JOURNAL
What changed, why it changed, and what we learned in the field.
56 notes shown
Why the 48-Hour Surf Window Matters More Than a 10-Day Chart
Long-range charts are useful for watching storms. The real North Sea surf decision usually happens inside the next 48 hours.
Read noteWhy Swell Arrival Windows Beat Exact Times
A North Sea swell forecast that gives you a narrow arrival window is more honest than one pretending to know the exact minute waves will turn on.
Read noteWhy ML Training Contracts Matter for Surf Forecasts
A surf model is only useful if training rows reflect what the app would have known at forecast time. Otherwise the model learns from the future.
Read noteWhy Map Transparency Matters for Lake Tiles
Transparent no-data areas are not cosmetic. They prevent bathymetry overlays from pretending coverage exists outside mapped water.
Read noteWhy CEFAS, SMHI, and RWS Buoys All Matter
One observation network cannot explain the whole North Sea. Regional buoy sources fill different parts of the forecast picture.
Read noteWhat Offshore Buoys Miss Nearshore
Offshore buoy observations are essential, but they cannot see the tide, wind angle, and nearshore bathymetry that shape your actual session.
Read noteWeather Routing Is Not a Straight Line
For small boats, the fastest route is rarely the geometric shortest line. Wind, current, depth, and timing turn route planning into a moving problem.
Read noteVisibility, Current, and Swell Decide the Dive Window
A dive site can be good on paper and wrong in the water. The useful window appears when visibility, current, swell, and entry risk line up.
Read noteUnder-Keel Clearance Is More Than a Depth Number
A charted depth number does not tell the whole story. Tide, draft, waves, heel, squat, and survey margin all decide how much water a boat really has.
Read noteTurbidity Changes How Fish Hunt
Water clarity is not just an angler comfort metric. It changes predator vision, prey behavior, and the usefulness of different tactics.
Read noteTide Tables Do Not Explain Sandbar Surf
Knowing high and low tide is useful. Knowing how a specific sandbar reacts to that tide is the forecast problem.
Read noteTidal Gates for Small-Boat Routing
A tidal gate is a time constraint. A safe route can become slow, uncomfortable, or unavailable when wind, current, and depth line up badly.
Read noteSpecies Queues Before Runtime Species
The safe way to expand a fishing app is to research species in a queue before promoting them into runtime forecasts.
Read noteSolunar Is a Modifier, Not a Magic Clock
Moon and solunar windows can be useful context, but they should never overpower temperature, oxygen, clarity, tide, and species behavior.
Read noteRoute Planning Needs Current Vectors
A current is speed plus direction. Treating it as a scalar loses the part that decides whether it helps, hurts, or pushes you sideways.
Read noteRead the Break, Not Just the Buoy
A buoy can tell you what happened offshore. A useful North Sea forecast has to translate that signal into what will happen at the beach.
Read notePhysics-Aware ML Without the AI Theater
The useful part of ML in surf forecasting is not hype. It is correcting physical estimates while staying inside what the ocean can plausibly do.
Read noteOxygen, Thermocline, and Why Fish Ignore Perfect Depths
A depth can look perfect on the map and still be wrong for fish if temperature layers and oxygen make that water unusable.
Read noteNorwegian Platforms and Earlier Storm Warnings
Far-north platform observations can give North Sea forecasts earlier hints that wave energy is entering the basin.
Read noteMediterranean Species Expansion Without Making Things Up
Adding Mediterranean fish to Gilli is not just a content task. Taxonomy, depth, temperature, seasonality, and scoring traits need verification before runtime use.
Read noteMeasured Oxygen Beats Oxygen Proxies
Estimated oxygen is useful when nothing else exists. Measured dissolved oxygen should carry more authority in fish activity forecasts.
Read noteA Marine Life Encyclopedia Without False Certainty
Marine life context can help divers plan and learn, but it should avoid pretending to identify, track, or legalize wildlife decisions in the field.
Read noteLive GPS Depth Is the Next Lake Map Step
The same point-depth endpoint that powers tap-to-depth can later answer the boat-position question: how deep is the mapped water under me right now?
Read noteThe Lake Registry Is Product Infrastructure
A mapped lake needs more than a name. Bounds, version, tile templates, depth availability, metadata, and max depth all belong in the registry.
Read noteLake Depth at Your Actual Boat Position
Mapped lake bathymetry should not show one max-depth number everywhere. Gilli is moving toward point-depth queries that answer the exact place you tap or sit.
Read noteImmutable Lake Map Packages Make Safer Rollouts
A published lake should ship as one versioned package: tiles, metadata, depth surface, QA report, provenance, and rollout contract.
Read noteIce Fishing Models Need Extra Humility
Under ice, light, oxygen, snow cover, lake type, and species priors interact in ways that deserve conservative forecast language.
Read noteHow to Read a Wind Diagram for North Sea Surfing
Wind direction, wind speed, and the angle of the coast decide whether a North Sea wave is rideable. Here is how to read a surf wind diagram without guessing.
Read noteFrom Lake Request to Published Map
A lake request should move through a reproducible mapping pipeline: ingest, preprocess, georeference, tile, QA, publish, then app integration.
Read noteFreshwater and Marine Fish Do Not Share One Model
A pike in a stratified lake and a seabass in a tidal sea do not respond to the same signals in the same way.
