pub fn has_valid_iban_header(iban: &str) -> bool {
const HEADER_LENGTH: usize = 4;
let characters: Vec<char> = iban.chars().collect();
if characters.len() < HEADER_LENGTH {
return false;
}
let has_country_code = characters[0].is_ascii_uppercase() && characters[1].is_ascii_uppercase();
let has_check_digits = characters[2].is_ascii_digit() && characters[3].is_ascii_digit();
has_country_code && has_check_digits
}
Local reading aid · Legacy, modern and AI-generated code
Unfamiliar code.
Familiar language.
Whether it comes from a legacy application, another team, a migration or an AI: read unfamiliar code beside the language you already know and keep using the engineering judgment you built over years.
UNKNOWN LANGUAGE >>> KNOWN LANGUAGE >>> “NOW I GET IT”
Python·TypeScript·C#·
Java·C++·C·
PHP·Go·Rust·
Kotlin·Ruby·Swift·
VB.NET·Elixir·Zig·
Erlang·JavaScript·Deutsch·English
Scroll / enter the code world
Follow the code
into a language you know.
into a language you know.
Unknown syntax.
Known ways in.
public static bool has_valid_iban_header(string iban)
{
const int HEADER_LENGTH = 4;
List<char> characters = iban.ToCharArray().ToList();
if (characters.Count < HEADER_LENGTH) {
return false;
}
var has_country_code = (characters[0] is >= 'A' and <= 'Z') && (characters[1] is >= 'A' and <= 'Z');
var has_check_digits = (characters[2] is >= '0' and <= '9') && (characters[3] is >= '0' and <= '9');
return has_country_code && has_check_digits;
}from typing import Final
def has_valid_iban_header(iban: str) -> bool:
HEADER_LENGTH: Final[int] = 4
characters: list[str] = list(iban)
if len(characters) < HEADER_LENGTH:
return False
has_country_code = characters[0].isascii() and characters[0].isupper() and (characters[1].isascii() and characters[1].isupper())
has_check_digits = characters[2].isascii() and characters[2].isdigit() and (characters[3].isascii() and characters[3].isdigit())
return has_country_code and has_check_digitsFunction “has_valid_iban_header”:
Parameters:
- “iban”: reference to text
Result: true or false.
Flow:
Constant “HEADER_LENGTH” (non-negative integer) has the value 4.
Set variable “characters” (list of character) to a list of the characters in “iban”.
If (the length of “characters” is less than “HEADER_LENGTH”):
Return false.
Set variable “has_country_code” to (element 0 from “characters” is an ASCII uppercase letter and element 1 from “characters” is an ASCII uppercase letter).
Set variable “has_check_digits” to (element 2 from “characters” is an ASCII digit and element 3 from “characters” is an ASCII digit).
Return (“has_country_code” and “has_check_digits”).
Unknown language · known language · shared understanding
Now I get it.
01 / Put experience back to work
The syntax changed.
The syntax changed.
Your judgment did not.
Production code carries business rules, decisions and edge cases that took years to accumulate. Familiar syntax gives maintainers, reviewers and migration teams a faster way into that knowledge without first mastering every language in the system.
pub fn has_valid_iban_header(iban: &str) -> bool {
const HEADER_LENGTH: usize = 4;
let characters: Vec<char> = iban.chars().collect();
if characters.len() < HEADER_LENGTH {
return false;
}
let has_country_code = characters[0].is_ascii_uppercase() && characters[1].is_ascii_uppercase();
let has_check_digits = characters[2].is_ascii_digit() && characters[3].is_ascii_digit();
has_country_code && has_check_digits
}public static bool has_valid_iban_header(string iban)
{
const int HEADER_LENGTH = 4;
List<char> characters = iban.ToCharArray().ToList();
if (characters.Count < HEADER_LENGTH) {
return false;
}
var has_country_code = (characters[0] is >= 'A' and <= 'Z') && (characters[1] is >= 'A' and <= 'Z');
var has_check_digits = (characters[2] is >= '0' and <= '9') && (characters[3] is >= '0' and <= '9');
return has_country_code && has_check_digits;
}The function rejects an IBAN shorter than four characters. It requires two ASCII uppercase letters for the country code, followed by two ASCII digits, and returns true only when both checks pass.
Maintain legacy systems
Read VB.NET, C, C++ or another inherited codebase through the language your current team knows.
Resolve production issues
Follow conditions, data changes and return paths in an unfamiliar service when time matters.
Recover embedded knowledge
Make years of business logic approachable after developers, vendors or ownership have changed.
Review across languages
Apply your engineering experience across polyglot teams without pretending everyone masters every syntax.
Plan a migration
Understand critical modules and dependencies before rewriting, replacing or retiring an application.
Review AI-generated code
Let AI choose a language while you inspect its visible logic through syntax you can judge confidently.
02 / Language surface
Real languages.
Real languages.
One reading flow.
The translator preserves relevant structure, language-specific boundaries and visible uncertainty across its reading views.
Every supported programming language can be read as every other supported programming language.
From C and C++ to C#, Rust, Java, Python, Go and the BEAM ecosystem.
Readable German and English are first-class targets, not source languages.
03 / Honest boundaries
Useful without
!
↔
✓
Useful without
pretending.
The output is a reading aid — not a port and not a promise that the result compiles or behaves identically.
Translation gaps stay visible
Unsupported constructs become explicit diagnostics or safe placeholders instead of invented behavior.
Formatting carries intent
Meaningful blank lines, comments and multi-line expressions are preserved wherever the target allows it.
Optional problem analysis
Likely flaws can be marked as suggestions without silently changing the source.
04 / Local by design
Your code stays
Your code stays
on your machine.
No cloud translation, no AI request and no telemetry. The bundled translator runs deterministically beside VS Code.
- Local binary
- Read-only previews
- Clear diagnostics
05 / Alpha pricing
Start small.
Start small.
Prove the value.
Private, educational, research, nonprofit and open-source use remains free. Commercial use needs a license.
€0.99/ month
Commercial use, billed monthly and cancellable anytime. Founding price for new customers through 31 October 2026.
- One licensed developer per seat
- Adjustable quantity for teams
- Commercial-use permission
- Alpha updates while active
- No activation or copy protection
€9.99one time
Commercial-use permission from purchase through 31 July 2027.
- One licensed developer per seat
- Adjustable quantity for teams
- Valid through 31 July 2027
- Alpha updates during the term
- No automatic renewal
Secure checkout is provided by Stripe and Link. Choose the quantity to license multiple developers in one purchase. Your voluntary Ko-fi support remains separate from commercial-use permission.
Read the other side