typescript-json-serializer: "Cannot use import statement outside a module" when using versions > 3.0

After microbundle was added to this package, I see the error SyntaxError: Cannot use import statement outside a module whenever I try to use this library. I was able to create a simple reproduction using the code from the README. Compiling and executing this:

import { Serializable, JsonProperty } from 'typescript-json-serializer'

@Serializable()
export class LivingBeing {

    @JsonProperty() id: number;
    constructor(id: number) {
        this.id = id;
        
    }
}

results in this error

/Users/darylwalleck/repos/ts-serializer-test/node_modules/typescript-json-serializer/dist/index.modern.js:1
import"reflect-metadata";function e(){return(e=Object.assign||function(e){for(var t=1;t<arguments.length;t++){var r=arguments[t];for(var a in r)Object.prototype.hasOwnProperty.call(r,a)&&(e[a]=r[a])}return e}).apply(this,arguments)}var t;function r(e){const t=Reflect.getPrototypeOf(e);return t&&t.name?[...r(t),t.name]:[]}function a(r){return(a,n,i)=>{if(void 0===n&&a.prototype){const e=Reflect.getMetadata("design:paramtypes",a)[i];n=function(e){const t=e.toString().replace(/(\/\*[\s\S]*?\*\/|\/\/.*$)/gm,"").replace(/[\r\t\n\v\f]/g,"").replace(/( +)/g," "),r=/(?:this\.)([^\n\r\t\f\v;]+)([\s;])/gm,a=new Map,n=/(?:.*(?:constructor|function).*?(?=\())(?:\()(.+?(?=\)))/m.exec(t);if(!n||!n.length)return a;const i=n[1].replace(/ /g,"").split(",");let o;for(;o=r.exec(t);){const e=o[1].replace(/ /g,"").split("="),t=i.findIndex(t=>t===e[1]);t>-1&&a.set(t,e[0])}return a}(a.prototype.constructor).get(i),a=a.prototype,Reflect.defineMetadata("design:type",e,a,n)}let o={};const s=`api:map:${a.constructor.name}`;Reflect.hasMetadata(s,a)&&(o=Reflect.getMetadata(s,a)),o[n]=function(r,a){if(!a)return{name:r.toString(),isDictionary:!1,isNameOverridden:!1};let n;return n=typeof a===t.String?{name:a,isNameOverridden:!0}:a.name?{name:a.name,isNameOverridden:!0}:a.names&&a.names.length?{names:a.names}:{name:r.toString(),isNameOverridden:!1},n=e({},n,{beforeSerialize:a.beforeSerialize,afterSerialize:a.afterSerialize,beforeDeserialize:a.beforeDeserialize,afterDeserialize:a.afterDeserialize,isDictionary:!!a.isDictionary}),e({},n,a.predicate?{predicate:a.predicate}:{type:a.type})}(n,r),Reflect.defineMetadata(s,o,a)}}function n(e){return t=>{const a=r(t);Reflect.defineMetadata("api:map:serializable",{baseClassNames:a,options:e},t)}}function i(t,r){let a={};return t.forEach(t=>{a=e({},a,Reflect.getMetadata(`api:map:${t}`,r))}),a}function o(r,a){var n;if([null,void 0].includes(r))return r;if(void 0===a)return l(typeof r,r);const s=new a,f=s.constructor.name,{baseClassNames:p,options:u}=null!=(n=Reflect.getMetadata("api:map:serializable",a))?n:{},d=`api:map:${f}`,m=Reflect.hasMetadata(d,s);let y={};return m||p&&p.length?(y=Reflect.getMetadata(d,s),p&&p.length&&(y=e({},i(p,s),y)),Object.keys(y).forEach(e=>{const a=function(e,r,a,n,i){let s;if([null,void 0].includes(n))return n;if("names"in a){const e={};a.names.forEach(t=>e[t]=n[t]),s=e}else if("name"in a&&!a.isNameOverridden&&i){const e=i(a.name);s=n[e]}else s=n[a.name];if([null,void 0].includes(s))return s;const f=Reflect.getMetadata("design:type",e,r),p=!!f.name&&f.name.toLowerCase()===t.Array,u=a.isDictionary,d=a.predicate,m=a.beforeDeserialize,y=a.afterDeserialize;let g=a.type||f;const b=c(g);let v;if(m&&(s=m(s,e)),u){const a={};typeof s!==t.Object?(console.error(`Type '${typeof s}' is not assignable to type 'Dictionary' for property '${r}' in '${e.constructor.name}'.\n`,`Received: ${JSON.stringify(s)}`),v=void 0):(Object.keys(s).forEach(t=>{b||d?