The Simplicity 8379 tank dress is a fast and easy sewing project.

Boy, it’s been a minute since I sewed a Big 4 pattern! I bought Simplicity 8379 in summer 2017 during one of Jo-Ann’s infamous 99-cent pattern sale.

The voluminous side draping (aka, the manta ray “wings”) and minimal pattern pieces (dress, neck binding, and armhole binding) intrigued me, so I thought, “What the heck. Get over here, Simplicity 8379. Let’s dance!”

Simplicity 8379 features voluminous side seams that pool near the hipline.

Fabric for Simplicity 8379

If you’re an astute Sie Macht reader, you may have noticed the purple fabric in this Simplicity 8379 frock is what I used to sew my Me-Made Leggings. I had a bunch of it left over, and this wacky dress seemed like a great application.

The thing is, though, once I laid out the monster-sized dress pattern piece, it was clear I didn’t have enough purple stuff for both front and back of the dress. Drat.

I went back to Jo-Ann, confident I could find more of the purple; here’s the performance fabric in a different colorway. It’s part of the Loungeletics line, and I never had trouble finding these fabrics when cruising the aisles of Jo-Ann.

Except this time, when I needed a specific color, it was no where to be found. I huddled up with a Jo-Ann staffer, and the inventory showed ZERO yards of purple in every store in Wisconsin.

And I was so confident I could bust into Jo-Ann and walk out in 15 minutes later will my purple yardage. I even relayed this prediction to my husband — “Yeah, this is an in-and-out job, for sure.”

I went back to the performance knit zone and looked for another option. I went with same Loungeletics fabric in pink space dye, all the better to live out my Jem and the Holograms fantasies.

Neckline detail of Simplicity 8379.

What’s Great About the Dress


I am so, so, so glad I couldn’t find the purple fabric at Jo-Ann. I LOVE how this dress is reversible front to back, and I LOVE how, because of the drape, you get glimpses of the back fabric from the front. File this dress under “Happy Accidents.”

Wicking Fabric

This is performance fabric, which wicks moisture away from the body. This is a cool dress to wear on a hot day.

Covers Bra

It’s often hard to find sleeveless/tank garments that fully cover an everyday bra. There are no majorly peeking straps with Simplicity 8379.

Choose a drapey fabric when sewing Simplicity 8379.

What Could Have Gone Better

This is a short dress. A very short dress.

I measured its length against this shift dress and decided to add two inches to the hem. I wanted to be able to raise my arms in Simplicity 8379 with indecent exposure.

When I tried on the dress with the added length, however, it wasn’t working. The side volume plus those two inches of length made for something mega-awkward. It looked like the dress swallowed me.

The two inches had to go. I laid the dress on a cutting mat and lopped the additional length with a rotary cutter.

I hemmed the dress on my serger, using a blind hem foot and two-thread narrow flatlock stitch. I love the look of a serged blind hem; from the right side, you see a line of tiny, vertical stitches, on on the wrong side, the raw edge is overlocked.

There is a bit of a learning curve with the blind hem serger foot, and I’m still at the steep part. My hem is less-than even, and the stitches don’t *exactly* connect at the side seam. Oops. I should have basted or something. I’ll give myself a better opportunity for precision next time.

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Simplicity 8379: Hey, why not give this pattern a go?

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Fiskars 45mm Rotary Cutter: I don’t know where I’d be as a sewist without my Fiskars rotary cutters.

OLFA 24″ x 36″ Double-Sided, Self-Healing Rotary Mat: I also have deep feelings about my giant Olfa cutting mat.

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Back view of Simplicity 8379.

Who Should Sew Simplicity 8379

Those Hungry for a Fast Sew

Sometimes, you want to tear through a simple sewing project in a couple of hours (or less). This is your project, peeps. Repeat after me: Three paper pattern pieces.


This is a great project for sewists new to knits. You gain experience working with knits without fitting worries. For this reason, this is an ideal first project if you’re new to serging.

Those Not Interested in Fitting or Tracing

I’m big on muslins, and I almost always trace my patterns. But with Simplicity 8379, I measured the flat pattern piece to choose a size (I sewed an XS) and cut it out. And then I cut out my fashion fabric without making muslin! Gasp! Look, if you know the shoulders are going to fit, there’s no reason you can’t start sewing this style of dress right away.

I made this Simplicity 8379 dress reversible for double the looks.

Traveling Sewists

Make a few of these dresses in fluid poly knits and you’ve got a winning, wrinkle-free travel wardrobe, especially if the front and back are two different colors. If you made three of these dresses and did different colors for the front and back, that’s six different looks! Reversible dresses FTW.

Party People

Simplicity 8379 is an ideal party dress, because:

1.) It’s fast to sew. If you have an event and you’ve got an itch to wear something new… BAM.

2.) It’s going to be different from most of the other dresses there, and everyone likes to wear something original. The draped detail is unusual not something you see in a lot of RTW. (Please correct me if I’m off on this; I only have my perspective to work with. Maybe this look is big in other parts of the world!)

3.) Your tummy has all the room in the world for food and drink!

4.) When the dance floor calls, you can answer with fluid, unencumbered moves.

And speaking of party dresses, wouldn’t this dress be fabulous in stretch velvet? I just solved your holiday sewing plans! Woot!

Those Who Love Hacking Sewing Patterns

I hadn’t thought of hacking this pattern until I came across two posts from the Someday Sewing blog. This dress is SUPER cute with short sleeves and a straight neckline and three-quarter sleeves. I’m definitely trying out one (or both) of those hacks for when the weather cools off; they’d look mighty chic with leggings!

I also think this dress could be eye-catching in a midi-length (think something like this or this). Or maybe experiment with asymmetry (this or this serve major inspo).

Heck, if you were feeling saucy, I bet this dress could be cool in a drapey woven (double gauze, rayon, etc.). I suggest sizing up and adding a zipper; I think getting into those armholes could be tricky. Muslin first!

Other hack ideas include:

  • Adding breast pockets
  • Changing the neckline on one side (e.g., scoop and V-neck)
  • Adding inseam pockets
  • Adding seams for visual interest and colorblocking opportunities

Here's why I call Simplicity 8379 my manta ray dress.

Fans of Manta Rays


Over to you, darlings: Have you sewn a pattern where the front and back pattern pieces were identical? How did it turn out? How would you hack this pattern? Which color do you like better for the front: purple or pink? And what are your feelings on manta rays? Please sound off in comments!

P.S. Here’s the previous post, ICYMI: How to Read La Maison Victor Sewing Magazine.

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