${value}`)
      .join(" ");

  const helmArgs = [
    `--version ${args.version}`,
    `--namespace ${args.namespace || 'default'}`,
    `--repo ${args.fetchOpts.repo}`,
    setArgs
  ].join(" ");

  const helmCmd = `helm template ${name} ${args.chart} ${helmArgs}`;
  console.log(helmCmd)
  const rendered = child_process.execSync(helmCmd, {
    maxBuffer: SPAWN_PROCESS_BUFFER_SIZE
  }).toString();

  return new k8s.yaml.ConfigGroup(name, {
    yaml: rendered,
  }, opts);

}