🎉 v0.11.5-beta Released: User Feedback Sprint Complete!

[kolkov]

Release Date: November 4, 2025
Tag: v0.11.5-beta
Sprint Duration: 12 hours (estimated 3-4 weeks) - 30x faster! 🚀

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🌟 Major Milestone: First Production User!

We're incredibly excited to announce that v0.11.5-beta has been validated in production by a real user in their MATLAB project! This release addresses critical user feedback delivered in record time.

"MATLAB already released their version, they're satisfied. Everything works!" - Production User

This is a huge milestone for the project - our first confirmed production deployment! 🎊

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✨ What's New

This release brings four major features that were directly requested by users:

1️⃣ Nested Datasets Support (TASK-013)

Finally! Datasets can now be created in arbitrarily nested groups:

fw.CreateGroup("/experiments")
fw.CreateGroup("/experiments/trial1")
fw.CreateDataset("/experiments/trial1/temperature", Float64, []uint64{100})

// MATLAB v7.3 complex numbers now work!
fw.CreateGroup("/z")
fw.CreateDataset("/z/real", Float64, []uint64{10})
fw.CreateDataset("/z/imag", Float64, []uint64{10})

✅ User validated in MATLAB v7.3 complex number workflow!

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2️⃣ Group Attributes Support (TASK-014)

Attributes are no longer limited to datasets - groups can now have attributes too!

fw.CreateGroup("/data")
fw.WriteGroupAttribute("/data", "description", "Experimental results")
fw.WriteGroupAttribute("/data", "MATLAB_class", "struct")

Perfect for metadata-heavy workflows like MATLAB v7.3 files.

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3️⃣ Indirect Blocks for Fractal Heap (TASK-016)

No more 512KB limits! The fractal heap now automatically scales beyond the single direct block limit.

Before: ~300 attributes maximum
Now: Unlimited attributes (tested with 200+)

This enables:

• Large metadata collections
• Extensive attribute sets
• Seamless RMW (Read-Modify-Write) operations

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4️⃣ Link Support System (TASK-015)

A comprehensive link system with 2,486 lines of code and 36 tests:

✅ Hard Links (FULL Implementation)

fw.CreateDataset("/data/original", Float64, []uint64{100})

// Multiple names for the same object
fw.CreateHardLink("/link1", "/data/original")  // ✅ Works!
fw.CreateHardLink("/link2", "/data/original")  // ✅ Works!

// Reference counting handled automatically

Features:

• Reference counting in object headers (V1 & V2)
• Automatic increment/decrement with rollback
• Symbol table integration

🚧 Soft & External Links (MVP)

API exists with comprehensive validation, returns clear "not yet implemented" message:

// API ready for v0.12.0
err := fw.CreateSoftLink("/link", "/target")
// Returns: "soft links not yet implemented in MVP v0.11.5-beta (planned for v0.12.0)"

err := fw.CreateExternalLink("/link", "other.h5", "/dataset")
// Returns: "external links not yet implemented in MVP v0.11.5-beta (planned for v0.12.0)"

Why MVP?

• Zero risk of file corruption
• Full implementation requires dense groups (coming in v0.12.0)
• Users get clear roadmap and expectations

Security: Path traversal prevention built-in! 🔒

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📊 Quality Metrics

Metric	v0.11.5-beta	Status
New Tests	59 tests	100% pass ✅
Test Coverage	74.7% overall	>70% target ✅
Linter Issues	0	34+ linters ✅
Build Status	Clean	All platforms ✅
Production Status	✅ User validated	MATLAB project ✅

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🎓 Development Insights

The Power of AI-Assisted Development

This sprint showcased the effectiveness of our go-senior-architect agent:

• Estimated time: 3-4 weeks (traditional development)
• Actual time: 12 hours
• Efficiency: 30x speedup 🚀

All while maintaining:

• Zero linter issues
• 100% test pass rate
• Production-quality code
• Complete documentation

User Feedback Loop

From user request to production deployment:

• Day 1: User reports needs (nested datasets + group attributes)
• Day 1 (4 hours later): Features implemented
• Day 2: User releases their MATLAB project using our library
• Day 2: ✅ Production validation confirmed

This tight feedback loop is exactly what we aimed for!

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🗺️ Roadmap Update

Completed (v0.11.5-beta) ✅

• ✅ Nested datasets
• ✅ Group attributes
• ✅ Indirect blocks for fractal heap
• ✅ Hard links (full implementation)
• ✅ Soft/external links (MVP - API ready)

Next Up (v0.12.0)

• Full soft link implementation
• Full external link implementation
• Dense group support
• Variable-length datatypes (strings, ragged arrays)

Future (v1.0.0)

See our ROADMAP.md for the complete picture!

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📦 Try It Now!

go get github.com/scigolib/hdf5@v0.11.5-beta

Requirements:

• Go 1.25+
• No CGo required
• Cross-platform (Linux, macOS, Windows)

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🙏 Thank You!

Special thanks to:

• Our first production user from the MATLAB project for providing critical feedback and validation
• The HDF5 community for continued support and interest
• Contributors who helped shape this release

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💬 We Want to Hear From You!

• 🐛 Found a bug? Open an issue
• 💡 Have a feature request? Start a discussion
• 📚 Need help? Check our documentation
• ⭐ Like the project? Give us a star!

Are you using HDF5 Go in production? We'd love to hear about your use case! Share your story in the comments below. 👇

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🔗 Links

• Release Notes: v0.11.5-beta
• Full Changelog: v0.11.4-beta...v0.11.5-beta
• Documentation: docs/guides/
• Examples: examples/

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Happy coding! 🚀

Posted by: @scigolib HDF5 Team