Read noteWhat Changed After Auditing Fish Activity Models
A useful fishing forecast has to survive scientific pressure. Gilli's scoring work now treats oxygen, temperature, light, clarity, and weak proxies more carefully.
Read noteDogger Bank Is the Hidden Swell Filter
The North Sea is not an empty basin. Shallow features like Dogger Bank can filter, bend, and weaken wave energy before it reaches the beach.
Read noteDiveability Is a Briefing, Not a Score
For divers and freedivers, a single score hides too much. Visibility, current, swell, entry risk, temperature, and timing need to be read together.
Read noteContour-Respecting Lake Maps Are a Different Kind of Bathymetry
A good lake map should preserve the logic of the source contours, not smear a basin into a decorative gradient.
Read noteConfidence-Aware Surf Forecasting Is More Useful Than a Bigger Score
A surf score without confidence hides the most important question: how much should you trust this call today?
Read noteCircuit Breakers for Marine Data
When an upstream marine provider is failing, the forecast should fail fast, preserve the rest of the response, and avoid cascading delays.
Read noteCache Policy for Fishing Data
Weather, tides, bathymetry, species forecasts, and water quality should not share one cache lifetime.
Read noteBathymetry Tiles Are Not Depth Queries
A beautiful contour tile and a point-depth answer are different products. Gilli needs both: visual structure for scanning and queryable depth for decisions.
Read noteBarometric Pressure Is a Weak Fishing Signal
Anglers talk about pressure constantly. The science suggests Gilli should treat it as a bounded, low-confidence signal, not a dominant feeding trigger.
Read noteBackend Hardening Is a Surf Forecast Feature
A forecast is only as useful as the data path behind it. Timeouts, validation, caching, and provider fallbacks are product work, not invisible plumbing.
Read noteWhy AEGIR Needs a Source Registry
Dive briefings need to know which provider informed each signal, how fresh it is, what region it covers, and whether it can be cached offline.
Read noteWhat 'On-Device' Actually Means for a Cycle App
Cycle apps like to say 'on-device' and 'private by design'. The phrase has become marketing. Here is the technical definition we hold ourselves to with Freyja, and the questions you should ask any health app that uses the same words.
Read noteThe Tide Is Not the Bite Window
'Fish the moving water' is the most repeated tip in shore fishing, and it is incomplete. Tide is one input among several. Bait, light, temperature, and pressure decide whether the moving water is the moving water that matters.
Read noteNorth Sea Water Temperature by Month for Surfers
A month-by-month read of North Sea water temperature on the southern coast — Belgium, the Netherlands, and the German Bight — with realistic wetsuit guidance for surfers and a note on what those numbers do to your session length.
Read noteWhy Your Hydration Goal Shouldn't Move With Your Cycle
A growing number of cycle apps adjust your daily water target by phase. The evidence does not support that adjustment. Here is what the literature actually says, what cycle phase does change, and why Freyja keeps the number steady.
Read noteFreyja 2.0.5 Makes Mood Check-Ins Less Blank
Freyja 2.0.5 adds preset feelings to mood check-ins, keeps Today focused on one useful read, improves over-goal hydration progress, and tightens companion answers around your actual data.
Read noteGilli 2.0.1 Reads the Water, Not Just the Weather
Gilli 2.0.1 is live with Lake Ecology, Sea Ecology, live water-column modelling, and mapped bathymetry for three Göteborg-region lakes.
Read noteWhy Your Fishing App Doesn't Know When Fish Actually Bite
Your app says 'great fishing today' every day. That should tell you something. Most fishing predictions use weather and moon phase. That's not how fish biology works.
Read noteWhy We Build Apps for People Who Go Outside
We don't want you staring at your phone. We want you to check it, trust it, and get back to the water. Six apps, one philosophy: outdoor intelligence that respects your time.
Read noteWe Digitised 70 Years of Lake Maps So You Don't Have to Guess Where the Deep Holes Are
Somewhere in a Swedish archive, there's a hand-drawn depth map of your favourite lake. Someone measured it decades ago with a weighted rope and a pencil. We found it, digitised it, and put it on your phone.
Read noteWe Check 20+ Data Sources So You Don't Have To
Behind every Gilli prediction, there's a conversation happening between 20+ scientific data sources. Satellite ocean data, tide tables, atmospheric pressure, water temperature, lunar cycles. You just see the answer.
Read noteThe North Sea Doesn't Care About Your Surf Forecast
Surfline says 1ft. You paddle out to head-high sets. Sound familiar? Global surf models weren't built for the southern North Sea. NORDR was.
Read noteThe Fishing Prediction That Tells You NOT to Go
Every fishing app wants you to go fishing today. Even when you shouldn't. Gilli is the app that respects your time enough to say: stay home, the conditions are bad. Try tomorrow.
Read noteShould You Get in the Water Today?
You drove an hour to the coast. The water looks okay. Is it? Aegir answers the one question every diver and spearfisher asks before suiting up -- and it's honest when the answer is no.
Read noteOne App for Your Whole Body, Zero Data in the Cloud
Your cycle tracker knows more about you than your doctor. Who else has access? Freyja tracks hydration, cycle, mood, and UV exposure -- and none of it ever leaves your phone.
Read noteDesigned for a Boat, Not a Desk
Try reading a pastel gradient chart at noon on a boat. We'll wait. Most apps are designed for offices. Ours are designed for the field -- glare, wet fingers, bouncing deck and all.
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