Resin printing never got its open-source moment. That's changing.
Ask anyone why FDM printing matured so quickly and the answer is the same: open source. Marlin and Klipper firmware, open slicers, open hardware designs. Ideas moved freely, users fixed what vendors wouldn't, and the whole category got better faster than any single company could have managed alone.
Resin (MSLA, LCD, DLP, and SLA) printing took a different path. Most printers run closed firmware. Most slicers are proprietary. The file formats your printer reads were never published; they were reverse-engineered by hobbyists, one field at a time. If you have ever wondered why your exposure settings are buried in a binary blob you can't inspect, or why a slicer update suddenly broke compatibility with your machine, that's the reason.
The Open Resin Alliance (ORA) was founded in 2024 to build the open foundation resin printing has been missing. Siraya Tech is an early supporter and financial contributor to ORA through its Open Collective , and this post explains why.
Why a resin manufacturer funds open source software
We make materials, not printers or slicers. So why put money behind a software project?
Because the quality of a resin print is only half chemistry. The other half is how the printer exposes each layer: light intensity, timing, lift and retract profiles, layer-to-layer transitions.
When that side of the equation is hidden inside closed firmware and undocumented file formats, it becomes harder for everyone to get the most out of a material. Users can't see what their printer is actually doing. Material makers can't publish profiles that behave predictably across machines. Small hardware innovators can't build on a shared base.
An open stack changes that. When print parameters are readable, when firmware behavior is documented, and when file formats are public, better resins can actually be used to their full potential. That is directly in our interest and, we think, in the interest of everyone who prints with resin.
Our contribution is modest and ongoing, and we'd rather it be one of many than one of a few. If you print resin and you'd like to see this ecosystem exist, you can back ORA directly on Open Collective .
What the Open Resin Alliance is building
ORA is not a single project. It's a set of pieces designed to work together as an open resin printing stack:
- Orion β an open source printer user interface
- Odyssey β an open source resin printing engine (firmware side)
- DragonFruit β an open source, high-performance resin slicer
Everything is developed in the open on GitHub , with an active community on Discord . The point is not to replace your current setup overnight. It's to give the community a common, modifiable foundation that any person or company can adopt, extend, and contribute to.
DragonFruit: an open source resin slicer worth watching
DragonFruit is the part of the ORA stack most users will touch first. A few things make it interesting:
Open by design. Unlike vendor slicers, its slicing engine and format encoders are public, so support for new printers and file formats can be added by the community rather than waiting on a manufacturer.
A real project file. DragonFruit uses its own scene format (VOXL) that stores models, supports, hollowing, and modifiers, and it can embed that scene directly inside the print file. One file is both printable and re-editable.
Built for high resolution. The slicing engine is written for the 12K-and-beyond generation of printers where file sizes and slicing time become real problems.
If you're comfortable with early-stage software, it's worth trying, and worth reporting issues on. That feedback is how open projects get good.
LUMEN: a print file format designed from scratch
On September 13, 2026, ORA published the LUMEN format specification (v1.0, draft, MIT licensed). It is the native output of DragonFruit and the primary format consumed by Odyssey firmware.
Every mainstream resin format today (CTB, GOO, AFZ, and others) was reverse-engineered from a proprietary ecosystem and carries that legacy: fixed binary layouts, run-length-only compression, obfuscated layer data, and hard limits on resolution. LUMEN starts over.
In plain language, here is what it changes:
Much smaller files for high-resolution prints
A 12K printer produces roughly 75 million pixels per layer. LUMEN compresses layer data using zstd with a shared dictionary across layers, exploiting the fact that adjacent layers are nearly identical. No existing resin format does cross-layer compression.
Settings you can actually read
Exposure, lift, retract, wait times, and material info are stored as structured JSON, not hidden binary fields. You can inspect a print file with ordinary tools.
Per-layer control
Any timing parameter can be overridden for any layer or range of layers, going beyond the bottom/transition/normal model.
Multi-material from the ground up
Each layer can carry multiple independent masks with their own resin and exposure profile, ready for multi-vat hardware that doesn't exist yet.
Portable print profiles
A file can carry a named, versioned profile that compatible firmware can import and reuse.
Encryption that serves the user, not the vendor
Encryption is optional and opt-in, intended for people who need confidentiality, not for locking files to a brand of printer.
Integrity checks
Per-layer hashes allow a printer to verify a file wasn't corrupted in transfer and to resume cleanly after a power loss.
The part we find most exciting as a materials company is an experimental field for the resin's cure curve: penetration depth and critical exposure values that describe how a resin actually polymerizes. Today, exposure settings are found by trial and error. If firmware can eventually compute exposure from resin physics, the data a manufacturer publishes about a material becomes far more useful than a table of per-printer numbers. That is exactly the kind of open standard we want to contribute to.
One honest caveat: LUMEN requires firmware that supports it. Existing printers will keep using CTB, GOO, and the formats they already understand. This is a foundation for the next generation, not a drop-in replacement today.
An open invitation to the resin industry
We'd like to see more of the resin printing world move in this direction. Publish your file formats. Let users read their own print settings. Support open firmware where you can. None of this weakens a good product; it makes the whole category more trustworthy and easier to improve.
Siraya Tech will keep supporting ORA and the projects around it, and we'll keep an eye on how our materials behave on the open stack as it matures.
How to get involved
- Read the spec and follow the projects at openresin.org
- Contribute code, testing, or documentation on GitHub
- Join the community on Discord
- Support the work financially on Open Collective
Open resin printing will only happen if enough people decide it should. We've made our decision. We hope you'll join in.