Challenges

Shipping a browser-native Altium library generator meant reverse engineering and stabilizing Altium’s footprint library formats—not just reading public marketing PDFs, but producing byte-level artifacts that open cleanly in modern Altium builds, round-trip through migration, and preserve the parametric links teams expect.

IPC-7351B is precise. Density levels, material conditions, fabrication tolerances, and toe/heel/side fillets all interact. A generator has to apply the same round-off and guard-band rules every time, or two “identical” runs will diverge. We invested in testable math and explicit configuration so “what we meant” is not trapped in a spreadsheet.

The browser is a constraint and a feature. Running a Python pipeline in WebAssembly (Pyodide) avoids shipping a desktop agent, but it demands careful packaging, deterministic builds, and honest progress reporting when CPU and memory are bounded. Everything you configure stays on your machine; the hard part is still making the engine fast enough to feel instant for real projects.

Finally, vendor data drifts. Families age out, part numbers split, and ordering codes change. HLCL encodes families and parameters so updates are data-driven instead of a manual library merge every quarter.