Why Dossi

Your pump automates the insulin.
You still do everything else.

If you use an automated pump, you already know it doesn't run itself. You're still counting carbs at dinner, still tweaking your settings when something feels off, still cleaning up the highs and lows it didn't catch. Dossi was built to take that work off you.

Today's automated pumps are genuinely good. They adjust your basal, catch some highs, and keep you a lot safer than the manual days. But they still hand a surprising amount back to you. You set the insulin sensitivity and the carb ratios — and re-set them whenever something drifts. You count the carbs at every meal. And because a reactive system has to aim high to stay safe, you're often the one living with numbers that come back higher than you'd like.

The harder part is that the things you do by hand are the things these systems trust most. Tell your pump you ate 60 grams of carbs and it believes you — even though that number was a guess. Your settings stay fixed whether you slept eight hours or four. The automation is real, but it's stacked on top of inputs you're expected to get right every single time.

The goal was simple: move the work off the person and into the app — and make the app forgiving when the numbers it's handed are wrong.

Dossi was started by someone who lives with Type 1 and was tired of being the one holding it all together. It's part of the same do-it-yourself community as Loop and Trio — not a competitor to them, but family. It just makes a different bet about where the work should live: in the app, not in you.

The reasons, one by one

What Dossi does differently

Six things that come up with even the best automated pumps — and how Dossi handles each one.

01
The frustration
The tuning never ends
Every system asks you to set insulin sensitivity, carb ratios, and basal schedules by hand — then re-tune them whenever something drifts. Dossi learns your sensitivity and carb ratio from your own outcomes and updates daily. You're not asked to pick the numbers; the app converges on them for you.
How this works
Dossi starts from the settings you enter, then watches what your glucose actually did after each correction and meal. Once it has enough clean examples, it nudges your insulin sensitivity and carb ratio toward what the data shows — re-checked daily and capped so a few odd days can't swing it far. Full detail in the docs
02
The frustration
Bad inputs poison the learning
Carb counts are always guesses, but a pump treats the number you enter as fact. Dossi tracks how confident each estimate is and gates what it's willing to learn from an uncertain meal — so a rough carb number can't silently retrain your ratios. Even if you set a baseline wrong, it drifts back toward where it should be.
How this works
Every meal estimate carries a confidence level. Dossi will still dose from an uncertain estimate, but it refuses to learn from one — so a rough carb guess can shift a single meal's bolus without quietly retraining your long-term ratios. It only learns from clean, confident data. Full detail in the docs
03
The frustration
Phantom lows, then rebound highs
A pump predicts a low that never comes, cuts insulin, and leaves you high an hour later — then over-corrects into the next swing. Dossi runs a second prediction channel modeled on your body's own counter-regulation, so it stops suspending for lows that aren't real and breaks that overnight up-and-down cycle.
How this works
Alongside its normal forecast, Dossi runs a second model of your body's own glucose production. When you're above target with insulin on board, that model offsets the drop a simple forecast over-predicts — so the loop stops cutting insulin for lows that were never going to happen. It switches off at or below target, so a real low is never hidden. Full detail in the docs
04
The frustration
"In range" isn't the same as "where you want it"
To stay safe, a reactive pump aims high — so you settle higher than you might want. Dossi optimizes the whole predicted glucose curve toward a single target, with lows weighted far more heavily than highs. It can safely aim tighter than a reactive system — if that's what you and your care team want.
How this works
Instead of reacting one reading at a time, Dossi simulates your glucose hours ahead and picks the basal that steers the whole predicted curve to a single target — weighting lows far more heavily than highs. That lets it settle closer to target instead of parking high just to stay safe. Full detail in the docs
05
The frustration
Carb counting is a chore
Typing a carb number at every meal — one you're half-guessing anyway — gets old fast. Snap a photo and Dossi estimates carbs, protein, and fat, then lets you refine it in plain language. You can always enter carbs by hand; it never gates anything safety-critical.
How this works
Photograph the meal and Dossi's vision model estimates carbs, protein, and fat, breaking a compound dish into its parts and looking each up. You can correct it in plain language or just type the number yourself — it's a convenience, never a gate, and you bring your own API key. Full detail in the docs
06
The frustration
Your body isn't the same every day
Sensitivity after a bad night's sleep, after a run, or at 6am isn't the same as midday — but fixed settings pretend it is. Dossi learns your patterns: exercise sensitivity by activity and intensity, dawn phenomenon, sleep, infusion-site age. And it models how fat and protein stretch a meal's absorption, instead of using one flat curve.
How this works
Dossi learns context-specific patterns — exercise by type and intensity, the dawn phenomenon hour by hour, sleep quality, infusion-site age — and only applies one once it's confident. Its meal model also stretches absorption for higher-fat and higher-protein meals instead of assuming one fixed curve. Full detail in the docs

To be clear: different doesn't mean better. Loop, Trio, and today's commercial pumps are proven and have kept a lot of people safe for years. Dossi is one option in a healthy family of tools, and it's not FDA cleared: you build it, install it, and run it yourself, at your own risk. Talk to your care team before changing anything about your therapy. Read the deeper, technical version of this story →

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Dossi is open-source, do-it-yourself software for adults with Type 1 diabetes. It is not a medical device and is not FDA cleared. It does not replace your endocrinologist or your own judgment.