error in production, not in dev

There is an error in the production minified version of the app

production mode error

next build
next start

Loading index.tsx in browser produces error

index-71f057e0ed448a3d.js:1 SyntaxError: Unexpected token '{'
    at eval (eval at e.exports.runInThisContext (381-ece9bef8390c6cd3.js:1:19120), <anonymous>:3:13)
    at e.exports.runInThisContext (381-ece9bef8390c6cd3.js:1:19167)
    at d.compile (381-ece9bef8390c6cd3.js:1:5179)
    at d.parse (381-ece9bef8390c6cd3.js:1:5910)
    at P (381-ece9bef8390c6cd3.js:1:25743)
    at ec.readBlockHeader (381-ece9bef8390c6cd3.js:1:53537)
    at async ec.readBlock (381-ece9bef8390c6cd3.js:1:58061)
    at async ec.getContainerById (381-ece9bef8390c6cd3.js:1:52554)
    at async ec.getSamHeader (381-ece9bef8390c6cd3.js:1:51696)

comes from a chunk being eval'd

This is not a super-stripped down reproducible use case, but comes from our modules @gmod/cram https://github.com/GMOD/cram-js/ specifically this file https://github.com/GMOD/cram-js/blob/master/src/cramFile/file.ts

the chunk that fails to eval is below here, specifically "formatter(e){let t"

(function(buffer, constructorFn, Long) { if (!Buffer.isBuffer(buffer)) {
throw new Error("argument buffer is not a Buffer object");
}
var offset = 0;
var vars = {};
vars.compressionMethod = buffer.readUInt8(offset);
offset += 1;
vars.compressionMethod = (formatter(e){let t=["raw","gzip","bzip2","lzma","rans","rans4x16","arith","fqzcomp","tok3"][e];if(!t)throw Error(`compression method number ${e} not implemented`);return t}).call(this, vars.compressionMethod);
vars.contentType = buffer.readUInt8(offset);
offset += 1;
vars.contentType = (formatter(e){let t=["FILE_HEADER","COMPRESSION_HEADER","MAPPED_SLICE_HEADER","UNMAPPED_SLICE_HEADER","EXTERNAL_DATA","CORE_DATA"][e];if(!t)throw Error(`invalid block content type id ${e}`);return t}).call(this, vars.contentType);

    var $tmp0 = buffer[offset];
    if ($tmp0 < 0x80) {
      vars.contentId = $tmp0;
      offset += 1;
    } else if ($tmp0 < 0xc0) {
      vars.contentId = (($tmp0<<8) | buffer[offset+1]) & 0x3fff;
      offset += 2;
    } else if ($tmp0 < 0xe0) {
      vars.contentId = (($tmp0<<16) | (buffer[offset+1]<< 8) |  buffer[offset+2]) & 0x1fffff;
      offset += 3;
    } else if ($tmp0 < 0xf0) {
      vars.contentId = (($tmp0<<24) | (buffer[offset+1]<<16) | (buffer[offset+2]<<8) | buffer[offset+3]) & 0x0fffffff;
      offset += 4
    } else {
      vars.contentId = (($tmp0 & 0x0f)<<28) | (buffer[offset+1]<<20) | (buffer[offset+2]<<12) | (buffer[offset+3]<<4) | (buffer[offset+4] & 0x0f);
      // x=((0xff & 0x0f)<<28) | (0xff<<20) | (0xff<<12) | (0xff<<4) | (0x0f & 0x0f);
      // TODO *val_p = uv < 0x80000000UL ? uv : -((int32_t) (0xffffffffUL - uv)) - 1;
      offset += 5
    }


    var $tmp1 = buffer[offset];
    if ($tmp1 < 0x80) {
      vars.compressedSize = $tmp1;
      offset += 1;
    } else if ($tmp1 < 0xc0) {
      vars.compressedSize = (($tmp1<<8) | buffer[offset+1]) & 0x3fff;
      offset += 2;
    } else if ($tmp1 < 0xe0) {
      vars.compressedSize = (($tmp1<<16) | (buffer[offset+1]<< 8) |  buffer[offset+2]) & 0x1fffff;
      offset += 3;
    } else if ($tmp1 < 0xf0) {
      vars.compressedSize = (($tmp1<<24) | (buffer[offset+1]<<16) | (buffer[offset+2]<<8) | buffer[offset+3]) & 0x0fffffff;
      offset += 4
    } else {
      vars.compressedSize = (($tmp1 & 0x0f)<<28) | (buffer[offset+1]<<20) | (buffer[offset+2]<<12) | (buffer[offset+3]<<4) | (buffer[offset+4] & 0x0f);
      // x=((0xff & 0x0f)<<28) | (0xff<<20) | (0xff<<12) | (0xff<<4) | (0x0f & 0x0f);
      // TODO *val_p = uv < 0x80000000UL ? uv : -((int32_t) (0xffffffffUL - uv)) - 1;
      offset += 5
    }


    var $tmp2 = buffer[offset];
    if ($tmp2 < 0x80) {
      vars.uncompressedSize = $tmp2;
      offset += 1;
    } else if ($tmp2 < 0xc0) {
      vars.uncompressedSize = (($tmp2<<8) | buffer[offset+1]) & 0x3fff;
      offset += 2;
    } else if ($tmp2 < 0xe0) {
      vars.uncompressedSize = (($tmp2<<16) | (buffer[offset+1]<< 8) |  buffer[offset+2]) & 0x1fffff;
      offset += 3;
    } else if ($tmp2 < 0xf0) {
      vars.uncompressedSize = (($tmp2<<24) | (buffer[offset+1]<<16) | (buffer[offset+2]<<8) | buffer[offset+3]) & 0x0fffffff;
      offset += 4
    } else {
      vars.uncompressedSize = (($tmp2 & 0x0f)<<28) | (buffer[offset+1]<<20) | (buffer[offset+2]<<12) | (buffer[offset+3]<<4) | (buffer[offset+4] & 0x0f);
      // x=((0xff & 0x0f)<<28) | (0xff<<20) | (0xff<<12) | (0xff<<4) | (0x0f & 0x0f);
      // TODO *val_p = uv < 0x80000000UL ? uv : -((int32_t) (0xffffffffUL - uv)) - 1;
      offset += 5
    }

return { offset: offset, result: vars };
return { offset: offset, result: vars };
 })

can see in https://esprima.org/demo/validate.html that this is syntactically invalid

dev mode works

next dev