(d&&(g=d(s[t],s)),a[t]=o(s[t],g)):a[t]=l(typeof s[t],s[t],r,e.constructor.name)}),v=a)}else if(p){const t=[];Array.isArray(s)?(s.forEach(a=>{b||d?(d&&(g=d(a,s)),t.push(o(a,g))):t.push(l(typeof a,a,r,e.constructor.name))}),v=t):(console.error(`Type '${typeof s}' is not assignable to type 'Array' for property '${r}' in '${e.constructor.name}'.\n`,`Received: ${JSON.stringify(s)}`),v=void 0)}else b||d?(g=d?d(s,n):g,v=o(s,g)):v=l(g.name,s,r,e.constructor.name);return y&&(v=y(v,e)),v}(s,e,y[e],r,null==u?void 0:u.formatPropertyNames);void 0!==a&&(s[e]=a)}),s):s}function s(r,a=!0){var n;if([void 0,null].includes(r)||typeof r!==t.Object)return r;const o=`api:map:${r.constructor.name}`,{baseClassNames:l,options:f}=null!=(n=Reflect.getMetadata("api:map:serializable",r.constructor))?n:{},p=l&&l.length,u=Reflect.hasMetadata(o,r);let d={};if(!u&&!p)return r;d=Reflect.getMetadata(o,r),p&&(d=e({},i(l,r),d));const m={},y=Object.keys(r);return Object.keys(d).forEach(e=>{if(y.includes(e)){const n=d[e],i=n.beforeSerialize,o=n.afterSerialize;let l;i&&(l=r[e],r[e]=i(r[e],r));let p=function(e,r,a,n){const i=e[r],o=Reflect.getMetadata("design:type",e,r),l=!!o.name&&o.name.toLocaleLowerCase()===t.Array,f=a.predicate,p=a.type||o,u=c(p);if(i&&(u||f)){if(l)return i.map(e=>s(e,n));if(a.isDictionary){const e={};return Object.keys(i).forEach(t=>{e[t]=s(i[t],n)}),e}return s(i,n)}return p.name.toLocaleLowerCase()===t.Date&&typeof i===t.Object?i.toISOString():i}(r,e,n,a);if(o&&(p=o(p,r)),r[e]=l||r[e],n.names)n.names.forEach(e=>{(!a||a&&void 0!==p[e])&&(m[e]=p[e])});else if(!a||a&&void 0!==p)if(!n.isNameOverridden&&null!=f&&f.formatPropertyNames){const e=f.formatPropertyNames(n.name);m[e]=p}else m[n.name]=p}}),m}function c(e){return Reflect.hasOwnMetadata("api:map:serializable",e)}function l(e,r,a,n){if(null==e)return r;if(e=e.toLowerCase(),(typeof r).toLowerCase()===e)return r;const i=()=>{console.error(`Type '${typeof r}' is not assignable to type '${e}' for property '${a}' in '${n}'.\n`,`Received: ${JSON.stringify(r)}`)};switch(e){case t.String:const e=r.toString();return"[object Object]"===e?void i():e;case t.Number:const a=+r;return isNaN(a)?void i():a;case t.Boolean:return void i();case t.Date:return isNaN(Date.parse(r))?void i():new Date(r);default:return r}}!function(e){e.Array="array",e.Boolean="boolean",e.Date="date",e.Number="number",e.Object="object",e.String="string"}(t||(t={}));export{a as JsonProperty,n as Serializable,o as deserialize,s as serialize};
^^^^^^

SyntaxError: Cannot use import statement outside a module
    at Object.compileFunction (node:vm:355:18)
    at wrapSafe (node:internal/modules/cjs/loader:1022:15)
    at Module._compile (node:internal/modules/cjs/loader:1056:27)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1121:10)
    at Module.load (node:internal/modules/cjs/loader:972:32)
    at Function.Module._load (node:internal/modules/cjs/loader:813:14)
    at Module.require (node:internal/modules/cjs/loader:996:19)
    at require (node:internal/modules/cjs/helpers:92:18)
    at Object.<anonymous> (/Users/darylwalleck/repos/ts-serializer-test/dist/index.js:13:38)
    at Module._compile (node:internal/modules/cjs/loader:1092:14)

I’m not sure if this is a bug or an issue with my tsconfig.json . Here’s the config I’m using:

{
  "compilerOptions": {
    /* Visit https://aka.ms/tsconfig.json to read more about this file */
    "target": "es2020",
    "module": "commonjs",
    "strict": true,
    "outDir": "./dist",
    "rootDir": "./src",
    "sourceMap": true,
    "esModuleInterop": true,
    "resolveJsonModule": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "declaration": true,
  },
  "include": [
    "src/**/*"
  ]
}

Any feedback would be appreciated. Thanks!